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    Part II: Marine and Freshwater Zoology

    Encyclopedia Arctica 3: Zoology (Excluding Birds)


    Part II: Marine and Freshwater Zoology

    Marine

    Faunistic Effects of Climatic Change in the North


    Unpaginated      |      Vol_III-0468                                                                                                                  
    EA-Zoology

    ( Max M. J. Dunbar)


    FAUNISTIC EFFECTS OF CLIMATIC CHANGE IN THE NORTH

           

    CONTENTS

    Page
    Introduction 1
    Fauna of the Land 6
    Marine Fauna 10
    Bibliography 17



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    EA-Zoology

    (Max J. Dunbar)


           

    FAUNISTIC EFFECTS OF CLIMATIC CHANGE IN THE NORTH

           

    Introduction

            During the past thirty or more years there have been changes in the

    climate of the arctic and subarctic regions, manifested in a progressive

    warming in both the atmosphere and the hydrosphere. Clearly the atmos–

    pheric and marine climates are interrelated, but the mechanism of the

    relation, and the causal paths involved, are at present uncertain. These

    effects have altered the distribution of plants and animals, resulting in

    a general northward extension of distribution, which is much more immediately

    apparent in the sea than in terrestrial environments.

            The whole matter of recent climatic change has been reviewed by

    Ahlmann (2) in a paper in which the climatological, glaciological, oceano–

    graphic, and biological evidence for the recent warming is brought together,

    and some years previous to Ahlmann’s paper, Jensen (15) made an extensive

    review of the pattern of change, particularly as it affected West Greenland.

    Both papers contain extensive bibliographic lists to which the reader is

    referred. The increase in atmospheric temperatures has affected the whole

    of the Northern Hemisphere, in all probability, but information from certain

    parts of the North is lacking. Ahlmann has emphasized the urgency of the need

    for the study of this change in greater detail, and has brought home the fact

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    that “here is something happening” which affects all of us, both at present

    and in the immediate future.

            The underlying cause of the present warming effect, and indeed of longer–

    term variations and fluctuations in climate, is not certain, but as early as

    1916, Helland-Hansen and Nansen suggested that the terrestrial climatic

    variations must ultimately becaused by variations in solar radiation; that

    increased solar radiation set up increased atmospheric movement, and thus the

    faster transmission of energy from the tropics to the poles. That climatic

    variation is normal is obvious from a consideration of the geologic past of

    the earth, and Ahlmann (2) has summarized the effects of recent (post glacial)

    variations in northwest Europe, Iceland, and Greenland, areas in which it is

    clear that the human economy within historic times has been greatly dependent

    upon climatic conditions.

            In the atmospheric climate, the most spectacular changes in recent

    decades have perhaps taken place in Spitsbergen, where there has been an

    increase of no less than 9°C. in the mean winter temperature between the

    period 1911-15 and 1931-35, the actual figures being −17.6°C. for the earlier

    period and −8.6°C. for the later. In Greenland, the winter temperatures at

    Jakobshavn during the period 1923-32 were more than 5°C. warmer than those

    registered fifty years before, and there has been a steady rise since 1932.

    Positive deviations from the former mean temperature, of from 2 to 4 degrees,

    are the rule at all Greenland stations. In Canada, information on atmospheric

    temperatures has recently been brought together by Hare (1950) in an exhaustive

    study of the climate of the Canadian eastern Arctic and Subarctic. At Moose

    Factory, Southwest Point (Anticosti Island), and St. John’s, Newfoundland,

    the coldest period is shown to have been about the year 1915, since which

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    time there has been a slight rise of one or two degrees Fahrenheit in both

    winters and summers. It was warmer in 1870-1910 than between 1915-20.

    Such information as is available from northern stations in the eastern

    arctic of Canada (Craig Harbour, Pond Inlet) also shown an increasing

    temperature. The warming effect is, however, not so marked in Canada as in

    Greenland and (especially) Spitsbergen; in fact, the effect is to some extent

    related to the maritime nature of the climate. In the U.S.S.R., (Rubenstein,

    quoted from Ahlmann 1949) (2), “it appears that an increase in winter tempera–

    tures began about the latter part of the nineteenth century, and that it was

    especially marked at such northern stations as Kola, Archangel and Leningrad,

    while no increase was noticeable, for example, at Kiev.”

            Glaciers all over the world are now receding, for example, a with

    perhaps a few exceptions, and at varying rates. Recession appears to be

    slow in Greenland, but in southern Alaska, Iceland, and Norway the decrease

    in glacier size is impressive.

            The pattern is similar in the marine climate, that is to say in the

    temperature of sea water, at least in the North Atlantic and associated seas.

    In the North Pacific arctic and subarctic area, the picture is uncertain due

    to the lack of extended records with which to compare present observations,

    but there is evidence of an increase in temperatures off the southern

    California coast in recent decades (14), and in the coastal waters of British

    Columbia (26). The marine change is perhaps most marked in West Greenland,

    where the water has been growing warmer since about 1917, apparently owing to

    a strengthening of the Irminger Current component in the West Greenland

    Current (Jensen 1939, Kiilerich 1943, Dunbar 1946 and 1951). The Gulf

    Stream itself has increased in temperature about half a degree centigrade,

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    at its origin in the Straits of Florida. The southern limit of ice in

    the Greenland Sea (east of Greenland) retreated some 200 to 300 kilometers

    between the years 1928 and 1936, and the thickness of the ice in the Polar

    Sea decreased “from an average of 365 cm. during the Hansen Fram expedition

    of 1893-96 to 218 cm. during the drift of the Russian ice-breaker Sedov in

    1937-40” (2). In the Norwegian Sea, there appears to have been an increase

    in both the volume and the temperature of the Atlantic water flowing northward,

    of 2°C., compared with conditions at the beginning of the present century, and

    Ahlmann (2) quotes Russian work on routine hydrographic sections along the

    Kola meridian (33 1/2°E.), which showed an increase of the order of 2°C. in

    the temperature at 200 meters between 1900 and 1921; the earming has been

    continuing since 1921. A rise in temperature of the same extent has been

    demonstrated in Spitsbergen waters, and the shipping season in West Spitsbergen

    has been more than doubled since 1900. It appears, also, that the ice condition [ ?]

    along the Siberian shelf have been easing during the past decades.

            In the Canadian eastern arctic, there is a lack of past records. It is

    reasonable to suppose that the waters off southeast Baffin Island, in Hudson

    Strait, and along the Labrador, have been influenced by the warming of the

    West Greenland Current, most of which turns westward, south of the submarine

    ridge between Greenland and Baffin Island, and takes part in the formation

    of the Labrador Current. There is evidence of a biological nature (see below)

    for the invasion of Atlantic water into Hudson Strait. The only physical

    evidence is in the comparison between temperature and salinity measurements

    made in Hudson Bay and Strait in 1930, by the Fisheries Expedition, and those

    made in 1948 by the H.M.C.S. Haida. Working on these data, Bailey and Hachey

    (5), and Dunbar (6) have shown that there must have been a significant increase

    in both parameters between the years mentioned, which may perhaps be put down

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    to an increased influence of Atlantic water, as in West Greenland.

            There is some evidence also to be gained from comparisons of the

    open-water seasons for shipping in Hudson Strait and Ungava Bay in past

    years and at present. According to all reports and the memory of Older

    residents in the eastern arctic, the possible season for navigation into

    and and out of Ungava Bay, some 20 to 30 years ago, was little more than

    two to two-and-one-half months, or between the beginning of August and some

    time in October. Today the open water season is much longer, extending from

    the middle of July (earlier inside the bay itself) to late November at least,

    probably well into December. Lucien Turner, who visited Fort Chimo in 1882-

    84, records in his 1885 manuscript (27) that his ship was caught in the ice

    at the beginning of August 1882, off the mouth of the George River; this

    could hardly happen during the present years, when all the ice is out of

    Ungava Bay by the middle of July.

            Farther south in Canada, exceptionally high surface temperatures have

    been recorded along the Atlantic coast in 1947 and 1949 (19), phenomena

    which appear to be part of a general pattern of warming.

            In this general process there have of course been relapses. In 1938

    there was a very cold season in West Greenland, and the winter of 1948-49

    was one of the coldest on record. In the Siberian waters, ice conditions

    were bad in 1933, 1934, and 1936 (2), in the Kara Sea, and in 1942 they were

    again bad, worse along the whole northern route than at any time in recent

    years. There are similar variations in the ice conditions in the Canadian

    eastern arctic. It has been suggested by the present writer (8) that there

    has not been any significant increase in water temperatures in West Greenland

    since about 1936, and that it is possible that the present warm period is

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    leveling off. It is much too early yet to form any firm opinion, or to

    attain any sort of certainty on this point. Surface temperatures in Georgia

    Strait, British Columbia, have been falling somewhat since 1940 (26).

           

    Fauna of the Land

            A warning should be sounded at the beginning of this section to the

    effect that ( 1 ) recent northward extensions of distribution in terrestrial

    fauna may not be caused by climatic change at all, at least in the obvious

    and direct sense, and ( 2 ) if there is an important element of climatic

    control, climatic change in the atmosphere may be long in inducing change

    in distribution of animals; there may be a considerable time lag. Terrestrial

    animals are not, for the most part, so delicately adjusted to environmental

    temperature conditions as are aquatic animals.

            The first possibility, that direct climatic control may not be involved,

    follows from the fact that the areas that fall within the terms of reference

    of this encyclopedia have generally been recently freed from a covering of

    ice. Once the ice has retreated, the processes of soil formation will continue,

    albeit at rates controlled by the climate, no matter whether the climate is

    cooler or warmer. As soil formation proceeds, so will colonization by plants

    and by animals. The rate of colonization (which is manifested by northward

    extensions of distribution) will depend on climatic variation, but the mere

    fact of northward extension does not necessarily imply a causal connection

    with present climatic warming.

            The fact that terrestrial animals, and especially the homotherms (birds

    and mammals), are less delicately adjusted to temperature differences than

    are aquatic animals, is demonstrated in an a priori manner by the failure

    of the “life-zone” concept in classifying or formalizing the distribution

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    of life in North America. Founded upon temperature conditions alone,

    Merriam’s original life zones are of only very general value, little more

    than a useful descriptive convention. Nevertheless, it is clear that the

    complex of factors which does control the distribution of animals is at some

    point concerned with the atmospheric temperature aved average. Griscom (11),

    in criticizing the life-zone system as applied to the distribution of birds,

    seems to swing too far in the other direction, and to place too little impor–

    tance upon temperature. He says, for instance: “In my lifetime various birds

    have been steadily pushing northward and northeastward, and it follows, con–

    sequently, that the present isothermal lines of their northernmost limits

    are very much cooler than the isothermal lines that constituted limits

    twenty-five years ago. In other words, it is obvious that temperature has

    not limited the northward distribution of these birds in any way whatsoever.”

    (11) p.160). The reclamation by birds of previously glaciated territory is

    no doubt keeping pace with the reclamation by plants and other organisms,

    but the influence of temperature upon the rate of that reclamation cannot

    be ignored. With this preliminary warning of the limits of our present

    knowledge, examples of recent northward extensions in the distributions of

    organisms can be discussed.

            The effect is of course not restricted to the arctic and subarctic

    regions, but it is with these regions only that we are concerned here.

    Griscom (10; 11) has mentioned several birds which have spread northward

    in the United States recently, and Hubbs (14) has studied the question of

    recent changes in the distribution of marine fish in the pacific coastal

    waters, also of the United States.

            Northward creep of vegetation has been observed in Iceland and in

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    Norway, Sweden, and Finland. “In the forests of northern Scandinavia the

    economic benefits are of special importance. The trees are spreading

    rapidly above their former limits, and the annual rings of both pine and

    spruce show a quicker growth than they have for about two decades… Large,

    formerly bare areas are now being [ ?] invaded principally by birch and

    willow; the timberline of the mountain birch is rising higher and higher.

    Vegetation in general is becoming more luxuriant” (2). A similar creep

    northward of the tree line has been observed in Alaska. A similar studies

    of the tree line in northern Canada do not appear to have been published,

    but the northward movement of certain mammals has been observed.

            Rand (21) describes the coyote ( Canis latrans ) as the best example of

    recent change in status and distribution. The coyote has “within the present

    century…greatly extended its range northward and eastward and now occurs

    as far north as the arctic ocean.” It is now known at Point Barrow, Alaska,

    and in the Mackenzie Delta area. The red fox ( Vulpes fulva ) has been

    gradually extending its range beyond the tree line and well into the edge

    of the barren grounds. It is now recorded from southern Baffin Island (23)

    and from Southampton Island (24). Whether this extension of range is

    strictly referable to the climatic “amelioration” is uncertain; it might

    conceivably be due to increased pressure from human populations farther

    south.

            The moose ( Alces americana ) was described by Anderson (4) as increasing

    rapidly in numbers at that date, and also as extending its range northward,

    in the Mackenzie district. Again in 1924, Anderson recorded similar events

    in the moose population. The moose had formerly, according to Macfarland (20),

    been scarce in this region. Rand (21) doubts whether this increase in numbers

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    and in range of the moose can be ascribed to climatic factors, and is

    inclined instead to suppose that such fluctuations in the moose population

    are due to a combination of other factors, such as parasites, disease, and

    activities of man.

            The activities of man in the cultivation of the land, farther south

    than our present area, have long been known to affect the range of birds

    and mammals. The movement northward of the white-tailed deer ( Odocoileus

    virginianus borealis ) following the cutting of its native coniferous forests,

    is such an example which should be mentioned here (3, p.7). Reduction in the

    northern forests may also be related to the extensions of range in the coyote

    and red fox, already mentioned, and in the apparent gradual colonization of

    the barren lands by the wolverine (Gulo luscus).

            Among birds, there are many examples of northward extension of breeding

    ranges in the temperate parts of the Northern Hemisphere, including Iceland,

    but evidence of such extension in the Arctic seems to be scarce. Indeed, it

    appears as though the crossing of the tree line is a step which requires

    greater stimulation than a mere rise in temperature of one or two degrees.

    It is in fact probable that birds which habitually breed up to the limit of

    trees will not move farther north except as the tree limit does, and the

    latter movement is of course slow. There are occasional records of conifer–

    forest birds from well north of the tree line, such as that of a magpie ( Pica

    pica hudsonia ) (22) from the Dubawnt River area, Northwest Territories, but

    it is very doubtful whether such strays can be accepted as evidence of a true

    extension of normal range.

            Before leaving the subject of the possible effects of recent climatic

    change upon the terrestrial fauna, which effects, as w e i ll be apparent from

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    the somewhat scant evidence available, are not well marked nor with any

    certainty related to the climate, mention should be made of an interesting

    development in Greenland which seems to demonstrate a physiological effect

    of increasing temperatures and general amelioration of climate. Faester (9)

    has shown that the percentage of “summer skins,” or skins with thin fur

    more or less dominated by brownish color, in the commercial take from South

    Greenland has increased since 1929 from between 1.5 and 5% to 21% in 1938.

    This increase is not due to any alternation in the trapping season, nor to

    any change in handling of the skins for the Danish market. It represents

    an actual difference in the state of color change of the white and blue

    fox population during the trapping season, and Faester has related it to

    the milder climate. It is interesting to note that the increase in the

    pop proportion of “summer skins” in the catch occurred not during the

    period following the greatest rise, in the decade of the 1930’s, when the

    mean temperatures began to level off. This suggests that it is not the

    direct effect of temperature that is concerned, but an indirect effect,

    perhaps working through general conditions of nutrition.

           

    Marine Fauna

            The effects of change in the marine climate are clearly more immediate

    than those on land. The whole environment is affected simultaneously, over

    large areas, and there are few microclimates to build up special local

    conditions which obscure the picture as a whole. Marine organisms, as has

    already been pointed out, are for the most part very sensitive to small

    changes in temperature, much more so than terrestrial animals.

            Following immediately upon the hydrographic changes described above,

    brought about mainly by an increase in the heat and transport of the Gulf

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    Stream and North Atlantic Drift, there occurred sweeping changes in the

    fauna of the waters from Siberia westward to Baffin Bay. In the Barents

    Sea, the Atlantic cod ( Gadus callarias ) appeared much farther east in 1921

    than formerly, and continued to spread eastward. Along the Murman Coast,

    this eastward spread was observed in a great variety of animals, including

    the mollusk Cardium edule , and the echinoderm Echinus esculentus . Arctic

    species of fishes, such as Leptagonus decagonus and Gymnacanthus tricuspis ,

    have become scarce in this Murman area, and have been replaced by Atlantic

    species, such as Zeugopterus norvegicus and Chirolophus galerita , and even

    the mackerel ( Scomber scombrus ) and the herring ( Clupea harengus ) have

    become abundant. The herring, mackerel, and coalfish ( Gadus virens ) were

    reported for the first time from the west coast of Novaya Zemlya in 1936,

    by Agapov and Toporkov (1), who write: “The appearance of these fishes,

    aliens to the Arctic, is caused by the same factors as the appearance of

    the cod and some other fishes in the Kara Sea, namely the general warm spell

    of the past few years” (Agapov and Toporkov, quoted from Jensen) (15). The

    Atlantic salmon ( Salmo salar ) was found to have invaded the Kara River in 1932.

            The fisheries of northern Norway have been greatly increased during the

    present warm period, and the important cod fisheries around Bear Island and

    in the waters west and south of Spitsbergen are entirely a product of this

    warming effect. The contrast in the Norwegian fisheries today and those of

    the preceding colder period are well expressed in the following quotation

    from Jensen (15):

            “During the cold period something happened, which was diametrically

    opposite to what occurred in the following warm period. In the years 1902

    and 1903 arctic animals, such as the Greenland Seal ( Phoca groenlandica ),

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    the Ringed Seal ( Phoca foetida ) and the White Whale ( Delphinapterus leucas ),

    whose mass-wanderings are otherwise restricted to purely arctic regions,

    came down in enormous schools to the northern coasts of Norway and farther

    also along the west coast. Previously the fixed ice-boundary had advanced

    farther west and south than any one could remember; even in May 1902 it

    extended as a continuous wall from Spitsbergen and Bear Island down towards

    the Murman coast, not far from Varanger Fjord, presumably owing to the

    prevailing northerly and easterly winds over Spitsbergen and the Barents Sea.

    The temperature of the sea and air was noted as low. The special meteorological

    and hydrographical conditions in conjunction with the advance of the ice were

    taken to be the cause of the mass-incursion of arctic animals to Norway.

    At the same time the great cod fisheries in the northern district of Norway

    were a failure and the fishermen believed that the arrival of the seals had

    driven the cod from the coast. It might be questioned, however, whether it

    was not the changed natural conditions, which enabled the arctic seals and

    whales to thrive on the northern coasts of Norway, which had the opposite

    influence on the boreal cod and forced them to go elsewhere.”

            The history of the Spitsbergen fishery is recorded elsewhere in this

    Encyclopedia . It will be enough here to mention that between its beginning

    in 1874 and the present day, there was a period, from 1883 to 1926, when

    colder conditions returned and the fishery disappeared.

            In the waters around Jan Mayen, Atlantic cod and herring were taken in

    1930 and 1931, but not in commercial quantities. The Michael Sars expedition

    of 1900, under the direction of Johan Hjort, had found no food fishes at

    Jan Mayen.

            Perhaps the most spectacular of all these faunal changes has taken place

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    in the waters of Greenland, especially West Greenland, owing to the increased

    activity and heat content of the Irminger Current, a branch of the North

    Atlantic Drift, which turns north and then west, in the region southwest

    of Iceland, to meet the cold East Greenland Current and, together with the

    latter, taking part in the formation of the West Greenland Current. The

    list of Atlantic animals that have appeared or increased in range in West

    Greenland waters since the beginning of the warm period (about 1917) is

    large, and includes the following:

            Atlantic cod appeared in increasing quantities and farther north each

    year. This process, with the associated development of fisheries in Greenland,

    is described in detail elsewhere (see “Greenland Fisheries”). The cod

    came originally from Iceland, and gradually became established as a breeding

    stock in the fjords and on the banks of West Greenland. In 1929, a haddock

    ( Gadus aeglefinus ) was caught in the Julianehaab district, a species which

    had never before been recorded from Greenland waters. The haddock has not

    become abundant, but other specimens have occasionally been caught since

    1929. In 1936, another first record was made, when the brosme ( Brosmius

    brosme ) was [ ?] taken in the Holsteinsborg district. The ling ( Molva

    vulgaris ) was first caught in 1928, in the Frederikshaab district, and

    the Atlantic halibut ( Hippoglossus vulgaris ), known previously only from

    the banks south of Davis Strait, has invaded the Baffin Bay coast of West

    Greenland, at least as far as the Upernivik district. The herring, pre–

    viously known in small numbers in the extreme southwest of Greenland, has

    increased its range northward at least as far as the Umanak district on

    the west coast, and was first recorded on the east coast in 1932, from the

    Angmagssalik area. It has since been seen in Scoresby Sound. The spiny

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    dogfish ( Squalus acanthias ), formerly rare in Greenland waters, has appeared

    in greater numbers from the south. The rosefish, or Norway haddock ( Sebastes

    marinus ), has become plentiful, and has now been shown to breed in West

    Greenland waters (15).

            Certain fishes, previously common in the waters of the southern part

    of Greenland, have moved northward during the present period of warmer condi–

    tions. This class includes the Greenland or fjord cod ( Cadus ogac ), which

    has become increasingly scarce in South Greenland and more abundant in the

    north; and the capelin ( Mallotus villosus ), which was formerly most abundant

    in the area south of Disko Bay on the west coast and of Angmagssalik on the

    east coast, and has now moved the gravity point of its distribution farther

    north. The capelin is now known from Thule and from Scoresby Sound. Probably

    as a result of this movement in the capelin population population, the harp seal ( Phoca

    groenlandica ) is now common in the northern part of West Greenland than

    in the south.

            One whale, the pilot whale, blackfish, or ca’ing whale ( Globicephala

    ventricosa ), formerly Globiceps melas ), has appeared in West Greenland waters

    in recent years, as far north as Disko Bay.

            These are the most obvious increases in fauna, or in faunal range, in

    Wet Greenland waters. There are also many planktonic animals and plants

    which have invaded the West Greenland Current under the greater Irminger

    Current influence. Jensen (15) mentions the medusa Halopsis ocellata as

    an example, first recorded by Kramp (18) from collections made in 1928.

    Another good example, also a coelenterate, recorded by Kramp is Hybocodon

    prolifer , another Atlantic form first taken in West Greenland by the Godthaab

    expedition in 1928 (17).



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            As would be expected, the invasion of Atlantic forms has been accompanied

    by a retreat of the strictly arctic animals. This is best exemplified by the

    northward retreat, in West Greenland, of the beluga or white whale, and the

    narwhal ( Monodon monoceros ), both of which are now rare south of Disko Bay.

    The Greenland or arctic halibut ( Reinhardtius hippoglossoides ) is another

    arctic-water species that has become much more scarce in southwest Greenland

    since the 1920’s.

            In the Canadian waters of the eastern arctic, faunistic changes are

    much less marked than in West Greenland, in accordance with the lesser degree

    of hydrographic change. Indeed, it is not possible to point to a single in–

    stance of northward extension of range, or of retreat northward, with any

    degree of certainty, partly because of the absence of good past faunal records.

    It is generally reported that the ringed seal ( Phoca hispida = Phoca foetida )

    is now less abundant in Ungava Bay and the region south of Hudson Strait

    than in former decades, but figures are lacking, and moreover if any decrease

    has in fact taken place, it is more than possible that it is due to human

    activity. Decreasing numbers of ringed seal have even been reported by

    residents in southern Baffin Island, but again, if the decrease is true, it

    is not possible to ascribe it to hydrographic change. The same applies to

    the drastic reduction in the distribution range of the Atlantic walrus

    ( Odobenus rosmarus ) in the past hundred years (see “Arctic and Subarctic Seals”).

            The coelenterate Hybododon prolifer , mentioned above as being first

    found in West Greenland in 1928, was taken in large numbers in Lake Harbour

    Inlet, southern Baffin Island, in 1939 and 1940 (7) (see “Marine Plankton”).

    It is impossible to know how long it has been there, but since it was not

    found in the well-worked Greenland waters until 1928, it is very probable

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    that it is a fairly recent arrival in Hudson Strait. It has since been taken

    in numbers in Ungava Bay (unpublished date).

            The capelin, whose distribution has been altered in West Greenland, is

    also of interest in this respect in the Canadian waters. It is most abund–

    dant in the northern waters of Newfoundland, and along the Labrador, particu–

    larly in the southern part. In four seasons of collecting in Ungava Bay, the

    present writer obtained only two specimens of Mallotus , and it is not known

    to the present-day Eskimos of that region. Lucien Turner, however, visiting

    Ungava Bay in the years 1882-84, records in his manuscript report (27) on the

    fishes (never yet published; the auther is here indebted to the Smithsonian

    Institution for the loan of the manuscript) that capelin had not been recorded

    within Hudson Strait until several years previous to 1884 “when a few were

    seen in the neighboring waters of George’s River.” Continuing the quotation

    from the Turner manuscript: “In the spring of 1884 they were observed in

    great numbers in that vicinity [George’s River, or, more properly, George

    River]. On the 8th of August 1884 a school of several thousand individuals

    appeared four miles within the mouth of the Koksoak River. As many as were

    desired for specimens were secured by the hand as they swam near the shore….

    This is the first instance known either to whites or natives of the appearance

    of capelin in the southern portion of Ungava Bay. They are well known to the

    Eskimo, who apply the name Kolelekuk to the caplin” (Turner 1885).

            It is at once clear that faunal conditions in Ungava Bay in 1884 were

    different from conditions in 1950. Capelin are now very rare, and they are

    not known to the natives. They are North Atlantic fishes, edging into the

    Subarctic, and they are seldom seen in swarms in water of temperature below

    6°C. (25), although they have recently been observed in very large numbers

    016a      |      Vol_III-0485                                                                                                                  
    EA-Zoo. Dunbar: Faunistic Effects of Climatic Change

    in 2°C. water in southeastern Newfoundland waters (Templeman, private

    communication). At all events, the presence of capelin in large numbers

    in Ungava in 1884 is a general indication of warmer conditions in the

    water than exist at present. And yet, as has been recorded above, Turner

    met with much more severe ice conditions in 1882 than are known today. It

    is much to be deplored that routine temperature and salinity observations

    were not kept at regular intervals in the eastern arctic of Canada in past

    decades, because it is obvious that the history of hydrography and faunal

    distribution in those waters has been varied, and the evidence brought

    together here shows that the relations between atmospheric and marine

    climate, and marine fauna, may not have been simple.



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    BIBLIOGRAPHY

    1. Agapov, I.D., and Toporkov, G.N. “Some data concerning the fishes

    of Novaya Zemlya.” Problems of the Arctic, vol.2, p.108.

    Leningrad, 1937. (In Russian)

    2. Ahlmann, H. “The present climate fluctuation.” Geogr.Jour ., CXII

    (4-6), pp.165-193, 1949.

    3. Anderson, R.M. “Catalogue of Canadian recent mammals.” Nat.Mus .

    Canada., Bull . No.102, 1946.

    4. ----. “Report on the natural history collections of the expedition,”

    Stefansson’s My Life with the Eskimo , Macmillan, New York,

    1913.

    5. Bailey, W.B., and Hachey, H.B. “An increasing Atlantic influence in

    Hudson Bay.” Joint Committee on Oceanography, St.Lawrence,

    N.B. 11 pp. (mimeographed). 1949.

    6. Dunbar, M.J. “Eastern Arctic Waters.” Fish.Res.Bd. Canada, Bull. No.88,

    1951.

    7. ----. “Marine macroplankton from the Canadian Eastern Arctic. II.

    Medusae, et.” Can.J.Research , D, 20, pp.71-77, 1942.

    8.----. “The state of the West Greenland current up to 1944.” Fish.Res.Bd .,

    Canada, Jour . VI (7), pp.460-471, 1946.

    9. Faester, K. “Effect of the climatic amelioration of the past decade on

    the autumn change of coat of the arctic fox in Greenland.”

    Medd.Grønl . vol.142 (2), 1945.

    10. Griscom, L. The Birds of Concord . Cambridge, Mass., Harvard University

    Press, 1949.

    11. ---. Modern Bird Study . Cambridge Mass., Harvard University Press, 1945.

    12. Hare, F.K. “The climate of the eastern arctic and subarctic of Canada

    and its influence on accessibility.” Report for the Government

    of Canada (Manuscript), 1950.

    13. Helland-Hansen, B., and Nansen, F. “Temperature variations in the North

    Atlantic Ocean and in the atmosphere.” Videnskapselskapets

    Skrifter, I. , Mat.-Naturv. Klasse, 1916 (9).

    14. Hubbs, C.L. “Changes in the fish fauna of western North America correlated

    with changes in ocean temperature.” J.Mar.Res. , VII (3),

    pp.459-480, 1949.



    018      |      Vol_III-0487                                                                                                                  
    EA-Zoo. Dunbar: Faunistic Effects of Climatic Change

    Bibliography

    15. Jensen, Ad. S. “Concerning a change of climate during recent decades

    in the arctic and subarctic…, etc.” Det.Kgl.Danske Vidensk .

    Selsk., Biol Medd. , XIV (8), 1939.

    16. Kiilerich, A.B. “The hydrography of the west Greenland fishing banks.”

    Medd. fra Komm.Danm.Fisk. og Havunders. , Ser Hydrografi, 3 (3),

    1943.

    17. Kramp, P.L. “Medusae (Godthaab Expedition 1928).” Medd.Grøn ., vol.81

    (1), 1942.

    18. ----. “A revision of the Medusae belonging to the Family Mitrocomidae”

    Vidensk. Medd.Dansk Naturh.Foren ., 92, pp.305-384, 1932.

    19. Lauzier, L. “Unusually warm surface sea-water in 1949.” Fish.Res.Bd.

    Canada, Progress Rep . Atlantic Coast Stations, No.51, p.17,

    1950.

    20. MacFarlane, R. “Notes on the mammals collected and observed in the

    northern Mackenzie district, Northwest Territories.” Proc .

    U.S. Nat.Mus., 28, pp.673-764, 1905.

    21. Rand, A.L. “The mammals of northern Canada from a utilization viewpoint.”

    Report for the Government of Canada. (Manuscript). I-XIV,

    pp.1-809, 1949.

    22. ----. “Northern records of the magpie, Pica pica hudsonia (Sabine).”

    Can.Field-Nat ., 59 (1), p.45, 1945.

    23. Soper, J.D. “The mammals of southern Baffin Island, Northwest Territories,

    Canada.” J.Mamm. , 25 (3), pp.221-254, 1944.

    24. Sutton, G.M., and Hamilton, W.J. “The mammals of Southampton Island.”

    Mem. Carn.Mus., 12 (2), 1932.

    25. Templeton, W. “The life history of the Chaplin ( Mallotus villosus O.F.

    Müller) in Newfoundland waters.” Bull . Nfld.Govt.Lab.,

    No.17 (Research), 1948.

    26. Tully, J.P. “Seasonal cycles in the sea.” Fisheries Res.Bd. Canada,

    Progress Rep . Pacific Coast Stations, No.85, pp.88-90, 1950.

    27. Turner, L.M. “Fishes.” (Manuscript report deposited in the Smithsonian

    Institution, Washington, D.C.), 1885.

           

    Max M. J. Dunbar

    Faunistic Effects of Climatic Change in the North (repeated)


    Unpaginated      |      Vol_III-0488                                                                                                                  
    EA-Zoology

    ( Max M. J. Dunbar)


    FAUNISTIC EFFECTS OF CLIMATIC CHANGE IN THE NORTH

           

    CONTENTS

    Page
    Introduction 1
    Fauna of the Land 6
    Marine Fauna 10
    Bibliography 17



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    EA-Zoology

    (Max J. Dunbar)


           

    FAUNISTIC EFFECTS OF CLIMATIC CHANGE IN THE NORTH

           

    Introduction

            During the past thirty or more years there have been changes in the

    climate of the arctic and subarctic regions, manifested in a progressive

    warming in both the atmosphere and the hydrosphere. Clearly the atmos–

    pheric and marine climates are interrelated, but the mechanism of the

    relation, and the causal paths involved, are at present uncertain. These

    effects have altered the distribution of plants and animals, resulting in

    a general northward extension of distribution, which is much more immediately

    apparent in the sea than in terrestrial environments.

            The whole matter of recent climatic change has been reviewed by

    Ahlmann (2) in a paper in which the climatological, glaciological, oceano–

    graphic, and biological evidence for the recent warming is brought together,

    and some years previous to Ahlmann’s paper, Jensen (15) made an extensive

    review of the pattern of change, particularly as it affected West Greenland.

    Both papers contain extensive bibliographic lists to which the reader is

    referred. The increase in atmospheric temperatures has affected the whole

    of the Northern Hemisphere, in all probability, but information from certain

    parts of the North is lacking. Ahlmann has emphasized the urgency of the need

    for the study of this change in greater detail, and has brought home the fact

    002      |      Vol_III-0490                                                                                                                  
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    that “here is something happening” which affects all of us, both at present

    and in the immediate future.

            The underlying cause of the present warming effect, and indeed of longer-

    term variations and fluctuations in climate, is not certain, but as early as

    1916, Helland-Hansen and Nansen suggested that the terrestrial climatic

    variations must ultimately becaused by variations in solar radiation; that

    increased solar radiation set up increased atmospheric movement, and thus the

    faster transmission of energy from the tropics to the poles. That climatic

    variation is normal is obvious from a consideration of the geologic past of

    the earth, and Ahlmann (2) has summarized the effects of recent (post glacial)

    variations in northwest Europe, Iceland, and Greenland, areas in which it is

    clear that the human economy within historic times has been greatly dependent

    upon climatic conditions.

            In the atmospheric climate, the most spectacular changes in recent

    decades have perhaps taken place in Spitsbergen, where there has been an

    increase of no less than 9°C. in the mean winter temperature between the

    period 1911-15 and 1931-35, the actual figures being −17.6°C. for the earlier

    period and −8.6°C. for the later. In Greenland, the winter temperatures at

    Jakobshavn during the period 1923-32 were more than 5°C. warmer than those

    registered fifty years before, and there has been a steady rise since 1932.

    Positive deviations from the former mean temperature, of from 2 to 4 degrees,

    are the rule at all Greenland stations. In Canada, information on atmospheric

    temperatures has recently been brought together by Hare (1950) in an exhaustive

    study of the climate of the Canadian eastern Arctic and Subarctic. At Moose

    Factory, Southwest Point (Anticosti Island), and St. John’s, Newfoundland,

    the coldest period is shown to have been about the year 1915, since which

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    time there has been a slight rise of one or two degrees Fahrenheit in both

    winters and summers. It was warmer in 1870-1910 than between 1915-20.

    Such information as is available from northern stations in the eastern

    arctic of Canada (Craig Harbour, Pond Inlet) also shown an increasing

    temperature. The warming effect is, however, not so marked in Canada as in

    Greenland and (especially) Spitsbergen; in fact, the effect is to some extent

    related to the maritime nature of the climate. In the U.S.S.R., (Rubenstein,

    quoted from Ahlmann 1949) (2), “it appears that an increase in winter tempera–

    tures began about the latter part of the nineteenth century, and that it was

    especially marked at such northern stations as Kola, Archangel and Leningrad,

    while no increase was noticeable, for example, at Kiev.”

            Glaciers all over the world are now receding, for example, a with

    perhaps a few exceptions, and at varying rates. Recession appears to be

    slow in Greenland, but in southern Alaska, Iceland, and Norway the decrease

    in glacier size is impressive.

            The pattern is similar in the marine climate, that is to say in the

    temperature of sea water, at least in the North Atlantic and associated seas.

    In the North Pacific arctic and subarctic area, the picture is uncertain due

    to the lack of extended records with which to compare present observations,

    but there is evidence of an increase in temperatures off the southern

    California coast in recent decades (14), and in the coastal waters of British

    Columbia (26). The marine change is perhaps most marked in West Greenland,

    where the water has been growing warmer since about 1917, apparently owing to

    a strengthening of the Irminger Current component in the West Greenland

    Current (Jensen 1939, Kiilerich 1943, Dunbar 1946 and 1951). The Gulf

    Stream itself has increased in temperature about half a degree centigrade,

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    at its origin in the Straits of Florida. The southern limit of ice in

    the Greenland Sea (east of Greenland) retreated some 200 to 300 kilometers

    between the years 1928 and 1936, and the thickness of the ice in the Polar

    Sea decreased “from an average of 365 cm. during the Hansen Fram expedition

    of 1893-96 to 218 cm. during the drift of the Russian ice-breaker Sedov in

    1937-40” (2). In the Norwegian Sea, there appears to have been an increase

    in both the volume and the temperature of the Atlantic water flowing northward,

    of 2°C., compared with conditions at the beginning of the present century, and

    Ahlmann (2) quotes Russian work on routine hydrographic sections along the

    Kola meridian (33 1/2°E.), which showed an increase of the order of 2°C. in

    the temperature at 200 meters between 1900 and 1921; the earming has been

    continuing since 1921. A rise in temperature of the same extent has been

    demonstrated in Spitsbergen waters, and the shipping season in West Spitsbergen

    has been more than doubled since 1900. It appears, also, that the ice condition [ ?]

    along the Siberian shelf have been easing during the past decades.

            In the Canadian eastern arctic, there is a lack of past records. It is

    reasonable to suppose that the waters off southeast Baffin Island, in Hudson

    Strait, and along the Labrador, have been influenced by the warming of the

    West Greenland Current, most of which turns westward, south of the submarine

    ridge between Greenland and Baffin Island, and takes part in the formation

    of the Labrador Current. There is evidence of a biological nature (see below)

    for the invasion of Atlantic water into Hudson Strait. The only physical

    evidence is in the comparison between temperature and salinity measurements

    made in Hudson Bay and Strait in 1930, by the Fisheries Expedition, and those

    made in 1948 by the H.M.C.S. Haida. Working on these data, Bailey and Hachey

    (5), and Dunbar (6) have shown that there must have been a significant increase

    in both parameters between the years mentioned, which may perhaps be put down

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    to an increased influence of Atlantic water, as in West Greenland.

            There is some evidence also to be gained from comparisons of the

    open-water seasons for shipping in Hudson Strait and Ungava Bay in past

    years and at present. According to all reports and the memory of Older

    residents in the eastern arctic, the possible season for navigation into

    and and out of Ungava Bay, some 20 to 30 years ago, was little more than

    two to two-and-one-half months, or between the beginning of August and some

    time in October. Today the open water season is much longer, extending from

    the middle of July (earlier inside the bay itself) to late November at least,

    probably well into December. Lucien Turner, who visited Fort Chimo in 1882-

    84, records in his 1885 manuscript (27) that his ship was caught in the ice

    at the beginning of August 1882, off the mouth of the George River; this

    could hardly happen during the present years, when all the ice is out of

    Ungava Bay by the middle of July.

            Farther south in Canada, exceptionally high surface temperatures have

    been recorded along the Atlantic coast in 1947 and 1949 (19), phenomena

    which appear to be part of a general pattern of warming.

            In this general process there have of course been relapses. In 1938

    there was a very cold season in West Greenland, and the winter of 1948-49

    was one of the coldest on record. In the Siberian waters, ice conditions

    were bad in 1933, 1934, and 1936 (2), in the Kara Sea, and in 1942 they were

    again bad, worse along the whole northern route than at any time in recent

    years. There are similar variations in the ice conditions in the Canadian

    eastern arctic. It has been suggested by the present writer (8) that there

    has not been any significant increase in water temperatures in West Greenland

    since about 1936, and that it is possible that the present warm period is

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    leveling off. It is much too early yet to form any firm opinion, or to

    attain any sort of certainty on this point. Surface temperatures in Georgia

    Strait, British Columbia, have been falling somewhat since 1940 (26).

           

    Fauna of the Land

            A warning should be sounded at the beginning of this section to the

    effect that ( 1 ) recent northward extensions of distribution in terrestrial

    fauna may not be caused by climatic change at all, at least in the obvious

    and direct sense, and ( 2 ) if there is an important element of climatic

    control, climatic change in the atmosphere may be long in inducing change

    in distribution of animals; there may be a considerable time lag. Terrestrial

    animals are not, for the most part, so delicately adjusted to environmental

    temperature conditions as are aquatic animals.

            The first possibility, that direct climatic control may not be involved,

    follows from the fact that the areas that fall within the terms of reference

    of this encyclopedia have generally been recently freed from a covering of

    ice. Once the ice has retreated, the processes of soil formation will continue,

    albeit at rates controlled by the climate, no matter whether the climate is

    cooler or warmer. As soil formation proceeds, so will colonization by plants

    and by animals. The rate of colonization (which is manifested by northward

    extensions of distribution) will depend on climatic variation, but the mere

    fact of northward extension does not necessarily imply a causal connection

    with present climatic warming.

            The fact that terrestrial animals, and especially the homotherms (birds

    and mammals), are less delicately adjusted to temperature differences than

    are aquatic animals, is demonstrated in an a priori manner by the failure

    of the “life-zone” concept in classifying or formalizing the distribution

    007      |      Vol_III-0495                                                                                                                  
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    of life in North America. Founded upon temperature conditions alone,

    Merriam’s original life zones are of only very general value, little more

    than a useful descriptive convention. Nevertheless, it is clear that the

    complex of factors which does control the distribution of animals is at some

    point concerned with the atmospheric temperature aved average. Griscom (11),

    in criticizing the life-zone system as applied to the distribution of birds,

    seems to swing too far in the other direction, and to place too little impor–

    tance upon temperature. He says, for instance: “In my lifetime various birds

    have been steadily pushing northward and northeastward, and it follows, con–

    sequently, that the present isothermal lines of their northernmost limits

    are very much cooler than the isothermal lines that constituted limits

    twenty-five years ago. In other words, it is obvious that temperature has

    not limited the northward distribution of these birds in any way whatsoever.”

    (11) p.160). The reclamation by birds of previously glaciated territory is

    no doubt keeping pace with the reclamation by plants and other organisms,

    but the influence of temperature upon the rate of that reclamation cannot

    be ignored. With this preliminary warning of the limits of our present

    knowledge, examples of recent northward extensions in the distributions of

    organisms can be discussed.

            The effect is of course not restricted to the arctic and subarctic

    regions, but it is with these regions only that we are concerned here.

    Griscom (10; 11) has mentioned several birds which have spread northward

    in the United States recently, and Hubbs (14) has studied the question of

    recent changes in the distribution of marine fish in the pacific coastal

    waters, also of the United States.

            Northward creep of vegetation has been observed in Iceland and in

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    Norway, Sweden, and Finland. “In the forests of northern Scandinavia the

    economic benefits are of special importance. The trees are spreading

    rapidly above their former limits, and the annual rings of both pine and

    spruce show a quicker growth than they have for about two decades… Large,

    formerly bare areas are now being [ ?] invaded principally by birch and

    willow; the timberline of the mountain birch is rising higher and higher.

    Vegetation in general is becoming more luxuriant” (2). A similar creep

    northward of the tree line has been observed in Alaska. A similar studies

    of the tree line in northern Canada do not appear to have been published,

    but the northward movement of certain mammals has been observed.

            Rand (21) describes the coyote ( Canis latrans ) as the best example of

    recent change in status and distribution. The coyote has “within the present

    century…greatly extended its range northward and eastward and now occurs

    as far north as the arctic ocean.” It is now known at Point Barrow, Alaska,

    and in the Mackenzie Delta area. The red fox ( Vulpes fulva ) has been

    gradually extending its range beyond the tree line and well into the edge

    of the barren grounds. It is now recorded from southern Baffin Island (23)

    and from Southampton Island (24). Whether this extension of range is

    strictly referable to the climatic “amelioration” is uncertain; it might

    conceivably be due to increased pressure from human populations farther

    south.

            The moose ( Alces americana ) was described by Anderson (4) as increasing

    rapidly in numbers at that date, and also as extending its range northward,

    in the Mackenzie district. Again in 1924, Anderson recorded similar events

    in the moose population. The moose had formerly, according to Macfarland (20),

    been scarce in this region. Rand (21) doubts whether this increase in numbers

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    and in range of the moose can be ascribed to climatic factors, and is

    inclined instead to suppose that such fluctuations in the moose population

    are due to a combination of other factors, such as parasites, disease, and

    activities of man.

            The activities of man in the cultivation of the land, farther south

    than our present area, have long been known to affect the range of birds

    and mammals. The movement northward of the white-tailed deer ( Odocoileus

    virginianus borealis ) following the cutting of its native coniferous forests,

    is such an example which should be mentioned here (3, p.7). Reduction in the

    northern forests may also be related to the extensions of range in the coyote

    and red fox, already mentioned, and in the apparent gradual colonization of

    the barren lands by the wolverine (Gulo luscus).

            Among birds, there are many examples of northward extension of breeding

    ranges in the temperate parts of the Northern Hemisphere, including Iceland,

    but evidence of such extension in the Arctic seems to be scarce. Indeed, it

    appears as though the crossing of the tree line is a step which requires

    greater stimulation than a mere rise in temperature of one or two degrees.

    It is in fact probable that birds which habitually breed up to the limit of

    trees will not move farther north except as the tree limit does, and the

    latter movement is of course slow. There are occasional records of conifer–

    forest birds from well north of the tree line, such as that of a magpie ( Pica

    pica hudsonia ) (22) from the Dubawnt River area, Northwest Territories, but

    it is very doubtful whether such strays can be accepted as evidence of a true

    extension of normal range.

            Before leaving the subject of the possible effects of recent climatic

    change upon the terrestrial fauna, which effects, as w e i ll be apparent from

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    the somewhat scant evidence available, are not well marked nor with any

    certainty related to the climate, mention should be made of an interesting

    development in Greenland which seems to demonstrate a physiological effect

    of increasing temperatures and general amelioration of climate. Faester (9)

    has shown that the percentage of “summer skins,” or skins with thin fur

    more or less dominated by brownish color, in the commercial take from South

    Greenland has increased since 1929 from between 1.5 and 5% to 21% in 1938.

    This increase is not due to any alternation in the trapping season, nor to

    any change in handling of the skins for the Danish market. It represents

    an actual difference in the state of color change of the white and blue

    fox population during the trapping season, and Faester has related it to

    the milder climate. It is interesting to note that the increase in the

    pop proportion of “summer skins” in the catch occurred not during the

    period following the greatest rise, in the decade of the 1930’s, when the

    mean temperatures began to level off. This suggests that it is not the

    direct effect of temperature that is concerned, but an indirect effect,

    perhaps working through general conditions of nutrition.

           

    Marine Fauna

            The effects of change in the marine climate are clearly more immediate

    than those on land. The whole environment is affected simultaneously, over

    large areas, and there are few microclimates to build up special local

    conditions which obscure the picture as a whole. Marine organisms, as has

    already been pointed out, are for the most part very sensitive to small

    changes in temperature, much more so than terrestrial animals.

            Following immediately upon the hydrographic changes described above,

    brought about mainly by an increase in the heat and transport of the Gulf

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    Stream and North Atlantic Drift, there occurred sweeping changes in the

    fauna of the waters from Siberia westward to Baffin Bay. In the Barents

    Sea, the Atlantic cod ( Gadus callarias ) appeared much farther east in 1921

    than formerly, and continued to spread eastward. Along the Murman Coast,

    this eastward spread was observed in a great variety of animals, including

    the mollusk Cardium edule , and the echinoderm Echinus esculentus . Arctic

    species of fishes, such as Leptagonus decagonus and Gymnacanthus tricuspis ,

    have become scarce in this Murman area, and have been replaced by Atlantic

    species, such as Zeugopterus norvegicus and Chirolophus galerita , and even

    the mackerel ( Scomber scombrus ) and the herring ( Clupea harengus ) have

    become abundant. The herring, mackerel, and coalfish ( Gadus virens ) were

    reported for the first time from the west coast of Novaya Zemlya in 1936,

    by Agapov and Toporkov (1), who write: “The appearance of these fishes,

    aliens to the Arctic, is caused by the same factors as the appearance of

    the cod and some other fishes in the Kara Sea, namely the general warm spell

    of the past few years” (Agapov and Toporkov, quoted from Jensen) (15). The

    Atlantic salmon ( Salmo salar ) was found to have invaded the Kara River in 1932.

            The fisheries of northern Norway have been greatly increased during the

    present warm period, and the important cod fisheries around Bear Island and

    in the waters west and south of Spitsbergen are entirely a product of this

    warming effect. The contrast in the Norwegian fisheries today and those of

    the preceding colder period are well expressed in the following quotation

    from Jensen (15):

            “During the cold period something happened, which was diametrically

    opposite to what occurred in the following warm period. In the years 1902

    and 1903 arctic animals, such as the Greenland Seal ( Phoca groenlandica ),

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    the Ringed Seal ( Phoca foetida ) and the White Whale ( Delphinapterus leucas ),

    whose mass-wanderings are otherwise restricted to purely arctic regions,

    came down in enormous schools to the northern coasts of Norway and farther

    also along the west coast. Previously the fixed ice-boundary had advanced

    farther west and south than any one could remember; even in May 1902 it

    extended as a continuous wall from Spitsbergen and Bear Island down towards

    the Murman coast, not far from Varanger Fjord, presumably owing to the

    prevailing northerly and easterly winds over Spitsbergen and the Barents Sea.

    The temperature of the sea and air was noted as low. The special meteorological

    and hydrographical conditions in conjunction with the advance of the ice were

    taken to be the cause of the mass-incursion of arctic animals to Norway.

    At the same time the great cod fisheries in the northern district of Norway

    were a failure and the fishermen believed that the arrival of the seals had

    driven the cod from the coast. It might be questioned, however, whether it

    was not the changed natural conditions, which enabled the arctic seals and

    whales to thrive on the northern coasts of Norway, which had the opposite

    influence on the boreal cod and forced them to go elsewhere.”

            The history of the Spitsbergen fishery is recorded elsewhere in this

    Encyclopedia . It will be enough here to mention that between its beginning

    in 1874 and the present day, there was a period, from 1883 to 1926, when

    colder conditions returned and the fishery disappeared.

            In the waters around Jan Mayen, Atlantic cod and herring were taken in

    1930 and 1931, but not in commercial quantities. The Michael Sars expedition

    of 1900, under the direction of Johan Hjort, had found no food fishes at

    Jan Mayen.

            Perhaps the most spectacular of all these faunal changes has taken place

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    in the waters of Greenland, especially West Greenland, owing to the increased

    activity and heat content of the Irminger Current, a branch of the North

    Atlantic Drift, which turns north and then west, in the region southwest

    of Iceland, to meet the cold East Greenland Current and, together with the

    latter, taking part in the formation of the West Greenland Current. The

    list of Atlantic animals that have appeared or increased in range in West

    Greenland waters since the beginning of the warm period (about 1917) is

    large, and includes the following:

            Atlantic cod appeared in increasing quantities and farther north each

    year. This process, with the associated development of fisheries in Greenland,

    is described in detail elsewhere (see “Greenland Fisheries”). The cod

    came originally from Iceland, and gradually became established as a breeding

    stock in the fjords and on the banks of West Greenland. In 1929, a haddock

    ( Gadus aeglefinus ) was caught in the Julianehaab district, a species which

    had never before been recorded from Greenland waters. The haddock has not

    become abundant, but other specimens have occasionally been caught since

    1929. In 1936, another first record was made, when the brosme ( Brosmius

    brosme ) was [ ?] taken in the Holsteinsborg district. The ling ( Molva

    vulgaris ) was first caught in 1928, in the Frederikshaab district, and

    the Atlantic halibut ( Hippoglossus vulgaris ), known previously only from

    the banks south of Davis Strait, has invaded the Baffin Bay coast of West

    Greenland, at least as far as the Upernivik district. The herring, pre–

    viously known in small numbers in the extreme southwest of Greenland, has

    increased its range northward at least as far as the Umanak district on

    the west coast, and was first recorded on the east coast in 1932, from the

    Angmagssalik area. It has since been seen in Scoresby Sound. The spiny

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    dogfish ( Squalus acanthias ), formerly rare in Greenland waters, has appeared

    in greater numbers from the south. The rosefish, or Norway haddock ( Sebastes

    marinus ), has become plentiful, and has now been shown to breed in West

    Greenland waters (15).

            Certain fishes, previously common in the waters of the southern part

    of Greenland, have moved northward during the present period of warmer condi–

    tions. This class includes the Greenland or fjord cod ( Cadus ogac ), which

    has become increasingly scarce in South Greenland and more abundant in the

    north; and the capelin ( Mallotus villosus ), which was formerly most abundant

    in the area south of Disko Bay on the west coast and of Angmagssalik on the

    east coast, and has now moved the gravity point of its distribution farther

    north. The capelin is now known from Thule and from Scoresby Sound. Probably

    as a result of this movement in the capelin population population, the harp seal ( Phoca

    groenlandica ) is now common in the northern part of West Greenland than

    in the south.

            One whale, the pilot whale, blackfish, or ca’ing whale ( Globicephala

    ventricosa ), formerly Globiceps melas ), has appeared in West Greenland waters

    in recent years, as far north as Disko Bay.

            These are the most obvious increases in fauna, or in faunal range, in

    Wet Greenland waters. There are also many planktonic animals and plants

    which have invaded the West Greenland Current under the greater Irminger

    Current influence. Jensen (15) mentions the medusa Halopsis ocellata as

    an example, first recorded by Kramp (18) from collections made in 1928.

    Another good example, also a coelenterate, recorded by Kramp is Hybocodon

    prolifer , another Atlantic form first taken in West Greenland by the Godthaab

    expedition in 1928 (17).



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            As would be expected, the invasion of Atlantic forms has been accompanied

    by a retreat of the strictly arctic animals. This is best exemplified by the

    northward retreat, in West Greenland, of the beluga or white whale, and the

    narwhal ( Monodon monoceros ), both of which are now rare south of Disko Bay.

    The Greenland or arctic halibut ( Reinhardtius hippoglossoides ) is another

    arctic-water species that has become much more scarce in southwest Greenland

    since the 1920’s.

            In the Canadian waters of the eastern arctic, faunistic changes are

    much less marked than in West Greenland, in accordance with the lesser degree

    of hydrographic change. Indeed, it is not possible to point to a single in–

    stance of northward extension of range, or of retreat northward, with any

    degree of certainty, partly because of the absence of good past faunal records.

    It is generally reported that the ringed seal ( Phoca hispida = Phoca foetida )

    is now less abundant in Ungava Bay and the region south of Hudson Strait

    than in former decades, but figures are lacking, and moreover if any decrease

    has in fact taken place, it is more than possible that it is due to human

    activity. Decreasing numbers of ringed seal have even been reported by

    residents in southern Baffin Island, but again, if the decrease is true, it

    is not possible to ascribe it to hydrographic change. The same applies to

    the drastic reduction in the distribution range of the Atlantic walrus

    ( Odobenus rosmarus ) in the past hundred years (see “Arctic and Subarctic Seals”).

            The coelenterate Hybododon prolifer , mentioned above as being first

    found in West Greenland in 1928, was taken in large numbers in Lake Harbour

    Inlet, southern Baffin Island, in 1939 and 1940 (7) (see “Marine Plankton”).

    It is impossible to know how long it has been there, but since it was not

    found in the well-worked Greenland waters until 1928, it is very probable

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    that it is a fairly recent arrival in Hudson Strait. It has since been taken

    in numbers in Ungava Bay (unpublished date).

            The capelin, whose distribution has been altered in West Greenland, is

    also of interest in this respect in the Canadian waters. It is most abund–

    dant in the northern waters of Newfoundland, and along the Labrador, particu–

    larly in the southern part. In four seasons of collecting in Ungava Bay, the

    present writer obtained only two specimens of Mallotus , and it is not known

    to the present-day Eskimos of that region. Lucien Turner, however, visiting

    Ungava Bay in the years 1882-84, records in his manuscript report (27) on the

    fishes (never yet published; the auther is here indebted to the Smithsonian

    Institution for the loan of the manuscript) that capelin had not been recorded

    within Hudson Strait until several years previous to 1884 “when a few were

    seen in the neighboring waters of George’s River.” Continuing the quotation

    from the Turner manuscript: “In the spring of 1884 they were observed in

    great numbers in that vicinity [George’s River, or, more properly, George

    River]. On the 8th of August 1884 a school of several thousand individuals

    appeared four miles within the mouth of the Koksoak River. As many as were

    desired for specimens were secured by the hand as they swam near the shore….

    This is the first instance known either to whites or natives of the appearance

    of capelin in the southern portion of Ungava Bay. They are well known to the

    Eskimo, who apply the name Kolelekuk to the caplin” (Turner 1885).

            It is at once clear that faunal conditions in Ungava Bay in 1884 were

    different from conditions in 1950. Capelin are now very rare, and they are

    not known to the natives. They are North Atlantic fishes, edging into the

    Subarctic, and they are seldom seen in swarms in water of temperature below

    6°C. (25), although they have recently been observed in very large numbers

    016a      |      Vol_III-0505                                                                                                                  
    EA-Zoo. Dunbar: Faunistic Effects of Climatic Change

    in 2°C. water in southeastern Newfoundland waters (Templeman, private

    communication). At all events, the presence of capelin in large numbers

    in Ungava in 1884 is a general indication of warmer conditions in the

    water than exist at present. And yet, as has been recorded above, Turner

    met with much more severe ice conditions in 1882 than are known today. It

    is much to be deplored that routine temperature and salinity observations

    were not kept at regular intervals in the eastern arctic of Canada in past

    decades, because it is obvious that the history of hydrography and faunal

    distribution in those waters has been varied, and the evidence brought

    together here shows that the relations between atmospheric and marine

    climate, and marine fauna, may not have been simple.



    017      |      Vol_III-0506                                                                                                                  
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    BIBLIOGRAPHY

    1. Agapov, I.D., and Toporkov, G.N. “Some data concerning the fishes

    of Novaya Zemlya.” Problems of the Arctic, vol.2, p.108.

    Leningrad, 1937. (In Russian)

    2. Ahlmann, H. “The present climate fluctuation.” Geogr.Jour ., CXII

    (4-6), pp.165-193, 1949.

    3. Anderson, R.M. “Catalogue of Canadian recent mammals.” Nat.Mus .

    Canada., Bull . No.102, 1946.

    4. ----. “Report on the natural history collections of the expedition,”

    Stefansson’s My Life with the Eskimo , Macmillan, New York,

    1913.

    5. Bailey, W.B., and Hachey, H.B. “An increasing Atlantic influence in

    Hudson Bay.” Joint Committee on Oceanography, St.Lawrence,

    N.B. 11 pp. (mimeographed). 1949.

    6. Dunbar, M.J. “Eastern Arctic Waters.” Fish.Res.Bd. Canada, Bull. No.88,

    1951.

    7. ----. “Marine macroplankton from the Canadian Eastern Arctic. II.

    Medusae, et.” Can.J.Research , D, 20, pp.71-77, 1942.

    8.----. “The state of the West Greenland current up to 1944.” Fish.Res.Bd .,

    Canada, Jour . VI (7), pp.460-471, 1946.

    9. Faester, K. “Effect of the climatic amelioration of the past decade on

    the autumn change of coat of the arctic fox in Greenland.”

    Medd.Grønl . vol.142 (2), 1945.

    10. Griscom, L. The Birds of Concord . Cambridge, Mass., Harvard University

    Press, 1949.

    11. ---. Modern Bird Study . Cambridge Mass., Harvard University Press, 1945.

    12. Hare, F.K. “The climate of the eastern arctic and subarctic of Canada

    and its influence on accessibility.” Report for the Government

    of Canada (Manuscript), 1950.

    13. Helland-Hansen, B., and Nansen, F. “Temperature variations in the North

    Atlantic Ocean and in the atmosphere.” Videnskapselskapets

    Skrifter, I. , Mat.-Naturv. Klasse, 1916 (9).

    14. Hubbs, C.L. “Changes in the fish fauna of western North America correlated

    with changes in ocean temperature.” J.Mar.Res. , VII (3),

    pp.459-480, 1949.



    018      |      Vol_III-0507                                                                                                                  
    EA-Zoo. Dunbar: Faunistic Effects of Climatic Change

    Bibliography

    15. Jensen, Ad. S. “Concerning a change of climate during recent decades

    in the arctic and subarctic…, etc.” Det.Kgl.Danske Vidensk .

    Selsk., Biol Medd. , XIV (8), 1939.

    16. Kiilerich, A.B. “The hydrography of the west Greenland fishing banks.”

    Medd. fra Komm.Danm.Fisk. og Havunders. , Ser Hydrografi, 3 (3),

    1943.

    17. Kramp, P.L. “Medusae (Godthaab Expedition 1928).” Medd.Grøn ., vol.81

    (1), 1942.

    18. ----. “A revision of the Medusae belonging to the Family Mitrocomidae”

    Vidensk. Medd.Dansk Naturh.Foren ., 92, pp.305-384, 1932.

    19. Lauzier, L. “Unusually warm surface sea-water in 1949.” Fish.Res.Bd.

    Canada, Progress Rep . Atlantic Coast Stations, No.51, p.17,

    1950.

    20. MacFarlane, R. “Notes on the mammals collected and observed in the

    northern Mackenzie district, Northwest Territories.” Proc .

    U.S. Nat.Mus., 28, pp.673-764, 1905.

    21. Rand, A.L. “The mammals of northern Canada from a utilization viewpoint.”

    Report for the Government of Canada. (Manuscript). I-XIV,

    pp.1-809, 1949.

    22. ----. “Northern records of the magpie, Pica pica hudsonia (Sabine).”

    Can.Field-Nat ., 59 (1), p.45, 1945.

    23. Soper, J.D. “The mammals of southern Baffin Island, Northwest Territories,

    Canada.” J.Mamm. , 25 (3), pp.221-254, 1944.

    24. Sutton, G.M., and Hamilton, W.J. “The mammals of Southampton Island.”

    Mem. Carn.Mus., 12 (2), 1932.

    25. Templeton, W. “The life history of the Chaplin ( Mallotus villosus O.F.

    Müller) in Newfoundland waters.” Bull . Nfld.Govt.Lab.,

    No.17 (Research), 1948.

    26. Tully, J.P. “Seasonal cycles in the sea.” Fisheries Res.Bd. Canada,

    Progress Rep . Pacific Coast Stations, No.85, pp.88-90, 1950.

    27. Turner, L.M. “Fishes.” (Manuscript report deposited in the Smithsonian

    Institution, Washington, D.C.), 1885.

           

    Max M. J. Dunbar

    Littoral Fauna of the Arctic


    Unpaginated      |      Vol_III-0508                                                                                                                  
    (EA-Zoo. Holger Madsen)

    LITTORAL FAUNA OF THE ARCTIC

           

    CONTENTS

    Page
    Introduction 1
    Geographical Delimitation 3
    Distribution of the High-Arctic and Subarctic

    Zones in Different Regions
    4
    Shore Fauna of the High-Arctic Zone 9
    Shore Fauna of the Subarctic Zone 14
    Bibliography 16



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    EA-Zoology

    (Holger Madsen)


           

    LITTORAL FAUNA OF THE ARCTIC

           

    Introduction

            The shore falls into two more or less sharply delimited divisions: the

    littoral and the supralittoral zones. The littoral is that portion which is

    periodically inundated, i.e., the tidal zone; the supralittoral is that portion

    above spring tidemarks, but affected by the sea. That part of the littoral

    which is inundated only by spring tide is usually included with the supralittoral

    zone under the name “upper beach,” while the area below is referred to, for con–

    venience, as the “tidal zone” proper.

            There is considerable variability in the extent of the two zones, depending

    upon the slope of the shore, the height of the tidal wave, exposure to wind, etc.

    Chiefly the depth of the zones is dependent upon the character of the coast,

    whether rocky or sedimentary. In its strictest sense this delimitation applies

    only to rock facies in absolutely wind-sheltered localities. Elsewhere , partly

    due to waves, partly due to capillary attraction, on sandy shores, the littoral

    area will shift upward. The downward shift of the boundary will be determined

    by the lowest point to which the waves recede. A long period of calm weather

    on an unsheltered shore may also force the line downward.

            On the upper beach, terrestrial ecological conditions prevail, being modified,

    however, by the influence of such marine factors as, for example, the salinity of

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    EA-Zoo. Madsen: Littoral Fauna

    of the bordering sea. The upper beach is also delimited in respect to other

    terrestrial biotopes by this and other marine factors. Where there is an afflux

    of fresh water, conditions are modified in a limnological direction, even in

    the tidal zone proper, brackish water or estuary conditions prevailing.

            According to the aspect of the coast, the following biotopes in the tidal

    zone can generally be discerned: ( 1 ) rock shore, ( 2 ) sand and/or gravel beach,

    ( 3 ) clay (or mud) shore, ( 4 ) mouth of stream or estuary, ( 5 ) littoral meadows,

    and ( 6 ) lagoons. The last three mentioned biotopes vary greatly and are not

    capable of sharp delimitation. Sand and clay shores present transitional stages,

    as does a clay shore to estuary, littoral-meadow, and lagoon classification s .

    Furthermore, only portions of the littoral meadows belong to the tidal zone proper,

    the remainder belonging to the upper beach.

            In regions with high tides, it is often possible to discern zones within the

    above-mentioned biotopes. The interzonation becomes less apparent where arctic

    conditions (in the broad sense of the term) predominate. Shore fauna all over the

    world present interesting ecological features because of the varying conditions to

    which they are submitted and the meeting of land and sea factors; but many special

    phenomena occur in arctic shores, as might be expected from the more severe con–

    ditions for life.

            Comparatively little is known regarding the shore fauna of many arctic regions.

    What knowledge we have is chiefly of Greenland, Spitsbergen, the Kola Peninsula,

    and Novaya Zemlya. As to conditions on the arctic shores of America and Asia,

    only scattered and casual information is available. From this, however, it is

    possible to draw a few general conclusions, especially as to the biotopes of

    rocky shores, which have been more thoroughly studied thus far. In such a habitat

    the more conspicuous species occur, species which are commonly known and which

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    are liable to be collected even when expeditions lay scarcely any stress upon

    zoological investigations. We have very few special investigations from which

    to draw; for the most part our knowledge of littoral conditions must be compiled

    from the general faunistical and zoogeographical papers that exist.

           

    Geographical Delimitation

            The geographical delimitation of the littoral zone, as shown by the actual

    distribution of animals, coincides broadly with the ones used in other parts of

    this Encyclopedia, but certain special features are apparent as regards the

    tidal zone proper.

            It is a common conception that the temperature and salinity of the water are

    decisive factors for the littoral fauna; a conception supported by Steven (21)

    and Dahl (5). As previously demonstrated by the author and strongly emphasized

    by Dunbar (7), this does not, however, apply as to whether a specific littoral

    fauna of higher animals, consisting of ( moll ) mollusks and Balanus balanoides ,

    is actually able to develop in a given geographical region. The formation of

    ice is almost wholly dependent on climate, and does not appear to be a decisive

    factor. For example, a specific littoral fauna is present in Upernivik on the

    northwest coast of Greenland but is absent in Scoresby Sound on the east coast;

    yet the climate is practically the same in the two regions. Again, a sharp

    climatic boundary is found about latitude 68°30′ N. in East Greenland, whereas

    the boundary in the littoral is slightly north of 66° N. It seems, therefore,

    that other causes are decisive here, causes which have some connection with the

    sea and its abundance of life which would also affect the sublittoral fauna

    (17; 19). According to Dunbar (7), the ocean currents are evidently a factor.

            The arctic littoral clearly falls into two regions: a high-arctic and a

    subarctic. The high-arctic region is distinguished by the lack of a number of

    004      |      Vol_III-0512                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

    forms characteristic of the littoral in other latitudes, notably the Balanus

    balanoides
    and other barnacles, mollusks, and the Hydroida Hydroida .

            We have thus good criteria for delimitation of the arctic and subarctic

    littoral regions. The southern delimitation of the Subarctic is more difficult.

    There are, however, certain species of high-arctic distribution which are also found

    in subarctic areas, and which may be taken as good indicators of the presence of

    an admixture of polar water. The southern limit of their distribution may thus

    be taken as a good guide to the limit of their subarctic region. Such species are

    the amphipod Pseudalibrotus littoralis and the mysid Mysis oculata . It is of

    interest to note that P. littoralis , within the subarctic area, is usually con–

    fined to estuaries.

            So great are the differences met with in the subarctic zone that a more

    detailed geographical subdivision is needed; and it may be predicted that one

    will be made when more accurate information is available. But from the studies

    thus far made it becomes obvious that the boundaries of the two zones are not

    due to any single factor, such as differences in temperature, salinity, etc.,

    but rather to a combination of factors not least of which are the ocean currents.

    The high-arctic region is exclusively under the influence of arctic waters, but

    the subarctic has everywhere a connection with warmer waters through the ocean

    currents. Thus, the boundaries will shift in accordance with the fluctuations

    of these currents (15).

           

    Distribution of the High-Arctic and Subarctic Zones

    in Different Regions

            In Greenland, curiously enough, the longest stretch of the coast is subarctic

    in character. Conditions on the north coast have not been investigate s d , but from

    what is known about the nature of this region it is assumed to be high-arctic.

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    The east coast, which has been investigated, is high-arctic down to a point

    immediately north of Angmagssalik, about 66° N. latitude, the northernmost

    limits for the snail Littorina saxatilis var. groenlandica, the mussel

    Mytilus edulis , the barnacle Balanus balanoides , the amphipod Jaera marina ,

    and the polychaete Arenicola marina .

            From that point southward, the east coast is subarctic. The entire west

    coast is subarctic northward to the Thule District (about 76° N.), although

    very great differences are to be found on this enormous stretch. In previous

    u: OIC? papers the author regarded the Thule District as high-arctic since the presence

    of Mytilus edulis , although probable, judging from statements made by Greenlanders,

    had not been proved. Recently, however, Vibe (verbal communication) found this

    species in large numbers up to the lowest horizon of the tidal zone in several

    Thule localities. Previously the author was inclined to reckon regions as

    being in the high-arctic zone where Mytilus , and this species only of the higher

    littoral forms, occurs in the sublittoral (as it is also reported from Novaya

    Zemlya). But now it would seem that the very occurrence of this species indicates

    an influence of Atlantic water (see also (7)).

            Since no mollusks other than Mytilus occur in the tidal zone farther north,

    the Thule District can be regarded as the northernmost outpost of the subarctic

    fauna. But in fact we must descend the coast for quite a distance southward

    (about 73° N.) to find similar conditions, for it is at that latitude that the

    L o i ttorina saxatilis var. groenlandica makes its first appearance. Still farther

    southward, at Upernivik (72°47′ N.), a rather rich littoral fauna is met with.

    There, besides the already mentioned forms, especially the littoral hydroids,

    are found the u: previously called amphipod. Which is correct isopod Jaera marina , tubificides, and a number of mollusks and

    polychaetes, which also occur in the sublittoral. Balanus balanoides was not found

    in 1936, when the investigations were made.



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            In spite of zealous search, only older specimens of Mytilus edulis were

    found at Upernivik and in the Thule District. From this fact it was concluded

    that M. edulis does not spawn every year. It is possible, however, that they do

    spawn but that the spat is unable to survive. Judging from the furrows in the

    shell, some of the specimens are very old, probably twenty years.

            A little farther southward (72°23′ N.) in the harbor of Prőven, Balanus

    balanoides makes its appearance, though few in number and restricted, especially

    by the strong prevailing current of the locality, as to areas which enjoy favorable

    conditions. At exactly what point southward continuous populations of B. balanoides

    occur is not known.

            In the Umanak District the fauna has a more distinctly boreal stamp in places

    where the freshwater influence, due to the outflow of glaciers, is not too marked,

    as was shown by the investigations of Vanhőffen (31). Arenicola marina occurs here.

            Moving southward along the coast, the fauna is of the same main composition,

    though more numerous and varied. Special littoral investigations of Amerdlok Fjord

    in the Holsteinsborg District (about 67° N.) disclose the presence of a very rich

    fauna, notably on the clay shore, where are Mytilus beds comparable in weight per

    square meter to those of boreal waters (21).

            Aside from those mentioned, no other special littoral investigations have

    been made. But much information can be gleaned from Otto Fabricius’ Fauna

    Groenlandica (1780) as to the littoral fauna in the Frederikshaab District (16).

    Fabricus’ investigations disclose the presence of a very rich littoral fauna as

    well as a large number of sublittoral species. The only characteristically arctic

    form present here is the Pseudalibrotus littoralis which, at this more southern

    latitude, is retricted to river mouths.

            The fauna of north and east Iceland resembles that on the southwest coast

    of Greenland.



    007      |      Vol_III-0515                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

            Very little is known about the littoral fauna of Jan Mayen. Becker, in 1886,

    mentioned Littorina palliata but once, and then as occurring in one locality

    only, a cave on the island (which reference needs to be confirmed). The presence

    in the supralittoral of the boreal fly Fucellia fucorum (14), would also seem to

    indicate boreal influence (14), as do certain features of the fish fauna (15).

    On the whole, however, the fauna is for the most part arctic in character, so

    that Jan Mayen may be regarded as a subarctic outpost.

            In the southwestern part of Spitsbergen (Svalbard), subarctic conditions

    prevail. Here we find Littorina sax a t a i lis var. groenlandica , Balanus balanoides ,

    some hydroids, and bryozoans. Mytilus edulis no longer exists in Spitsbergen,

    although subfossils from postglacial times have been found. Probably, because of

    its comparatively short-lived larval stage, it has not since been able to spread

    again to this region author OK? (26). In this connection, it can be mentioned that the

    snails, Skeneopsis planorbis and Littorina littorea , referred to, respectively,

    by Thiele (23) and Elton and Baden-Powell (8), have not been found in Spitsbergen

    (compare (18) and (24). The occurrence of the beetle Micralymma marinum indicates

    the arctic influence on the southern fauna here, as well as in Bear Island to the

    south of Spitsbergen. On Bear Island, Balanus balanoides are also met with in

    large numbers (30). Too little is known of the fauna of Spitsbergen to warrant

    drawing distinct boundaries, but the northern parts are probably high-arctic.

    In all probability the same hol e d s true for Franz Josef Land. At any rate, none

    of the special littoral mollusks has been reported from there.

            On the A rc sia tic-European continent, the southern limit of the subarctic may be

    drawn at Lofoten in Norway, since this point seems to be the southernmost limit

    for the arctic Pseudalibrotus littoralis as well as the northernmost limit for

    several littoral forms such as the snail Patella vulgate (6) (see (6) , especially

    008      |      Vol_III-0516                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

    1934-37). The eastern boundary of the subarctic littoral is near the entrance

    to the Kara Sea, conditions in this area greatly resembling those of northwest

    Greenland; Littorina saxatilis occurs along a wide stretch, Balanus balanoides

    more locally. However, several authors mention the occasional occurrence s of

    young B. balanoides right into the Kara Sea, borne there probably by the constant

    eastward current through Yugorski Shar. The greater part of the Kara Sea may be

    classified as high-arctic.

            The greater part of Novaya Zemlya also belongs to the arctic province, but

    in the southern part the Atlantic influence is felt, as apparent in the occurrence

    of Mytilus edulis , which for the most part lives sublittorally, as in the Thule

    District in northwest Greenland. Other manifestations of the Atlantic influence

    are the presence of Littorina palliate (24) and the occasional occurrence of

    Balanus balanoides in Matochkin Shar (22).

            High-arctic conditions prevail along the Siberian coast; Pseudalibrotus

    littoralis, however, is replaced by the Siberian species, P. birulai . In the

    Chukotsk Sea, east of Wrangel Island, subarctic conditions return, that is,

    Pacific influence reaches that far west (22). It is difficult to designate

    exactly the southern boundary of the subarctic on the western side of Bering

    Strait; out two “indicators,” P. littoralis and Mysis oculata , do not occur

    south of St. Lawrence Island, but there is evidence, nevertheless, for arctic

    influence somewhat farther south. The level of Lorenz Island is the limit of the

    subarctic on the eastern side of Bering Strait, but some arctic influence is felt

    a little farther south on the western side, in the sublittoral (3; 10).

            The whole northern coast of the American continent is undoubtedly subarctic,

    but very little is known about the fauna of this region, and conditions on the

    northern islands are quite unknown. The entire eastern coast of Baffin Island

    009      |      Vol_III-0517                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

    is subarctic, Mytilus having been found at Pond Inlet (17) and Balanus balanoides

    has been found near Cumberland sound (22). What conditions prevail on Ellesmere

    Island is now known, but it can be hazarded that the arctic zone descends some–

    what farther southward on the western side of Baffin Bay. As to Pseudalibrotus

    littoralis on the eastern coast of America, nothing is known; but the southern

    limit of Mysis oculata is at Cape Charles, Labrador (about 53° N.). The occur–

    rence of Littorina palliata would also indicate the subarctic character of the

    region (20). We must, however, remember that this species seems to extend

    farther south in America than in Europe the Iceland (24).

            Knowledge of the supralittoral is still more restricted than that of the

    littoral zone proper. The limits will be seen to follow different courses,

    corresponding more closely to the climatic limits, these in turn being affected

    by ocean currents. Roughly, it may be said that the upper beach fauna in the

    subarctic region will prove to be rather poor. The Orchestia community seems to

    appear nowhere, are judging from the work in northern U.S.S.R. , littoral beetles,

    with the exception of certain species of Micralymma , extend but a little distance

    into the subarctic. Dispersion-ecological causes may account for the absence of

    a number of littoral Hydrophlidae and Staphylinidae which are common in northern

    Iceland, subarctic Greenland, Spitsbergen, and Novaya Zemlya.

           

    Shore Fauna of the High-Arctic Zone

            Even though animals prevalent in the subarctic regions, such as mollusks,

    barnacles, and hydroids, are completely absent in the high-arctic zone, other

    animals adapted to the special shore conditions may be found. These special

    shore conditions have been specifically investigated in East Greenland only,

    but it is thought that similar conditions prevail throughout the high-arctic zone.



    010      |      Vol_III-0518                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

            The main characteristic of the fauna is that, the more severe the conditions

    the fewer the animals, both as to species and specimens. Very few examples of

    true arctic animals adapted to life on the shore are known. The only instances

    of which we can be sure are found among the order Diptera: the Muscidae Fucella

    arciiformis and F. pictipennis, and the Chironomidae, Orthocladius decoratus ,

    O. groenlandensis , O. fusistylis , and Smittia extrema . These live on the upper

    beach as adults, in lagoons and littoral meadows as larvae, as do related species

    in boreal regions.

            Since the distribution of these animals is much more dependent upon climatic

    than upon littoral conditions, and distribution will not follow the littoral

    boundaries outlined above. However, it may be said that they have a pronounced

    northern distribution. Fucellia apparently has a western distribution, having

    been reported only in Greenland and Arctic America, whereas Orthocladius decoratus

    and Smittia extrema apparently have a more eastern distribution, being known to

    occur in Spitsbergen. The staphylinid beetle Micralymma brevilingue , a few larvae

    of which have been found in lagoons in East Greenland, and M. dicksoni , of similar

    habits and occurring in northern Siberia, should also be mentioned.

            On sand shore and in sand patches on gravel shore in the tidal zone proper,

    the turbellarians Notocaryoplana arctic a have been found, as have been, on clay

    shore, Protomascrostomum groenlandicum . Both are new genera and species to the

    author’s material from East Greenland and may prove to be true arctic shore

    animals. As already stated, Pseudalibrotus littoralis is of wide arctic dis–

    tribution, being related to the shore but not exclusively bound to it and,

    though its habitats differ in the high-arctic and subarctic, occurs in both.

            The phenomenon noted in the distribution of Pseudalibrotus littoralis,

    namely, that the habitat is less restricted in the high-arctic than in more

    011      |      Vol_III-0519                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

    southern regions, is one frequently noted in the high-arctic, and may be due to

    differences in competitive conditions.

            Aside from the above-mentioned species, a few other animals occur, also

    being shore forms in the subarctic and boreal regions, again illustrating the

    notably thinned-out character of high-arctic fauna. Wherever sufficient moisture

    is present, enchytraeids occur, especially Lumbricillus lineatus in Greenland

    (but doubtless elsewhere as well), Enchytraeus albidus , and probably other species,

    if Spitsbergen, which has been especially well investigated in this respect, may

    be taken as typical. The orybatid Ameronothrus lineatus very frequently occurs,

    most often in the variety nigrofemoratus . The various biotopes occur in differing

    frequencies, salt marshes harboring an especially rich fauna.

            Other true littoral animals occur: the collemboles, Archisotoma besselsi and

    Hypogastrura viatica , and the parasitoid, Molgus littoralis .

            On rock shore the animal life is very poor, Molgus littoralis from the upper

    beach alone being know n , but it probably feeds on some small as yet unknown

    animals of the littoral lichen zone.

            In the shor e t , tomentose, algal vegetation within the tidal zone proper,

    Ameronothrus occur, in association with oligochaetes, and undoubtedly also small

    crustaceans, including several copepoda, which have also been ob served on other facies.

    In most high-arctic regions this vegetation is characterized by the absence of

    the dominant littoral algae, Fucus vesiculosus and Ascophyllum nodosum . Further,

    several amphipods can be found, of which Gammarus locusta setosus Is this correct? has been

    observed as especially common. No investigations on rock pools have as yet been

    made, but in all probability their fauna will show similarities to that of the

    lagoons. A striking feature of the rock-shore fauna is that it is not restricted

    to rock shore, all the species having also been found on other types of shore.



    012      |      Vol_III-0520                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

            The sediment facies is of course as differentiated as in other regions, but,

    in contradistinction to more southern regions, no gr an ea t differences in the compo–

    sition of the fauna can be observed. The plant life is of but slight importance,

    and the animal life of no importance.

            On the upper beach, the above-mentioned flies and chironomides occur, together

    with the littoral collemboles and mites, a large number of other collemboles (12),

    and several spiders, the most common of these being Micryphantes nigripes and

    species of Erigone Erigone (2), buried among the washed-up algae in the drift line.

    Oligochaetes are also found.

            In the tidal zone proper, on gravel and sand beach, we find Gammarus locusta

    setosus , Pseudalibrotus littoralis (the latter burrowing in the sand), and along

    with the oligochaetes, the turbellarians, Notocaryoplana arctica and Monocelis fusca ,

    these last two being absent where strong freshwater influence prevails and, finally,

    several harpacticoids, these being known as brackish-water forms.

            Clay (or mud) shore has been studied in one locality only. There the forma–

    tion was dependent on the outflow of a glacier, and it presented, on the whole,

    the same picture as to fauna as had been found on sand shore, with a few exceptions.

    The exceptions were the presence of a special turbellarian, Protomacrostomum

    groenlandicum , not specifically determined ostracodes, and the harpacticoid

    Bradya typica , which is always associated with a clay bottom. In stream mouths,

    where extensive flats are often formed, and in lagoons, the usual animals may be

    found. In stream mouths they are rather scattered. Here, the larvae of the

    shore flies and midges, which occur characteristically in sheltered places, are

    apparently coincident with accumulated organic matter, just as on the upper beach

    animals occur only where vegetation is present. In the water of the stream mouths

    and lagoons, Laophomte strőmi and species of Tachidius live, these harpacticoids

    013      |      Vol_III-0521                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

    being known as brackish-water forms. The young of Cottus quadricornis prefer to

    live in these places as well. Here, the small fishes are hunted by gulls, the

    smallest animals being also preyed upon by small waders, although these birds

    do not, as in boreal regions, nest on the shore. Geese crop close the vegeta–

    tion of the littoral meadows which are characteristically covered with a mixture

    of the algae Puccinellia phryganodes and Carex ursina .

            In the soil there is a teeming life of orybatids and collemboles and, where

    there is a great deal of moisture, myriads of oligochaetes, nematodes, and pro–

    tozoans, often rotifers and tardigrades as well, this latter life being especially

    intensified in the film of cyanophyceans and diatoms occurring in the tidal part

    of the lagoons and littoral meadows. Spiders abound in the upper beaches.

            The afflux of fresh water is the most important factor modifying conditions

    of life in the salt marshes, the richest development of animal life occurring

    where such an influence is felt. But, although the animals may be numerically

    very considerable ( Ameronothrus up to about 50,000 per square meter, oligochaetes

    and chironomides larvae about 12,600), the weights, which never exceed 20 grams,

    are negligible compared with those of the marine communities.

            It is an interesting fact that in the arctic zones, particularly in the

    high-arctic, plants and animals are not so strictly bound to the shore as in

    more southern regions. This is especially noticeable in places where, from some

    dispersion-ecological causes, fewer species are present. Molgus littoralis can

    be found rather far from shore (16), as is true of the same species and Bdella

    decipiens in northern Spitsbergen (27; 29). A number of shore plants, too, are

    sometimes found far from shore, in places manured by birds or human beings, for

    example, in the ruins of Eskimo houses. The spider Ameronothrus lineatus has

    been found on bird cliffs on Bear Island and Ameronothrus and the shore oligochaete

    014      |      Vol_III-0522                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

    Lumbri o ci llus profugus have occurred in mosses on Jan Mayen (4; 28). Again, a

    number of animals found in the tidal zone farther south tend to be found lower

    down (in the sublittoral) in arctic conditions, and this tendency becomes more

    marked the more completely arctic the climate. This is found also, oddly enough,

    in the Baltic, where, for instance, several littoral mollusks occur in much

    deeper water than elsewhere (11; 17). It is possible that in this case also

    the diminished competition due to the smaller number of species may be an impor–

    tant factor.

           

    Shore Fauna of the Subarctic Zone

            As already stated, a great variety of fauna can be found within this zone.

    In fact, in its more southern portions or where conditions are for some reason

    particularly favorable, a fauna as rich as or even richer than that of many

    boreal regions occurs. A number of special investigations have been made, notably

    along the Murman coast (11) and in West Greenland (18 ref. right? ; 21). The presence of Mysis

    oculata , which is found almost everywhere, and the occurrence of Pseudalibrotus

    littoralis as an estuarine form are outstanding characteristics of this zone.

    The arctic influence on the fauna is felt in the absence of a number of boreal

    forms. This is particularly true of the fauna of islands, such as Iceland, where

    more special conditions prevail.

            Where the fauna is submitted to the influence of freshwater factors (rivers

    and glaciers), a deterioration takes place. But where pure marine conditions

    are provided, we find a teeming life in the littoral.

            On rock shore, the Balanus balanoides and Mytilus edulis associations dominate,

    but there is a great variety of other mollusks and also crustaceans and worms,

    these latter partly in connection with a strong vegetation of higher algae. On

    beaches with sand and gravel, there is a rich life of burrowing worms and mussels.

    015      |      Vol_III-0523                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna

    On clay shore a still more luxurious life occurs, with a greater number of

    individuals and the specimens being also of larger size. As in boreal regions,

    the clay shore frequently develops into regular beds of Mytilus , many of the

    specimens being as large as those found in boreal regions. There is a rich

    epifauna of the same character as that found on the rock shore. Communities

    of Macoma balthica-Arenicola marina abound, as do communities of Pygospio elegans ,

    the latter occurring in river mouths as in boreal regions. A Hydrobia ulvae

    community occurs on the Murman coast, but is missing both in Iceland and Greenland,

    probably for reasons of dispersal. A Corophium volutator community seems to be

    missing everywhere.

            On the upper beach, where climatic conditions make themselves most clearly

    felt, the arctic influence on the fauna is very apparent, asserting itself

    characteristically, as mentioned above, in the total absence of an Orchestia

    community. In many places shore beetles abound. Backlund (1) has recently

    contributed to our knowledge of these littoral beetles by making collections in

    the Petsamo district of northern Finland.



    016      |      Vol_III-0524                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna


    BIBLIOGRAPHY

    1. Backlund, H.O. “Wrack fauna of Sweden and Finland, ecology and chorology,”

    Opusc.Entom . Suppl. 1945.

    2. Braendegaard, J. “The spiders (Araneina) of East Greenland. A faunistic

    and zoogeographical investifation,” Medd.Grøenland, vol.121,

    no.15, 1946.

    3. Broch, Hj. “Noen dyregeografiske trekk i nordhavenes bunndyrverden,”

    Norsk. Geogr.Tidsskr . vol . 6, no.6, pp.1-16, 1937.

    4. C Č ernosvitov, L. “Sur quelques oligoch e è tes de la r e é gion arcti c que et des

    I Î les Faer-Oer,” Annalses Sci.Nat. vol. Ser. 10, no. vol. 14, pp.65-111, 1931.

    5. Dahl, E. “On the s S maller a A rthropoda of m M arine a A lgae, e E specially in the On the s S maller a A rthropoda of m M arine a A lgae, e E specially in the

    p P olyhaline w W aters off the Swedish West c C oast,” p P olyhaline w W aters off the Swedish West c C oast,” Lund, Gleerup, 1948. Undersőkningar över

    Oresund , vol.35 . 1948. (Gleerup, Lund, Sweden,)

    6. Dons, C. “Norges strandfauna, I-XIX,” Norske Videnskaps-Akad. Forh.

    vol.5, no.50; vol.6, no.11, 24; vol.7, no.2, 25, 30; vol.8, no.9.

    12,20,21; vol.9, no.20,42,43; vol.10, no.8, 9, 12, 13, 14, 1932-37.

    7. Dunbar, M.J. “Note on the delimitation of the arctic and subarctic zones,”

    Canad.Field Nat. vol.61, no.1, pp.12-14, 1947.

    8. Elton, C.S., and Baden-Powell, D.F.W. “On a collection of raised beach

    fossils from Spitzbergen,” Geol.Mag . Lond. Vol.68, pp.385-405, 1931.

    9. Gisl e é n, Torsten. “Epibioses of the Gullmar Fjord. I. & II,” Kristinebergs

    Zool.Stat. 1877-1927. Papers no.3,4, 1930. (Svenska Vetenskapsakad.

    Skriftseries .)

    10. Gurianova, E. “Beiträge zur Kenntnis der Isopodenfauna des Pazifischen

    Ozeans IV,” Zoologischer Anz . Vol.114, pp.250-65, 1936.

    11. ----, Saks, I., and Ushakov, P. “Litoral Zapadnogo Murmana.”

    (The littoral of West Murman.), Leningrad. Gosudarstvennyi Gidrol.

    Inst. Issled.Morei SSSR, vol.11 , pp.47-104, 1930.

    12. Hammer, M. “Studies on the Oribatides and Collemboles of Greenland,”

    Medd. Grønland vol.141, no.3, 1944.

    13. Henriksen, K.L. “A revised index of the insects of Grønland,” Ibid . vol.119,

    no.10. 193 0 9 .



    017      |      Vol_III-0525                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna. Bibliogrpahy

    14. ----, and Lundbeck, Will. “Landarthropoder (Insecta et Arachnida),”

    Ibid . vol.22, pp.481-823, 1917.

    15. Jensen, Ad.S. “Concerning a change of climate during recent decades

    in the arctic and subarctic regions, from Greenland in the west

    to Eurasia in the east, and contemporary biological and

    geophysical changes,” Danske Vidensk.Selsk. Biologiske Medd .

    vol.14, no.8, pp.1-75, 1939.

    16. Madsen, Holger. “Biology of a littoral mite,” Nature , Lond. Vol.139,

    no.3521, p. 715, 1937.

    17. ----. “Investigations on the shore fauna of East Greenland with a

    survey of the shores of other arctic regions,” Medd.Grønland

    vol.100, no.8, 1936.

    18. ----. “Some zoogeographical corrections,” J.Conch . vol.21, pp.9-10, 1938.

    19. ----. “A study of the littoral fauna of Northwest Greenland,” Medd.Grønland

    vol.124, no.3, 1940.

    20. Packard , A.S. “On the recent invertebrate fauna of Labrador,” Boston

    Soc.Nat.Hist. Mem . vol.1, 1865.

    21. Steven, D. “The shore fauna of Amerdloq fjord, West Greenland,”

    J.Animal Ecol . vol.7, pp.53-70, 1938.

    22. Tarasov, N.L. “K faune usonogikh rakov ( Cirripedia thoracica ) Severnogo

    Ledovitogo Okeana. III.” (Contribution to the fauna of

    Cirripedia thoracica of the Arctic Ocean. III.), Leningrad.

    Arkticheskii M N auchn-Issled.Inst. Trudy vol.50, pp.35-59, 1937.

    23. Thiele, J. “Arktische Loricaten, Gastropoden, Scaphopoden und Bivalven,”

    Fauna Arct . vol.5, pt.2, 1928.

    24. Thorson, G. “Marine Gastropoda Prosobranchiata,” Zool. Iceland vol.4,

    no pt. 60, pp.1- 149 150 , 1941.

    25. ----. “Marine Gastropoda Prosebranchiata. Zool. East Greenland,”

    Medd.Grønland vol.121, no.13, 1944.

    26. ----. “Reproduction and larval development of Danish marine bottom

    invertebrates, with special reference to the plan e c tonic larvae

    in the Sound (Øresund),” Denmark. Komm.for Fisk.-og Havunders.

    Medd.Ser.Plankton vol.4, no.1, 1946.

    27. Trägårdh, J. “Acari,” Medd.Grønland vol.43, no.14, 1917.

    28. ----. “Monographie der arktischen Acariden,” Fauna Arct . vol.4, no.1, 1904.



    018      |      Vol_III-0526                                                                                                                  
    EA-Zoo. Madsen: Littoral Fauna. Bibliography

    29. ----. “Zur Kenntnis der litoralen Arten der Gattung Bdella Latr . ,

    Svenska Vetenskapsakad. Bihang Handl . vol.27, no.4, p.9, 1902.

    Arther 30. Urban, W. d’. “Zoology of Barents Sea,” Annals & Mag.Nat.Hist . vol.5,

    no.6, 1880.

    31. Vanhöffen, E. “Die Fauna und Flora Grønlands,” Drygalski, Erich von. Grønland - Expedition der Grønland - Expedition der

    Gesellschaft fűr Erdkunde zu Berlin 1891-1893 Gesellschaft f ű r Erdkunde zu Berlin 1891-1893 . Berlin, Kűhl, 1897. vol.2.

           

    Holger Madsen

    Benthonic Fauna of the Arctic and Subarctic Seas


    Unpaginated      |      Vol_III-0527                                                                                                                  
    EA-Zoology (Hjalmar Broch)

    BENTHONIC FAUNA OF THE ARCTIC AND SUBARCTIC SEAS

            This manuscript was accompanied by 11 maps. Because of the high price

    of reproducing such maps, only a few submitted will be used in Encyclopedia

    Arctica . The selection of the number of these maps will be determined by

    the publisher, and the choice of those used should be made in conjunction

    with a representative of the publisher. All maps are, therefore, being held

    at the Stefansson Library until a selection can be made.



    001      |      Vol_III-0528                                                                                                                  
    EA-Zoology

    (Hjalmar Broch)


           

    BENTHONIC FAUNA OF THE ARCTIC AND SUBARCTIC SEAS

            A cursory review of the benthonic or sea-bottom animal world of the arctic

    seas reveals some conflicting features. By comparison with the numbers of species

    in temperate seas, the fauna must be character ia z ted as poor. This puts a stamp

    of uniformity on the fauna which is further emphasized by the richness in individual

    specimens. For, though the species are few, the number of individuals is, in

    most cases, comparatively large. The zoologist is, therefore, inclined to charac–

    terize the fauna as rather uniform or poor, whereas from the point of view of the

    abundance of individuals it may be said to be rich.

            Although ecologists generally maintain that the number of individuals is

    large in the arctic seas, where conditions are apparently unfavorable to the

    existence of many species, our recent investigations make it by no means easy to

    arrive at an explanation. The cause may be found in the obvious tendency of

    arctic animals to shorten their larval, planktonic or passively floating period

    of life, and to extend the nektonic or actively swimming life. These tendencies

    are common to the benthonic fauna of the Arctic as well as Antarctic, which leads

    to the supposition that the phenomenon must somehow be correlated with low

    temperatures.

            Ecological investigations in Greenland waters, more especially by Gunnar

    Thorsen, have to a certain extent thrown light upon the question. Since the

    002      |      Vol_III-0529                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    phytoplankton has but a short period of abundance in the icy seas and since the

    sea fauna depends upon it for nourishment, the larval development must be finished

    during these short periods of abundance. Either this or the further development

    of the animal must proceed in the body cav o i ties of the adult. The theory is

    plausible; but it scarcely explains the numerical abundance of individuals in

    every species and in most localities, such abundance not being apparently con–

    sistent with recurrent seasonal scarcity of food.

            No adequate reason has as yet been found to explain why the arctic benthonic

    fauna shows this tendency to develop great numbers of individuals and their

    apparent gregariousness. As an example of such tendencies, 2,000 specimens of

    the brittle star, Ophiura nodosa , have been taken at one station in the Kara Sea.

    Similarly, more than 400 specimens of the large crab, Chionectes opilio , have

    been taken in single hauls in eastern Siberian waters and more than 1,000 specimens

    of the cumacean crusteacean, Diastylis sp., in one catch with a dredge by the Vega

    expedition working in the same sea. In the Barents Sea, the Norwegian steamer

    Michael Sars, Michael Sars, in 1902, caught in a trawl more than one ton e of sponges, Geodia sp.,

    and on another occasion, near Jan Mayen, more than a barrelful of the small mussel Pecton

    groenlandica
    . Ossian Sars reports from the Norwegian North Atlantic Expedition

    that the trawl near Spitsbergen came up positively filled with the sea lily

    Antedon eschrichti . Many more such hauls have been reported.

            Such occurrences seem to be more frequent in eastern Siberian waters than in

    the Kara Sea and farther westward. Data concerning such phenomena in arctic

    American waters are as yet lacking. It must be noted, too, that, due probably

    to the limitations and selective nature of the methods employed, the data on

    bottom samplings by Russian zoologists make no mention of such gregarious

    tendencies in arctic waters investigated by them. Moreover, a complete evaluation

    003      |      Vol_III-0530                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    of animal life cannot be made on the basis of bottom samplings, since vagile

    benthonic animals almost entirely escape and thus elude investigation.

            As with other individuals among arctic animals, which are larger than in

    temperate regions, the benthonic fauna of the Arctic shows a vigorous develop–

    ment as to size. On the other hand, recent investigations have revealed a

    slower rate of growth in arctic animals. The potency of growth being, however,

    independent of its swiftness, this does not involve a contradiction. In graphic

    terms, we may describe growth as proceeding along an ascending curve, the rise

    being less steep the lower the temperature. The metabolism, however, increases

    almost parallel with the surface of the individual, proceeding, as another potential

    curve, more steeply with increased temperatures. The final size of the individual

    is reached when the two curves cross (where the metabolism equals the potency of

    growth). This point will be reached at smaller size under higher temperatures,

    the growth continuing at lower temperatures - provided there is no interference

    from accidental factors such as lack of food, variations in salinity, etc.

            The inference may justifiably be drawn that benthonic animals of the Arctic

    are longer lived than are those of temperate or tropical waters. In other words,

    we may hazard the statement that the total metabolism of the fauna of arctic seas

    is rather strongly retarded and that the causal factor is the prevalence of low

    temperatures.

            A vertical or bathymetric study of ar t c tic waters shows less stratification

    in clearly separated layers than is the case with marine life in temperate or

    tropical regions. In warmer seas three bathymetric zones can generally be clearly

    distinguished: ( 1 ) an upper region of the costal banks (the continental shelf),

    with a depth of some 400 to 600 meters; ( 2 ) an intermediate or archibenthal region,

    with a depth of about 1,500 or 2,000 meters; and, ( 3 ) farthest down, the abyssal

    004      |      Vol_III-0531                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    region. Recent investigations have shown that, in arctic waters, the two deeper

    levels are more confluent faunistically than elsewhere, although the special

    facies (ooze) of the greatest depths still act selectively upon the animal world.

    Species, for instance, which occur mainly along the slopes of the central arctic

    basin are often met with in the deeper and icy cold strata of the Norwegian Sea,

    and typical s e pecies from the abyssal depths of that sea are often, in higher

    latitudes, found more or less accidentally in rather shallow water, even in the

    shelf sea. Nevertheless, it is convenient to treat the deep sea and the shelf

    sea (the sea along the coastal banks) separately. We shall begin with the deeper

    waters where the fauna is comparatively poor.

            A glance at the charts of the northern seas reveals that the deep sea of

    the Arctic ( below a 600-meter depth) falls into three sections. The great central

    polar deep surrounding the North Pole communicates with the deep of the Norwegian

    sea, traversing the Nansen Ridge between Spitsbergen and North Greenland, the

    shallowest part of the ridge being situated some 1,000 meters below the level of

    the sea. The icy cold depths of the Norwegian Sea are thus, as it were, an inte–

    gral part of the arctic deep sea, though separated from the warmer Atlantic deep

    sea by the shallow ridge in the Faeroe Channel, which is only about 600 meters

    below sea level. To the south, this deep borders the Atlantic deep waters in

    Davis Strait, elsewhere is separated from the polar deep by the shallow sounds

    between the arctic islands and Greenland. Finally, the deepest parts of the Okhotsk

    Sea form a basin effectively isolated from the polar deep, although these portions

    must be ranged for study with the arctic deep waters.

            Our knowledge of the deepest parts of the central polar deep is very limited.

    This is partly because of the difficulties of operating dredging gears from ice

    surfaces and partly because so few expeditions equipped for deep-sea investigation

    005      |      Vol_III-0532                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    have crossed it. The Russians have occasionally collected specimens in the

    deep sea along the Siberian slopes; but in many cases their publications are

    not readily accessible. Largely because of the impracticability of carrying

    out deep-sea work along the North American arctic coasts, very little is known

    as to the benthonic fauna of these regions. Nevertheless, from the scattered

    and inadequate information available to us, we can draw a few general conclusions.

    The data obtained by the expeditions which have worked along the Nansen Ridge and

    north of Spitsbergen prove the uniform character of the fauna in the deeps of the

    Norwegian Sea and of the central polar basin.

            On the whole, the productivity of the lowest depths (2,000 meters and more)

    is slight. The ocean bottom being always covered with Globigerina or Biloculina

    ooze, the only attached animals that can exist there are those that have developed

    special “root systems” which enable them to fix themselves in the soft bottom

    without being drowned in the mud. An example of such adaptation is the Ilycrinus

    carpenteri , a sea lily which is common to and characteristic of the arctic

    abyssal deep. The sea slugs Kolga hyalina and Elpidia glacialis are also found,

    the latter being met with in shallower depths at higher latitudes and occasionally

    even in the deepest part of the coastal banks. Also found in the greatest depths

    of the central Arctic Sea are the following: an isopod crustacean, Mesidothea

    megalura ; the amphipod crustaceans, Bruzelia dentata and Harpinia abyssi ; the

    mysidaceans, Pseudomysis abyssi (the only species known of this genus) and

    Boreomysis scyphops ; the blind prawn, Bythocaris leucopis , and its near relation

    B. payeri , the latter species also ascending to somewhat shallower parts of the

    ocean deeps.

            In the abyssal regions below 1 , 000 meters, the lamellibranchiate, Peston

    frigidus , is perhaps the most common and characteristic. At the same depth occur

    006      |      Vol_III-0533                                                                                                                  
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    marine snails, Neptunea mohni , Natica bathybii , and Bella ovalis . One of the

    most interesting of the benthonic fauna of these icy depths is the red liparid

    fish, Rhodichthys regina , which has not as yet been found in depths of less

    tham 1,150 meters.

            It is interesting to try to trace the origin of the arctic abyssal fauna

    by looking for related species in other oceans. Thus far such speculations have

    been inconclusive, but certain interesting facts do emerge. For instance, the

    genus Ilycrinus is restricted to the Pacific-Antarctic regions, whereas the

    genus Bruzelia , though apparently it does not occur in the Pacific, has been

    found outside the Arctic in shallower North Atlantic waters. The Harpinia abyssi

    and the Bythocaris pa p y eri are among the rare abyssal arctic fauna which are

    occasionally met with in the Atlantic deeps bordering the Arctic. On the other

    hand, the genus Mesidothea , of which there are but four known species, is

    entirely restricted to the arctic region and it may, therefore, be concluded that

    it originated there. Apparently, then, the benthonic arctic fauna may have been

    in part recruited from neighboring Atlantic and Pacific waters, but it also in–

    cludes many species indigenous to the Arctic.

            The upper portions of the arctic deep sea, known as the archibenthal or

    intermediate region, has a richer and more varied fauna, not counting the

    occasional visitors from shallower waters. The reason for this is the more

    varied bottom facies encountered above the “mud line.” The zone, however, cannot

    be clearly delimited. Some species, such as the above-mentioned sea slug- Elpidia

    glacialis , are found to be, especially in higher latitudes, very common in the

    upper layers of the deep sea, whenever the special facies (soft, muddy bottom)

    exists, and other species, such as the sea star Tylaster willei , are found at

    such varying depths that we cannot determine with any certainty at what depth

    007      |      Vol_III-0534                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    to assign them as characteristic. A third echinoderm, the feather star Poliometra

    prolixa
    , decidedly belongs to the upper part of the deep-sea region, but speci–

    mens of it have been rather frequently met with in abyssal depths and in the

    deeper portions of the “shelf” sea. The only seas urchin endemic to the arctic

    deep sea, Pourtalesia jeffreysi , is similarly found occasionally in other zones

    of the Arctic. The squid, Cirroteuthis mulleri , unique in this among its kind,

    is always found at depths ranging from 550 to 2,300 meters and at temperatures

    below 0°C. Among the crustaceans, the mysids, Parerythrops spectabilis and

    Erythrops glacialis, are found characteristically in the upper strata of the

    deep-sea region, together with the barnacles Scalpellum hamatum and S. striolatum ,

    both of which seem to prefer the border layers between the intermediate and abyssal

    zones.

            One of the most characteristic species of the arctic deep-sea region is the

    fascinating sea feather, Umbellula er c rinus , the nake s d stalk of which may some–

    times reach the imposing height of 2 meters, carrying on its top a bouquet of

    large, flower-like polyps. The species seems to prefer the upper parts of the

    deep sea, being usually found at a depth of 1,300 meters but smaller specimens have

    also been found in shallow waters, at a depth of but 180 meters in the Siberian seas.

    Its habitat is restricted to Greenland waters, the Norwegian Sea, and eastward as

    far as 87°04' E. at 79° N. latitude, and is, therefore, an eastern arctic species

    (see Fig. 1). The species is not found east of the New Siberian Islands or along

    the arctic coasts of North America.

            Of interest to note is the case of the Umbellula encrinus which , because of

    its short-lived and but feebly vagile larval stage is practically incapable of

    penetrating into new regions, is nevertheless comparatively numerous in the deeper

    parts of the isolated arctic deeps of Baffin Bay. The fauna of this basin is

    008      |      Vol_III-0535                                                                                                                  
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    on the whole of the same type as that of the great central polar deep and the

    icy depths of the Norwegian Sea. For explanation, it is natural to cite the

    polar currents which, after rounding the southern end of Greenland, continue

    northward along the western Greenland coast into the northern part of Davis

    Strait and Baffin Bay.

            Another detached deep-sea basin of arctic waters, the intermediate abyssal

    depths of the Okhotsk Sea, will show, it is thought, quite another picture when

    the results of the many Soviet expeditions are available. From the scattered

    data now at hand we can reach some general conclusions. It may be expected

    that species other than the sea anemone Amphianthus margaritacea will be found

    to be common to the deep-sea regions of the Okhotsk Sea, the Norwegian Sea, and

    Baffin Bay. At all events it is known that the alcyonacean (octocorallan) fauna

    clearly exhibits an aberrant aspect: benthonic species common to the Pacific

    abound in the Okhotsk Sea, some of them having developed into characteristic

    local species. The data accessible to us show with certainty that the fauna of

    the Okhotsk deep sea is much richer in species than the central polar deep,

    probably due to a strong influx from the Pacific.

            Returning to the benthonic life of the central Arctic, Ekman summed up, in

    1935, the species endemic to the arcti d c deep sea as follows: (1) entirely abyssal

    (below 1,000 meters), 85 species; ( 2 ) mainly abyssal, in the archibenthal region

    (below 550 meters), 60 species; and ( 3 ) predominantly archibenthal, 80 species;

    total endemic arctic deep sea, 225 species. To this number must be added a

    great series of species not restricted to the arctic deep sea but more or less

    common to both arctic and boreal deep seas or even the abyssal regions of other

    oceans. We must also include several species which are outstandingly eurybathic,

    that is to say, common to both deep sea and shallower waters. There are, furthermore,

    009      |      Vol_III-0536                                                                                                                  
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    some eurythermal species which are apparently independent of differences in

    temperatures. S A ccording to Ekman s summary of these, no less than 560 species

    of metazoans have been observed living in the arctic deep sea, of which about

    40% may be characterized as endemic.

            In the shallower parts of the arctic seas, the picture is even more compli–

    cated and blurred, especially in the so-called “lower arctic area.”

            Here, quite naturally, a strong influence from the boreal regions is apparent

    in the fauna. Species of distinctly arctic character, such as the bivalve

    Portlandia (Yoldia) arctica, the brachiopold Hemithyrus psittacea , or the brittle

    star Ophiopleura borealis , exist side by side with species which are as boreal as

    arctic in appearance. Examples of the boreal arctic fauna are the bivalves

    Astarte banksi and A. compressa , the brittle star Ophiura sarsi , the deep-sea

    prawn Pandalus borealis , etc. Among these are several species of predominantly

    boreal character. Such transitional border areas of the Arctic are the northern–

    most parts of the Pacific Ocean, the Atlantic coastal banks of southern Labrador,

    the northern borders of the Newfoundland banks, the waters along the greater part

    of the West Greenland coast, the north coast of Iceland, the Barents Sea, and the

    western coastal waters of Spitsbergen.

            In the shallower coastal regions of the North American archipelago, the

    northern Alaskan coast, as well as in the shelf sea of Siberia, Bering Strait,

    and westward to Novaya Zemlya, and the banks around Franz Josef Land, few if any

    boreal elements are apparent in the benthonic fauna, which is emphatically

    high-arctic in character.

            Bottom samplings from this high-arctic coastal area show several endemic

    arctic species, and many species seem to be restricted to their special domains

    within the area. Whereas a typical shallow-water species, such as the

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    lamellibranchiate ( Portlandia (Yoldia) arctica is entirely circumpolar in its

    distribution, we find that the endemic arctic isopod Mesidothea has developed

    one species, M. sibirica , which is restricted to the Siberian coastal waters

    from the Kara Sea to Bering Strait. It can be ha z sarded that parallel instances

    of such adaptation will be found eventually in the coastal waters of arctic

    North America, where the more or less isolated areas in the sounds of the archi–

    pelage provide almost ideal conditions for the development of local races or species.

    The estuaries of the great Siberian rivers and their environs with comparatively

    brackish water also harbor characteristic local species of varieties, such as

    the amphipodous crustacean ( Pseudalibrotus birulai , to mention one characteristic

    example. Similar conditions no doubt also prevail in the shallower waters of

    arctic North America, giving rise to similar results.

            In the eastern, or European and Siberian, parts of the Arctic Sea, several

    expeditions have explored the benthonic fauna of the shallower water and have

    clearly demonstrated that the distribution of the species is dependent upon

    the currents. In the arctic regions this is, on the whole, more evident in

    benthonic than in pelagic life and, among the benthonic fauna, is more obvious

    in species with short-lived and feebly vagile larval stages than in the more or

    less actively moving pelagic fauna. Dealing in terms of centuries-old develop–

    ment, we may say that routes followed in the distant past can less easily be

    traced, the more actively mobile the species. The study of the more free-floating

    benthonic species and their recent distributions has, however, not only demon–

    strated the routes of immigration but also, in some cases, g thrown light on

    their geographic origins and suggested an explanation as to why many of them

    have not as yet been able to attain the circumpolar regions.



    010a      |      Vol_III-0538                                                                                                                  
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            Owing to the greater intermixture of boreal of even more southerly species,

    the subarctic coastal waters harbor a much richer fauna than do the high-arctic

    regions. Thus the benthonic animal world of the Barents Sea is very rich in

    species as compared with that of the Kara Sea, and it is on the whole obvious

    that the numbers of species decrease toward the east in these waters, the more

    boreal species gradually diminishing. The minimum is evidently attained at the

    New Siberian Islands, or between these and Wrangel Island. Here, too, we encounter

    the first influence of the Pacific in the amphipods, isopods, and shrimps (for

    example, the Spirontocaris macilenta Spirontocaris macilenta ), which, because of a certain amount of

    mobility, are able gradually to advance, independent of the weaker ocean currents.

            The characteristics of these Pacific-Arctic regions recall those of the

    arctic waters affected by the Atlantic of Gulf Stream. At the northernmost parts

    of Norway the current has almost lost its Atlantic character but, the temperatures

    being somewhat higher than those of arctic water s , some boreal and boreal-arctic

    species may still be found in the Barents Sea and even to the north of Spitsbergen

    and Novaya Zemlya. However, on the northern side of the New Siberian Islands

    the last remnants of the Atlantic current have been so cooled that, given their

    greater salinity and resultant greater specific gravity, they sink into the polar

    deep along the arctic Siberian slope. The edges of the Siberian shelf north of

    the New Siberian Islands, or somewhere between them the Wrangel Island, are the

    farthest limits of the benthonic zooplankton of Atlantic origin which are free-

    floating or have a short - lived and passively vagile larval stage.

            Thus far we have, in our discussion of the possible origins of the benthonic

    fauna of the Arctic, referred only to the abyssal regions. In the upper, inter–

    mediate or archibenthal parts of the arctic deep-sea region, and the adjacent

    deeper parts of the coastal waters occur a great series of species which are

    011      |      Vol_III-0539                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    sometimes both boreal-Atlantic and arctic. To these must also be added several

    species of the deeper, cold area of the Norwegian Sea and adjacent waters of

    the Arctic which are clearly related to species in the Atlantic deep sea.

    Zoologists long ago demonstrated the existence of such so-called “pairs of

    species,” the one existing in arctic waters or the “cold area” of the Norwegian

    Sea, the other being found in the Atlantic to the south of the submarine ridge

    which extends from Scotland to Greenland. In several cases the species are so

    deceivingly similar that they are, by former taxonomists, identified as one and

    the same. Such was the case with the sea feathers, Umbellula encrinus (of the

    Arctic) and U. lindahli (Atlantic intermediate region); the lamellibranchiates,

    Pecten frigidus (arctic deep sea) and P. fragilis (Atlantic deep sea); the

    starfish, Bathybiaster vexillifer (Arctic) and B. robustus (Atlantic); and

    several others. In some species, for example the starfish ( Pontaster tunisspinus

    or the brittle star Ophiocten sericeum, the characteristically different individual

    groups that have developed in the cold area and the Atlantic deep sea were hitherto

    regarded as “varieties,” the morphological differences being deemed too small for

    a taxonomic distinction of separate species. In the large deep-sea pycnogonid,

    Colossendeis angusta , specimens from the “cold area” and from the Atlantic deep

    sea differ in proportions so that, although it is almost impossible to ascribe

    a locality to a single specimen, it is quite easy to do so when a number of

    individuals from, the two areas are seen side by side. It is, however, still

    frequently impossible to decide with certainty whether we have to deal with

    separate species or merely with variants of species.

            Further extremely interesting examples of closely related species are:

    the Sabinea hystrix (Atlantic), S. sarsi (Boreal), and S. septemcarinata (Arctic)

    of the Atlantic prawns; and the Pourtalesia jeffreysi (Arctic) and the P. wandeli

    012      |      Vol_III-0540                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    (Atlantic) species of the deep-sea urchins of the genus which is so richly

    represented in the deeper layers of the Atlantic Ocean. Confronted by such

    evidence, most zoologists now agree that the Atlantic influence on the benthonic

    fauna of adjacent arctic waters is predominant and indisputable.

            Data added during recent decades to earlier finds have been recorded in

    charts for the study of the distribution of benthonic zooplankton in northern

    waters. With the aid of these we have been able to trace much of the history of

    the arctic bottom fauna without having recourse to reasoning from more or less

    hypothetical geological changes. Presumably the features of the arctic seas were,

    in the main, during the last geological periods as they are today. On the other

    hand, ocean currents have oscillated to some degree in intensity if not in their

    course, possibly on account of slight sinking or rising of the earth crust as,

    for example, in the environs of Bering Strait.

            Several species of the Arctic are doubtless of Atlantic origin. Geographically

    these species constitute a characteristic group, usually referred to as “Eastern

    Arctic,” or, by Elkman, “Atlantic-Arctic” species. The distribution of the

    sea star of the shallower depths, the Icasterias panopla, provides a characteristic

    picture of this group (see Fig. 2). It would seem that this species (and accord–

    ingly the monotypic genus) had its origin near the borders of the Atlantic drift,

    since it flourishes most abundantly around Spitsbergen and in the Barents Sea,

    less numerously in the Kara Sea, with its easternmost advanced guards about the

    Taimyr Peninsula. On the other hand, the species was apparently able to traverse

    the waters between Spitsbergen and Greenland whence it spread along the eastern

    and western coasts of Greenland and northward to Baffin Bay. The gap in the

    distribution along the southern coasts of Greenland was probably bridged during

    a period when the temperature was lower than it is today.



    013      |      Vol_III-0541                                                                                                                  
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            A similar distribution has been shown in the hydroid species, Lafoëina

    maxima , which has been able to penetrate eastward to the New Siberian Islands

    but has not as yet been located in the waters of Novaya Zemlya (see Fig. 3).

    The arctic shrimp, Sclerocrangon ferox , found at a slightly deeper layer, is

    another example of such distribution (see Fig 4). In the Norwegian Sea this

    species is also found at the southern border of the cold area, along the con–

    tinental shelf. Apparently it is more eurybathic than the former ones above

    mentioned, for it has also been found in the upper parts of the deep sea. The

    continuous habitat of S. ferox seems to end the western side of Taimyr

    Peninsula. However, a stray community found north of the New Siberian Islands

    indicates a probable continuous occurrence in deeper layers along the slopes to

    the very limit of the habitat of eastern arctic species.

            Occasionally met with in Atlantic-boreal waters are arctic species of

    eurythermal characteristics. For example, the pycnogonid, Aeginina longicornis,

    has been found as far south as Cape Cod on the American coast and in the Skagerrak

    at the southernmost point of Norway. In the high-arctic it occurs as far east as

    the Taimyr Peninsula.

            Early in the history of the explorations of Greenland waters, zoologists

    discovered in the bottom fauna species having no occurrence at Spitsbergen or

    in the Murman or Barents seas. Later, these same species were found to occur

    occasionally in the sounds of the Arctic Archipelago as well as about Bering

    Strait and in the northernmost parts of the Pacific Ocean. These elements

    of the benthonic world of the Arctic are sometimes, therefore, referred to as

    “Western Arctic” species and, by Ekman, “Northwest-Pacific-Arctic” species.

            If we compare these distribution data with charts of ocean currents, light

    is thrown not only upon the causes of such distribution but upon the possible

    014      |      Vol_III-0542                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    origin of these species. The invasion of the polar seas was no doubt through

    Bering Strait. At their weakly vagile stages they would not able to force

    their way west through the Siberian shelf sea, only species with actively vagile

    benthonic periods of development or adults capable of crawling along the ocean

    bottom being able to advance in this direction. On the other hand, eastward

    through the shelf waters of the Beaufort Sea and the Arctic Archipelago and

    along to Greenland waters, advance is favored by the currents which block advance

    from the other direction.

            Well-known western arctic species do exist; but the charts almost always

    show a gap between Bering Strait and the Canadian Arctic Islands. This may

    merely be on account of the incomplete investigation of the fauna of the Beaufort

    Sea (the coldest part of the Arctic Sea) as well as on account of the narrowness

    of the shelf sea along these coasts. Data from the sounds between the islands

    of the Arctic Archipelago are almost equally scanty for the latter reason.

            However, if on the basis of present available data we analyze the distribu–

    tion of a species such as the arctic shrimp, ( Nectocrangon lar , which shows an

    extensive occurrence in boreal and northern Pacific waters bordering on the

    Arctic and a rather common occurrence in Greenland waters and along the coasts

    of Labrador and Newfoundland, it becomes likely that, upon closer investigation,

    the species will be found to occur more or less sporadically all along the arctic

    coast of North America (see Fig. 5). The same is true of the hydromedusa,

    Catablema multicirrata , and the scyphomedusa, Aurellia limbata , both of which

    are resticted to rather shallow waters by their polyp stages of development; of

    the ascidian, Boltenia ovifera ; and of the shrimp, Spirontocaris groenlandica ,

    which, like Nectocrangon lar, penetrates a little farther into boreal regions.

    (See Figs. 6, 7, and 8.)



    015      |      Vol_III-0543                                                                                                                  
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            These examples, selected at random, differ inter se in that two

    coelenterates, Catablem e a multicirrata and Aurellia limbata , have not been found

    in East Greenland waters but only along the western coast. This can be corre–

    lated to the fact that at their polyp stage of development they seem to be

    restricted to shallow and sheltered localities, such localities being found in

    the Arctic Archipelago and not along the slopes of the shelf sea or the exposed

    coasts of northernmost Greenland. The more eurybathic species such as the ascidian

    or the shrimps can, on the other hand, make their way along the northernmost coasts

    and into East Greenland waters, but have apparently been unable to cross the polar

    currents and so reach the shelf waters of Spitsbergen.

            That Greenland waters harbor both eastern and western arctic species becomes

    evident from the accounts here given of the eastern and western arctic components

    of the benthonic fauna of the shelf sea and adjacent upper layers — the inter–

    mediate or archibenthal layers — of the deep sea. This rich fauna is further

    enriche s d by a strong admixture of Atlantic-boreal elements and occasional rein–

    forcements from the Atlantic deep sea. Along the western Greenland coast,

    especially on the coastal banks, this richness of the fauna is notable, but

    becomes poor in the straits and sounds west of Davis Strait and Baffin Bay, at

    least, according to present data.

            We have found, then, that the eastern arctic species have little potentiality

    of invading the circumpolar regions, this being possible only to benthonic species

    having at most weakly vagile larval or polyp stages of development. In western

    arctic species, however, invasion of the circumpolar regions would seem to be

    possible. When the species is so eurybathic that it can live and propagate in

    border layers of the cold area along the submarine ridge from Greenland to

    Scotland, there is the possibility that the species can gradually invade high-arctic

    016      |      Vol_III-0544                                                                                                                  
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    regions through the mutability of the border layers.

            Several high-arctic species have doubtlessly developed from primarily

    western arctic forms. It is of speculative interest to try to trace their

    origin. Taking as an example the brittle star, Ophiura (Stegophiura) nodosa,

    we find an abundance in the Bering Sea, and the scattered finds at Sakhalin

    and Sitka seem to indicate that the species originated in Arctic-Pacific waters

    (see Fig. 9).

            Comparing the distribution of Ophiura (Stegophiura) nodosa with that of the

    lamellibranchiate, Portlandia (Yoldia) arctica , we find that Bering Strait

    represents a barrier to the latter. According to the quaternary finds, this

    strait has always prevented any expansion of habitat into Pacific waters on the

    part of this species. Whereas O. (S.) nodosa and other species with similar

    distribution have in all probability invaded the polar sea through Bering Strait,

    P. (Y.) arctica evidently had its origins in the polar sea and, although it has

    not been able to pass through Bering Strait, it has shifted its southern limit in

    European waters according to fluctuating hydrographical conditions, requiring as

    it does the isothern of - + 2.5°C. in bottom mud. The P. (Y.) arctica lived, it has

    been shown, during the last glacial period along the southern coasts of Scandinavia,

    whereas its southern limits at the present time are at Spitsbergen and at the

    entrance to the Kara Sea, with an isolated community in the White Sea (see Fig. 10).

            The amphipod crustacean, ( Stegocephalopsis ampulla , furnishes another interest–

    ing example of a typically circumpolar species of high-arctic origin. If we are

    to judge by present data, the species is scarce in its occurrence and extremely

    stenothermal in character (see Fig. 11). That it has never been found except at

    temperatures at or below -0.1°C. leads us to conjecture that it may have a more

    common occurrence along the slopes of the polar central basin in the deeper parts

    017      |      Vol_III-0545                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    of the shelf sea which are areas as yet comparatively unexplored. Invasion

    from the Atlantic or Pacific in the past is improbable, its nearest related

    species being an insufficiently described one found in the abyssal region of

    the Indian Ocean which has been placed in the same genus, but with a query.

            Before concluding, it may mall be well to recapitulate what is meant by

    the “arctic deep-sea region.” It comprises the central, or polar basin, and

    the adjacent deeps of the Norwegian Sea, Baffin Bay, and the Sea of Okhotsk.

    The shallower of shelf-sea region of the arctic seas may be said to be one con–

    tinuous region, in spite of Bering Strait which almost cuts off from the central

    polar sea the northernmost waters of the Pacific Ocean and the adjacent Sea of

    Okhotsk.

            In the benthonic fauna of the shelf region, there are remarkable differences

    between the northern Atlantic and northern Pacific waters, where the arctic-boreal

    species play a great part in the composition of the animal world. The admixture

    of typically Pacific elements is more apparent in the Okhotsk than in Bering Sea.

    In fact, the Sea of Okhotsk is the most aberrant part of the arctic seas. But

    quite apart from this, the shelf sea, even of the central arctic region, discloses

    a far more varied fauna than does the deep sea, the reasons for which we have

    already mentioned. Many of these differences may be only apparent, not real, and

    will disappear with more extensive field work along the American coasts.

            However, a close study of circumpolar species and a comparison with boreal

    species indicated that the “white spots” on the distribution charts may not be

    solely the result of inadequate investigation. In many cases the conditions of

    life in the high-arctic waters have reduced in recent times the members of species

    both in Siberian and American waters, and hydrographical changes may have set up

    barriers between the boreal-arctic species of the Pacific and Atlantic oceans.

    018      |      Vol_III-0546                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna

    We have reason to believe that temperatures of the shelf sea in earlier times

    were higher than they are today. The supposition is strengthened by the occur–

    rence of relict populations as, for example, the communities of the mussel,

    Mytilus edulis, found at the entrance to the Kara Sea, widely separated from

    the usual habitat of the species, which has its easternmost limit on the eastern

    coast of Norway bordering the Barents Sea. This warmer, Postglacial period when

    the Mytilus edulis occurred in the region of Spitsbergen dates back to 2500 to

    4000 years ago.

            On the other hand, as stated above, the occurrence of such species as the

    Portlandia (Yoldia) arctica in the White Sea would lead to the inference that

    high-arctic conditions once prevailed in what are in present times boreal-arctic

    regions.



    019      |      Vol_III-0547                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna


    BIBLIOGRAPHY

    1. Appelőf, A. “Die Decapoden Crustaceen,” Bergens Mus. Meeresfauna

    vol.2-3, 1906.

    2. ----. “Invertebrate bottom fauna of the Norwegian Sea and North

    Atlantic,” Murray, John, and Hort, J. The Depths of

    the Ocean . London, Macmillan, 1912.

    3. Berg, L.S. “Die bipolar Verbreitung der Organismen und die Eiszeit,”

    Zoogeografica vol.1, 1933.

    4. ----. “Uber die amphiboreale (diskontinuierliche) Verbreitung der

    Meeresfauna in der nőrdlichen Hemisphäre,”

    Zoogeografica vol.2, 1934.

    5. Berthelsen, E. “Contributions to the animal ecology of the fjords of

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    Medd. Grø n land vol.108, no.3,1937.

    6. Birulia, L. “Beiträge zur Kenntnis der Decapoden-Krebse der eurasiatischen

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    7. Borg, F. “Uber die geographische Verbreitung der innerhalb des

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    Archiv für Naturgesch . Vol.2, 1933.

    8. G B reitfuss, L. “Die biologischen Problems der Arktis,” Arktis

    l. Jahrg., H.3/4, pp.97-112, 1928.

    9. Broch, Hjalmar. “Anthozoa, mainly from Pacific waters, collected by

    U.S.S.R. expeditions 1930-1932,” Leningrad. Gosudarst–

    vennyi Gidrol.Inst. Issled.Morei S S . SR vol.23, 1940.

    (Russian and English.)

    10. ----. “Cirripedia thoracica von Norwegian und dem norwegischen Nordmeer,”

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    11. ----. “Einige Probleme der giogeographischen Abgrenzung der artischen

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    12. ----. “Grősse der Meerestiere und Temperatur ihres Lebensraumes,”

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    13. ----. “Noen dyregeografiske trekk i nordhavenes bunndyreverden,”

    Norsk Geogr.Tid [ ?] skr . vol.6, 1937.

    14. ----. Oktokrallen des nőrdlichen Pazifischen Ozeans und ihre Beziehung

    zur atlantischen Fauna,” Norske Videnskaps-Akad.

    Mat.-Nat.Kl. Skrifter , 1935.



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    15. ----. “Post-glacial interchange between Pacific and Atlantic deeper

    living boreal fauna!” Norsk Geogr.Tidsskr . vol.12, 1949.

    16. Brotskaia, V.A. and Zenkevich, L.A. “Kolichestvennti Uchet donnoi

    Fauny Berentsova Moria” (Quantitative evaluation of the

    bottom fauna of the Barents Sea.) Vaesoiuznyi Nauch. Issled.

    Inst.Rybnogo Khoz.Okeanogr., Moscow. Trudy vol.4, 1939.

    (Russian with English r e é sum e é .)

    17. ----, and Zenkevich, L.A. “Materialy po kolichestvennomu nchetu donnoi

    fauny Barentsova, Belogo i Karskogo morei. 6. Kolichestvennyi

    uchet donnoi fauny Cheschoi guby.” (Materials for the quan–

    titative evaluation of the bottom fauna of the Barents, White

    and Kara Seas. 6. A quantitative evaluation of the bottom

    fauna of the Cheshskaia Bay.), Gosudarstvennyi Okeanogr.

    Inst.,Moscow. Trudy vol.2, no.2, pp.41-57, 1932. (Russian

    with English summary.)

    18. Carlgren, Oskar. “Die Brutpflege der Actiniarien,” Biologisches

    Zentralbl. Vol.21, 1928.

    19. ----. “Ceriantharier, Zoantharier och Actiniarier,” Medd.Grønland,

    Suppl. Vol.23, no.24, 1928.

    20. Carpenter, W.B. “Preliminary report of dredging operations in the sea

    to the north of the British Islands in H.M.S. ‘Lightening,’”

    Roy.Soc.Lond. Proc . Vol.17, 1869.

    21. Dall, W.H. “On climatic conditions at H N ome, Alaska, during the Pliocene,”

    Amer.J.Sci . vol.23, 1907.

    22. ----. “Summary of the marine shellbearing mollusks of the NWcoast of

    America from San Diego to the Polar Sea.” U.S.Nat.Mus. Bull .

    no.112, 1921.

    23. Deriugin, K.M. “Fauna belogo moria i usloviia ee sushchestvovaniia.”

    (Fauna des weisen Meeres und ihre Existenzbedingungen.),

    Leningrad. Gosudarstvennyi Gidrol.Inst. Issled.Morei SSSR

    no. 7/8, 1928. (Russian with German r e é sum e é .)

    24. Gorbunov, G.P. “Fauna Crustacea-Decapoda Severnoi Poloviny Karskogo

    Moria,” (The Decapod crustacea of the northern half of the

    Kara Sea.), Leningrad. Arkticheskii Nauchn-Issled.Inst.

    Trudy vol.9, pp.59-77, 1934.

    25. ----. “Materialy no faune Decapoda Zemli Frantsa-Iosifa.” (Material

    on the Decapod fauna of Franz Joseph Land.), Ibid , vol.2,

    pp.80-91, 1932. (Russian with German r e é sum e é .)

    26. Gurianova, Ev. “On the question of the composition and origin of the

    fauna of the polar basin bassalia,” Akad.Nauk. Comptes Rendus

    ( Doklady ) vol.20, no.4, 1938. (In English.)



    021      |      Vol_III-0549                                                                                                                  
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    27. ----. “Zoogeograficheskii ocherk fauny Isopoda arktiki.” (Zoogeographi–

    cal study of the arctic Isopods .), Arctica no.2, pp.127-52,

    1934. (Russian with English resum e é .)

    28. ----. “Zur Zoogeographie der Crustacea-Malacostraca des Arktischen

    Gebietes,” Zoogragrafica vol.2, 1936.

    29. Hartmeyer, R. “Studien an westgrőnlőndischen Ascidien,” Medd.Grønland

    vol.62, pp.1-37, 1923.

    30. Idelson, M.S. “Materialy po kolichestvennomu uchetu donnoi fauny

    Barentsova, Belogo i Karskogo Morei,” (Materials for the

    quantitative evaluation of the bottom fauna of the Barents,

    White and Kara Seas. No.7. Distribu g t ion of the benthos

    biomass in the southern Barents Sea. The influence of different

    factors in the density of the sea bottom population.),

    Gosudarstvennyi Okeanogr.Inst. G Trudy vol.3, 1934.

    (Russian with English resum e é .)

    31. Jensen, Ad.S. “Two new West Greenland localities for deposits from the

    Ice Age and the postglacial warm period,” Danske Vidensk.

    Selsk. Biologiske Medd . Vol.17, 1942.

    32. Jungersen, H.F.E. “Alcyonaria, Antipatharia og Madreporaria,” Medd .

    Grønland vol.23, no.13, 1915.

    33. ----. “Fra Ingolf-Expeditionen. Bemaerkninger om Dybhavsfaunaen og

    dens Fordeling i de nordlige Have,” Geogr.Tidsskr . vol.14, 1898.

    34. Kramp, P.L. “Hydroids collected in West-Greenland Fjords in 1911 and

    1912,” Medd.Grønland vol.91, no.3, 1932.

    35. Kűkenthal, W. “Die marine Tierwelt des arktischen und antarktischen

    Gebietes in ihren gegenseitigen Beziehungen,” Berlin. Univ.

    Inst.fűr Meeresk. Verőff . Vol.11, 1907.

    36. Molander, A.R. “Northern and arctic invertebrates in the collection of

    the Swedish State Museum. VII. Alcyonacea, Svenska Vetenskapsa–

    kad. Handl . n.s., ser.4, vol.51, 1915.

    37. Murray, John, and Hjort, J. The Depths of the Oceans . London, Macmillan,

    1912.

    38. Nordgaard, O. “Bryozoa from the arctic regions,” Tromsø/ Mus. Aarsh.

    vol.40, 1918.

    39. Popov, A.M. “Hydrobiological explorations in the Nordenskiőld Sea,”

    Internationale Rev.der Gesamt.Hydrobiol.u.Hydrogr . vol.25,

    1931.



    022      |      Vol_III-0550                                                                                                                  
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    40. Retovskii, L.O. “Fauna Crustaces-Decapoda Sibirskikh Morei.”

    (Crustacean-Decapod fauna of the Siberian arctic.), Leningrad.

    Arkticheskii Nauchn-Issled.Inst. Trudy vol.33, pp.7-29, 1936.

    (Russian with German resum e é .)

    41. Rylov, V.M. “Alcyonaceae, sofrannye ekspeditsiei plovuchego Morskogo

    Nauchnogo Instituta v 1921 g.) (Alcyonaceae, gesamelt von

    der Expedition des Schwimmenden Wissenschaftlichen Meeresinstitut

    im Jahre 1921.), Morskoi Nauch.Inst., Moscow. Trudy vol.2,

    pt.1, pp.61-78, 1926.

    42. ----. “Hydroidea-Athecata, sofrannye ekspeditsiei Instituta v 1921 g.”

    (Hydroidea-Athecata, aus den Sammlungen der Expedition den

    Institus im Jahre 1921.), Plovuchii Morsk.Nauch.Inst.,

    Moscow. Trudy vol.9, 1924. (Russian with German resum e é .)

    43. ----. “Hydroidea in Alcyonaria, sofrannye v Barentsovom More Murmanskoi

    Biologicheskoi Stansiei vo vremia reisov po kolskomu meridianu

    v 1921 g.” (Hydroidea et Alcyonaria, collectionn e é s dans la mer

    de Barenz par la Station Biologique du Mourman pendant les

    cr o ô is e é es le long du m e é ridien de Kola en 1921.), Akad.Nauk.Zool.

    Muz. Ezhegodnik vol.27, pt.2/3, pp.233-46, 1927. (Russian with

    French resum e é .)

    44. Sars, G.O. Mollusca Regionis Arcticae Norvegiae. Christiania , 1878.

    45. Schellenberg, A. “Die Gammariden Spitzbergen” Berlin.Univ.Zool.Muz.

    Mitt . Vol.11, 1924.

    46. Shorygin, A.A. “Iglokzhie Barentsova Moria.” (Die Echinodermen des

    Barentsmeeres.), Morskoi Nauch.Inst.Moscow. Trudy vol.3, no.4,

    1928. (Russian with German resum e é .)

    4 6 7 ----. “Iglokzhie Belogo Moria.” (Die Echinodermen des Weissen Meeres.),

    Morskoi Nauch.Inst., Moscow. Trudy vol.2, no.1, pp.3-59, 1926.

    (Russian with German resum e é .)

    48. ----. “Iglokzhie, sofrannye ekspeditsiiami Plovuchego Morskogo Nauchnogo

    Instituta v 1921, 1923 i 1924 godakh.” (Echinod ermata aus den

    Sammlungen der Expeditionen des Wissenschaftlichen Meeresinstitus

    im Jahre 1921, 1923 und 1924.), Plovuchii Morsk.Nauch.Inst.,

    Moscow. Trudy vol8, 1925. (Russian with German resum e é .)

    49. Sivertsen, E. “Crustacea Decapoda, Euphausiacea and Mysidacea of the

    Norwegian expeditions to East Greenland (1929-1932),” Norsk

    Polarinstitutt. Skrifter no.66, 1935.

    50. Spärck. R “Contributions to the animal ecology of the Franz Joseph

    Fjord and adjacent East Greenland waters. I-II,” Medd. Grønland

    vol.100, no.1, 1933.



    023      |      Vol_III-0551                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna - Bibliography

    51. Stephensen, K. “Grønlands Krebadyr og Pycnogonider,” Ibid . vol.22,

    no.1, 1913.

    52. ----. “The Scoresby Sound Committees 2nd East Greenland Expedition to

    King Christian IX’s Land. Crustacea and Pycnogonida,” Ibid .

    vol.104, no.15, 1933.

    53. ----. “Zoogegraphical investigations in certain fjords in Southern

    Greenland with specific reference to Crustacea, Pycnogonida

    and Echinodermata,” Ibid . vol.53, no.3, 1916.

    54. Strelnikov, I.D. “La faune de la mer de Kara et ses conditions

    ecologiques,” Acad.Sci. Comptes Rendus vol.188, 1929.

    55. Theel, Hj. “Northern and arctic invertebrates in the collection of the

    Swedish State Museum. II. Priapulids, Echiurids, etc.,”

    Svenska Vetenskapsakad. Handl . n.s., ser.4, vol.40, 1906.

    56. Thorson, Gunnar. “Contribution to the animal ecology of the Scoresby

    Souhd Fjord Complex (East Greenland),” Medd.Grønland vol.100,

    no.3, 1934.

    57. ----. “Investigations on shallow water animal communities in the

    Franz Joseph Fjord (East Greenland) and adjacent waters,”

    Ibid . vol.100, no.2, 1933.

    58. ----. “The larval development, growth, and metabolism of arctic marine

    bottom invertebrates compared with those of other seas,” Ibid .

    vol.100, no.6, 1936.

    59. Ushakov, P.V. “Materialy po gidroidam arkticheskikh morei SSSR.”

    (Materials on the hydroids of the arctic seas of U.S.S.R.),

    Leningrad, Arkticheskii Nauchn.-Issled.Inst. Trudy vol.50,

    pp.5-34, 1937. (Russian with English resum e é .)

    60. Vibe, Christian. “Preliminary investigations on shallow water animal

    communities in the Upernavik- and Thule-districts (Northwest

    Greenland),” Medd.Grønland vol.124, no.2, 1939.

    61. Winkler, M.E, and Schmitt, W.L. “Notes on crustacea chiefly Natantia,

    collected by Capt. R.A. Bartlett in arctic seas,” Wash.Acad.

    Sci. J . vol.26, 1936.

    62. Zenkevich, L.A. “Materialen zur quantitative Untersuchung der Bodenfauna

    des Barents und des Weissen Meeres,” Morskoi Nauch.Inst.,

    Moscow. Trudy vol.2, no.4, pp.56-64, 1927. (German only.)



    024      |      Vol_III-0552                                                                                                                  
    EA-Zoo. Broch: Benthonic Fauna - Bibliography

    63. ----. “Nekotorye Momenty Zoogeografii Severnogo Polarnogo Basseina

    v sviazi e voprosom o ego paleograficheskom proshlom.”

    (Beiträge zur Zoogeographie des nőrdlichen Polarbassins im

    Zusammenhang mit der Frage Über dessen palägeogfaphische

    Vergangenheit.), Zoologicheskii Zhurnal vol.12, 1933.

    (Russian with German resum e é .)

    64. ----, and Brotskaia, V.I. “Materialy po ekologii rukovodiashchikh form

    bentosa Barentsova Moria.” (Some date on the ecology of

    dominants in the bentos of the Barents-Sea.), Moscow, Univ.

    Uchenye Zap.Wiss.Ber . vol.13, pp.203-26, 1937. (Russian with

    English resum e é .)

           

    Hjalmar Broch

    Plankton of Arctic and Subarctic Seas


    Unpaginated      |      Vol_III-0553                                                                                                                  
    EA-Zoology

    (M . ax J. Dunbar)


    PLANKTON OF ARCTIC AND SUBARCTIC SEAS

           

    CONTENTS

    Page
    Chordata 7
    Enchinodermata 8
    Chaetognatha 8
    Mollusca 9
    Crustacea 9
    Annelida 13
    Coelenterata 13
    Protozoa 16
    Distribution 16
    Bibliography 21



    001      |      Vol_III-0554                                                                                                                  
    EA- [ ?] Zoology

    (M. J. Dunbar)


           

    PLANKTON OF ARCTIC AND SUBARCTIC SEAS

            The more productive part of the northern regions is the sea, not the

    land. The economy of the Eskimo, even in districts rich with commercially

    valuable fur, is based upon the life produced in the arctic and subarctic

    waters.

            Production in the sea is not easy to measure. There are as yet few

    estimates of the bulk or weight of living matter produced in unit volumes of

    different types of sea water, and in all cases the possible error may well be

    considerable. There has as yet been no estimate of production in arctic water,

    the most northerly being that of Kreps and Verzhbinskaia (28) in the Barents

    Sea. The summary of estimates of production published by Riley (32), however,

    shows higher figures for the more northern parts of the Temperate Zone than

    for the tropical regions. It has long been supposed on purely cursory evidence

    that his was so, but we have not yet reached the stage where we can establish

    it with certainty. In making the production estimates, much depends on the

    proper evaluation of such factors as speed of population turnover (from brood

    to brood), the depth of the euphotic zone (the light zone in which plant cells

    can grow and divide), the speed of loss of plant cells by sinking from the

    surface layers, and the variation in production, in any given area, throughout

    the year.



    002      |      Vol_III-0555                                                                                                                  
    EA- PB. Zoo. Dunbar. Plankton

            The basic life in the sea, as on the land, is the plant production, the

    bulk of which is planktonic (phytoplankton), the word “plankton” being an

    inclusive term for all the forms of life, both plant and animal, which cannot

    swim fast enough to be independent (insofar as locomotion is concerned) of the

    ocean currents, and which are therefore carried with them. Thus the pelagic,

    or free-swimming larval stages of benthonic animals make up an important part

    of the marine plankton, the so-called “temporary” plankton, present in the

    plankton only at specific stages of their life cycles and specific times of

    year. Most of the zooplankton, however, consists of animals whose whole lives

    are spent plantonically.

            Arctic water and the arctic climate have several characteristic favorable

    to the growth of phytoplankton, compared to tropical or subtropical water. The

    low temperatures allow high concentrations of dissolved gases, both carbon dioxide

    for photosynthesis and oxygen for energy requirements; the long summer days allow

    photosynthesis to continue for longer periods (during the summer season) than in

    regions closer to the equator; and it is probable that the greater viscosity of

    the cold water has an important effect on the flotation of the plant cells, so

    that the period of their sojourn in the ouphotic zone is extended, when com–

    pared with warmer regions, despite the fact that the euphotic zone in equatorial

    regions is considerably deeper than toward the poles, for obvious reasons.

            Another characteristic of polar water which appears to encourage phyto–

    plankton growth and division, following certain recent experimental studies,

    is the quantity of melting ice normally present during the arctic summer. Water

    resulting from the recent melting of ice is rich in the trihydrol molecule.

    (H 2 O)3, a polymer of water. Such water has been shown to stimulate the growth

    and multiplication of plant cells used experimentally ( Euglena , Spirogyra ,

    003      |      Vol_III-0556                                                                                                                  
    EA-Zoo. Dunbar. Plankton

    Nitzschia ) (1; 2; 3; 18).

            Brandt (6) suggested that the productivity of the colder water of the

    ocean might in part be due to the reduction of the activity of the denitrifying

    bacteria (which reduce salts containing nitrogen to free gaseous nitrogen) in

    water of low temperature. This has not been supported by later work (19, p.113),

    which has derogated the importance of these bacteria in the metabolism of the sea.

            It has been suggested that the great numbers of sea birds which breed in

    the North provide a constant supply of nutrient salts, or fertilizers, during

    the whole of the summer. This effect is circular, since the numbers of the

    birds depen t d ultimately on the food supplied by the sea; but there is little

    doubt that the fertilizing effect of sea birds is important. In regions par–

    ticularly rich in colonies of birds (kittiwake, murre, dovekie, etc.), such as

    the interior of Disko Bay in West Greenland, the phytoplankton production is

    most remarkably high, so high as to be immediately apparent at sight, and so

    that plankton nets used in those waters are soon clogged completely and become

    useless. Moreover, the phytoplankton in such areas does not appear to show the

    normal spring and autumn peaks of production, but to continue at maximum pro–

    duction all summer long. These effects are apparent also in the water surround–

    ing isolated bird colonies, in otherwise normal water areas.

            Against these characteristics, it is necessary to put two properties which

    operate in the opposite direction. The shallower euphotic zone has already been

    mentioned; it has the effect of conc d e nitrating the phytoplankton, and consequently

    some of the zooplankton, [ ?] into a shallower vertical range than is found in

    tropical waters, since the vertical range of possible plant growth is restricted.

    Also, the low temperatures (an asset in the matter dissolved gases) have the

    effect of reducing growth rates, so that the intervals between breeding periods

    004      |      Vol_III-0557                                                                                                                  
    EA-Zoo. Dunbar. Plankton

    In the plankton are longer than in warmer water; the population turnover must

    be supposed to be slower, and the mortality rate per brood perhaps higher,

    than elsewhere.

            The growth-rate effect has resulted, in those planktonic animals so far

    studied, in the establishment of a type of breeding cycle which may be peculiar

    to cold-water regions. In Sagitta elegans arctica , Themisto libellula , and two

    species of Thysanoessa , an alternating, or two-phase, breeding cycle was found

    in which two independent broods, separated in age by half a year or by one year

    (according to species), exist side by side, neither being parental to the other.

    During the breeding season, three separate size groups are present; the breeding

    group, the newly developed young, and the intermediate adolescent group (12; 7;

    13). Size frequencies of this sort, with the implied two-phase breeding cycle,

    have also been recorded in Anonyx nugax from East Greenland (38), and in

    Euphausia superba in the Antarctic waters (35). Such breeding cycles have the

    effect of offsetting the check on population resulting from slow growth rates

    in cold water. They have the interesting corollary that the two broods present

    at any one time are genetically separate, and unless the system goes out of

    phase in one way or another, the conditions are presumably favorable for the

    development of differences between the broods which might in time lead to

    speciation.

            If this analysis of the productivity of arctic water is correct, areas

    in which arctic water mixes with more temperate water should be especially

    productive, for in such regions the inhibiting factors of slow growth rates

    should be removed. Such regions do in fact appear to be remarkably productive

    of life; for it is precisely in the mixing areas that the great commercial

    fishers are developed, as on the banks of Nova Scotia, Newfoundland, and

    005      |      Vol_III-0558                                                                                                                  
    EA-Zoo. Dunbar. Plankton

    West Greenland, off rhe coasts of Iceland and of Norway, and in the North Sea.

    Estimates of plankton production in these regions are correspondingly high.

            Without as yet going into detailed definition, it is to the productivity

    of the sea water that Madsen has recently directed attention for the finding

    of a working criterion for the delimitation of the arctic and subarctic zones

    in the sea (29, 30). In a study of the littoral fauna of the Arctic and Sub–

    arctic, Madsen found that the barren intertidal zone of the high-Arctic began

    and ended quite suddenly; that the littoral fauna, for instance, of South

    Greenland, characterized by certain key species, disappeared suddenly at

    Angmagasalik on the east coast and at Upernivik on the west coast. He showed

    that a purely climatic criterion would not suffice to explain this pattern,

    and suggested that the productivity of the water itself was the limiting factor

    involved (see “Littoral Fauna of the Arctic ). It has been pointed out that this

    criterion may well apply also to other parts of the marine fauna besides the

    littoral, and that the essential factor in inducing the greater productivity

    of the southern part of northern waters may be the admixture of nonarctic water;

    thus a natural and practical criterion for the delimitation of arctic from

    subarctic water becomes immediately available (10).

            The arctic marine plankton is remarkable for the size attained by the

    individual members, when compared to those of temperate or tropical waters.

    i I t is the general rule that poikilothermic inhabitants of cold water grow to

    a remarkably large size; this applied both to individuals of species with wide

    range from temperate to arctic (as the chaetognath Sagitta elegans ), and to

    the northern or cold-water species which replace tropical or temperate forms

    within any one genus (such as the copepod Calanus hyperboreus which to some

    extent replaces Calanus finmarchicus in the high-Arctic). The factors responsible

    006      |      Vol_III-0559                                                                                                                  
    EA-Zoo. Dunbar. Plankton

    for this phenomenon have not yet been fully analyzed; one important factor is

    the effect of temperature on development of the gonads. “Delayed sexual

    maturity, which favors growth in size, appears to be directly dependent on

    retardation of growth at lower temperatures, and this is a common character–

    istic of northern marine creatures” (20).

            The size effect has been studied in some detail in the field by two

    Scandinavian workers, Sømme and Jespersen. Working on the marine copepod

    Crustacea of West of East Greenland waters, Jespersen has demonstrated the

    presence of two quite separate size groups in adult Calanus finmarchicus of

    both sexes (22; 23). The same effect has been recorded in Calanus hyperboreus

    in the waters of West Greenland (23a), and in the Norwegian Sea (37). These

    differences were ascribed to the presence of a mixed population with two

    different histories, one group having developed in polar water, the other in

    boreal water, the individuals of larger body size belonging to the colder water.

    However, since the discovery that the populations of C. hyperboreus from north–

    east Greenland, clearly from polar water, correspond to the smaller size group

    of West Greenland (23), this theory must be left in abeyance. We have thus no

    plausible explanation for the size difference in this species.

            The marine plankton of the North follows the general rule that species

    are fewer in number in polar than in other areas, but are often represented

    by greater numbers of individuals. The number of species in the [ ?] northern

    plankton, nevertheless, is enormous, as would be expected in so varied an ecolo–

    gical grouping. In the following account of the species, only the more abundant

    forms are discussed and those less abundant forms which display some feature

    of special interest. Only the zooplankton is considered.



    007      |      Vol_III-0560                                                                                                                  
    EA-Zoo. Dunbar. Plankton

           

    Chordata

            Pure arctic water is not rich in fish; consequently, fish eggs and larvae

    are seldom dominant or even abundant in the plankton. Most of the fish present

    in arctic water lay demersal eggs, which do not in any event appear in the

    plankton. In subarctic regions, however, with considerable proportions of

    boreal water, the eggs of fish are very abundant as temporary plankton. Thus,

    the eggs of the Atlantic cod ( Gadus callarias ) appear in March and April in

    the subarctic waters of West Greenland, especially in the sheltered fjord

    waters where the cod spend the winter. Larval fish of many species are found

    in the plankton; even the fish which lay demersal eggs pass through a stage in

    which the young are pelagic, and since their powers of swimming are limited,

    these young fish are included in our definition of the plankton. In certain

    localized coastal areas, close to the influx of fresh water, the young of the

    Cottidae (sculpins) are sometimes present in the early summer in large numbers,

    even on occasion to the exclusion of other planktonic forms. Thus several

    hundred young specimens of the Greenland sculpin, Myoxocephalus scorpius

    groenlandicus , up to 26 millimeters in length, were taken in a single haul

    in Glasgow Inlet, Lake Harbour, in v southern Baffin Island (9). Other fishes

    frequently caught in larval stages in the plankton are Gymnocanthus tricuspis

    (sculpin); Agonus spp. And Aspidophoroides spp. (poachers and alligator fishes);

    Eumicrotremus (lumpsucker); various liparian s ; Lumpenus (eel blenny); Stichaeus

    (northern blenny). Many planktonic eggs and larvae of fishes found in both

    arctic and boreal waters are described by Ehrenbaum (14).

            The Urochordata are represented in the arctic and subarctic plankton almost

    entirely by the Larvacea; the Thaliacea and the larvae of the Ascidacea being

    008      |      Vol_III-0561                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    comparatively rare. The commonest of the Larvacea is Oikopleura , which is

    the summer is often very abundant; the house, or test, being then frequently

    seen at the surface. In the Labrador Sea and Newfoundland area, O. vanhőffeni

    has been found to be characteristic of arctic water, and O. labradoriensis more

    abundant in mixed arctic and Atlantic water (16). The genus Fritillaria is

    also fairly common.

           

    Echinodermata

            Larval stages of bottom-living animals tend to be somewhat, reduced in the

    time dimension in cold water, for reasons still unknown. Consequently various

    larvae of the echinoderms are collected in the plankton nets only during a very

    short period in the spring.

           

    Chaetognatha

            The arrowworms (or glass worms) are represented by several species, by far

    the commonest of which is Sagitta elegans arcitca , separated from the typical

    elegans form of the temperate regions by much larger size, a relatively shorter

    tail segment, and differences in the numbers of oral hooks. S. elegans arctica

    is a neritic form, and is found usually in the upper 50 to 100 meters; it is

    very common, sometimes dominating the plankton hauls in fjord waters. It is

    an exceedingly voracious creature, and will attack animals as large as itself;

    its normal diet consists of copepods. Large specimens up to at least 50 millimeters

    in length have been found, and individuals over 40 millimeters are common. Other

    chaetognaths occur only in much smaller numbers. Next in abundance to S. elegans

    is probably Eukrohnia hamata , a deepwater temperate form, found also in shallower

    water in the Subarctic. In areas with much Atlantic or Pacific admixture, more

    southerly forms are naturally found, and Atlantic species are of course common

    009      |      Vol_III-0562                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    in the Labrador Sea and in the warm layer underlying the arctic water of the

    polar basin. Such temperate or cosmopolitan species as Sagitta hexaptera ,

    S. serratodentata , and S. elegans elegans are included in this group.

           

    Mollusca

            Trochophore and veliger larvae of bottom-living mollusks are common,

    and they appear to be produced during the whole of spring and summer. In more

    temperate regions, these larvae are found in plankton during the entire year.

    The same may be true of arctic waters, but we have as yet almost no winter field

    work to go on. Of the pelagic Mollusca, two species are very abundant in arctic

    water, and are indeed so characteristic as to be used as indicators of arctic

    water in mixing areas. These are Limacina helicina , the little black “sea

    butterfly,” and Clione limacine , a larger, yellow-brown form. L. helicina is

    often present in great numbers close to the surface in the late summer and

    early fall, during which time it forms an important food of various fish, in–

    cluding the Atlantic cod in West Greenland and in Ungava Bay; the ringed seal,

    Phoca hispida, has also been found to be eating this little mollusk in

    September (11). According to unpublished information from Dr. George MacGinitie,

    from Point Barrow, Alaska, Clione has been much more abundant than Limacina in

    that area in recent years.

           

    Crustacea

            The decapods are not planktonic as adults, although prawns and shrimps are

    sometimes caught in plankton nets towing near the bottom. The larval stages,

    however, are very abundant in the plankton during the spring and early summer,

    as they are in most parts of the coastal waters of the world.

            Euphausiids . The euphausiids (order Euphausiacea) are found in deeper

    010      |      Vol_III-0563                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    water than the bulk of the coastal plankton, and in the deep oceanic water

    beyond the continental shelves. The important species ecologically are Thysanoessa

    raschill , T. inermis , and Meganyctiphanes norvegica . All three are found in

    boreal water as well as arctic water, in fact, they are more common in the

    southern parts of their ranges. Meganyctiphanes is known from the Mediterranean.

    The euphausiids form the bulk of the food of certain whales, including the blue

    whale in the North Atlantic region, and are known to whalers a [ ?] “krill.” They

    are also eaten quite extensively by the harp or saddleback seal ( Phoca groenlandica )

    and by the ringed seal ( P. hispida ), especially in subarctic areas with boreal

    waters present. In pure polar water, their place in the seal economy appears

    to be taken by the hyperiid amphipod Themisto . The same seems to be true for

    the food habits of many fishes, including various species of cod, the arctic

    char ( Salvelinus alpines ), and the capelin ( Mellotus villosus ), which commonly

    eat Thysanoessa in subarctic waters.

            Mysids . Mysids (order Mysidacea), on the continental shelf, keep close to

    the bottom as a rule; but they are frequently caught in plankton nets and are

    normally included in the planktonic fauna. In coastal waters the commonest

    species is Mysis oculata , which occupies approximately the same ecological

    position, at least in the food chain, as does Thysanoessa . It is not uncommon

    to find Mysis oculata swarming in shallow water in the neighborhood of freshwater

    influxes, close to the surface. It is an arctic circumpolar littoral species,

    often taken in the stomachs of seals and fish. It is also found as an arctic

    relict in the Baltic Sea. Mysis ( Mictheimysis ) mixta is much less abundant,

    but fairly common, and is not as strictly arctic as oculata . In deeper water

    (usually below 100 meters in the daytime), two species of Boreomysis , among the

    largest mysids known, are common in northern waters: B. arctica being a subarctic

    010a      |      Vol_III-0564                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    form, which is replaced by S B . nobilis as the boreal influence from the south

    becomes weaker.

            Amphipods . The amphipods (order Amphipoda) are both plentiful and varied

    in the arctic plankton, sometimes dominating the planktonic scene. One of the

    most successful and widespread crustacean orders, they function as scavengers

    in many animal communities. Although they there are many more littoral and benthonic

    spcies than planktonic, they have nevertheless invaded the water layers with

    typical success. In the planktonic habitat the suborder Hyperiidea are the

    dominant amphiods, and have become more completely planktonic in habit than

    either the Gammaridea (the largest amphipod group) or the more rare and aberrant

    Caprellidea; they are less typically scavengers. The large, dark-purple Themisto

    libellula is the commonest of these planktonic hyperiids, and perhaps one of

    the most important forms in the whole of the Arctic, in any habitat, terrestrial

    or aquatic. It appears to replace in many ways of the euphausiids in arctic water,

    and is a key species between the smaller planktonic Crustacea (especially the

    copepods) and the fish and sea mammals (13). In Canadian eastern arctic waters,

    and probably over the whole Arctic, it is the most important single food item

    of the ringed seal, and is also eaten in quantities by the arctic char. But

    essentially an animal of polar water, it is much less abundant in the subarctic

    mixed-water region. It is often found at the surface of the water in the

    brightest of sunshine, which is rare among planktonic animals and which is

    perhaps made possible by the dark pigmentation; in general it seems to have

    a vertical optimum noticeably higher in the water than the rest of the zoo–

    plankton. Its food consists largely of copepods and detritus. MacGinitie

    ( in litt. ) describes Themisto libellula as being washed up on the beach in

    summer at Point Barrow in great abundance.



    011      |      Vol_III-0565                                                                                                                  
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            Other common hyperiids of the arctic and subarctic are Hyperia galba ,

    H. medusarum , and Hyperoche medusarum . All three are normally found in

    somewhat deeper water than Themisto libellula , and they are also of wider

    distribution horizontally, being found in the North Atlantic and North Pacific

    as well as in polar water.

            Of the gammarid amphipods, the commonest in the coastal waters of the

    North are Pseudalibrotus littoralis and Gammarus locusta. G. locusta is

    essentially a littoral animal, but it is frequently caught in plankton nets

    in fjords and along the coast; it is widely distributed in arctic and northern

    temperate regions. Pseudalibrotus littoralis , on the other hand, is almost

    confined to arctic water, and in the subarctic belt is normally found only in

    the neighborhood of freshwater influxes, close into shore. It has been found

    to be the commonest food of the arctic char ( Salvelinus alpinus ) in Frobisher

    Bay, Baffin Island, during the months of July and August (E. H. Grainger,

    unpublished data). Two common pelagic arctic species are Pseudalibrotus

    glacialis and P. nanseni , both restricted to arctic water.

            Anonyx nugax is another very common gammarid amphipod of arctic and

    boreal seas, found most abundantly in inshore waters. So many gammarids are

    normally found in northern seas that it is impracticable to mention them all

    in this arcticle; among the more common genera are Acanthonotosoma , Westwoodilla ,

    Calliopius , Apherusa , Pontogeneia , Pleustes , Gammaracanthus , and Ischyrocerus .

            The caprellid amphipods are represented in arctic and subarctic waters by

    the common little “ghost shrimp,” Caprella septentrionalis , present both on

    the seaweeds of the littoral and in the water above them.

            Cirripeds . The cirriped Crustacea (barnacles) are sessile forms, but the

    larvae, both nauplius and cypris stages, are numerous in the epiplankton during

    012      |      Vol_III-0566                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    the early part of the spring-summer season. Balanus balanoides is the most

    common species.

            Copepods . At most times of year, the copepod Crustaces (order Copepoda)

    are dominant in the plankton. In subarctic waters, Calanus finmarchicus

    is the most abundant form, replaced to a large degree in pure arctic water

    by Calanus hyperboreus , a larger species which may grow up to one centimeter

    in length. It is a remarkable fact that Calanus hyperboreus has not been

    recorded from Hudson Bay (39); it is, however, scarcely credible that future

    and more extensive plankton towing will not show it to be common there. In

    deep water (generally below 50 meters in arctic water, much deeper in more

    southern regions), Metridia longa often dominates. This species is definitely

    arctic in its affinities, and has been found dead in large quantities near

    the surface in warmer water (22). Other common copepods in northern regions

    are Oithona similis (Pacific, Atlantic, and arctic water); Acartia clause

    (Atlantic , and Pacific, and recorded from James Bay and southern Labrador,

    but not from East or West Greenland - a most remarkable distribution);

    A. longiremus (circumpolar arctic and subarctic); Pleuromamma robusta

    (Atlantic boreal,) as far north as Davis Strait); Undinella oblonga (arctic,

    less common, carried by undercurrents into the Atlantic); Pareuchaeta glacialis

    (arctic predominantly); P. norvegica (Atlantic boreal, mainly in subarctic

    waters in our range); Gaidius tenuispinus and G. brevispinus Pacific, Atlantic,

    and arctic); Microcalanus pygamaeus (arctic form, spreading down also in

    Atlantic and pacific boreal waters, usually in deep water); Pseudocalanus

    minutes [ ?] (Pacific and Atlantic). The last-named species, which now

    includes the form known formerly as P. elongatus , is very abundant, a small

    species, and sometimes dominant in the plankton.



    013      |      Vol_III-0567                                                                                                                  
    EA-Zoo. Dunbar; Plankton

            The copepods are of vital importance in the biology of the sea. They

    are the chief link in the food net between the phytoplankton and the larger

    animal plankton and nekton. To a large extent they feed on diatoms, and

    they are themselves the food of many pelagic fish as well as of the right

    whales. At times they are so abundant at the surface as to color the whole

    area pink or reddish, such swarms consisting usually of Calanus .

            Ostracods . The Ostracoda do not form any significant proportion of the

    northern plankton. They are sometimes fairly common at the surface, but as

    a rule are deepwater forms. The commonest species is Conchoecia superb .

            Branchiopods . Of the Branchi o poda, the great majority of which are

    freshwater animals, the only group represented in the marine plankton is the

    suborder Cladocera, and even in that group there are few marine species. They

    appear occasionally in considerable numbers in the surface layers during the

    months of July and August.

           

    Annelida

            Some of the annelid worms are occasionally caught pelagically as adults,

    but in the northern regions there are no annelids whose normal adult habitat

    is the free water.

           

    Coelenterata

            The a A nthomedusae and Leptomedusae, both of which groups have well-developed

    hydroid stages, appear in the plankton only during the spring and summer

    months, usually between May and September in the Arctic and Subarctic. The

    Trachymedusae, Narcomedusae, and Scyphomedusae, in which the pol y p stage is

    much reduced or suppressed, are found during most of the y year, as also are

    the Siphonophora and the Ctenophora. It is possible, however, that these

    014      |      Vol_III-0568                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    nonhydroid groups pass at least part of the winter in resting stages, for in

    the experience of the writer they are very scarce during the months of Decem–

    ber to March in West Greenland. There has been almost no work done hitherto

    on the winter distribution and condition of the arctic plankton.

            Anthomedusae . Many of the Anthomedusae are extremely abundant in spring

    and early summer. Sarsia tubulosa (a species recently revised and rationalized

    by Kramp (25) is circumpolar boreal and arctic in distribution; the larger

    Sarsia princeps is an arctic water species. Hybocodon prolifer is an Atlantic

    species which was found in West Greenland waters by Dr. Paul Hansen in the

    1930’s (24). It seems likely that it is a recent immigrant into that area,

    following the warming of the West Greenland current during the past thirty

    years. The species was also found in large numbers at Lake Harbour, southern

    Baffin Island, during July and August 1939 and 1940 (8), so that the intrusion

    of Atlantic water into Hudson Strait must be supposed to extend at least as

    far as that station. Three North Atlantic species of Euphysa are also

    recorded from West Greenland, and the present records from that region con–

    tain many other Atlantic immigrants. Bougainvillia superciliaris is a common

    arctic and boreal form (both Atlantic and Pacific); B. principis is an

    Atlantic form recently found farther north. Rathkea octopunctata and

    Leukartiara brevicornis are both Atlantic and Pacific species recorded from

    West Greenland and from northern Alaskan waters. Catablema vesicarium ,

    C. multicirrata , Halitholus pauper , and H. cirratus are all arctic-boreal

    forms, and all of them, except the Pacific Catablema multicirrata , are

    circumpolar.

            Leptomedusae . The Leptomedusae are less well represented in the North.

    Ptychogena lactea is an arctic water, circumpolar form. There are several

    015      |      Vol_III-0569                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    recent arrivals in West Greenland, including Halopsis ocellata , also first

    recorded by Kramp (26), and discussed by Jensen (2) in his account of

    [ ?] climatic changes in West Greenland.

            Trachymedusae . Only one of the Trachymedusae can be said to be common,

    namely Aglantha digitale , which is arctic and boreal, found in both the

    Atlantic and the Pacific. Several distinct races and variants of this

    species have been described from various parts of its wide range. There

    are a few boreal Trachymedusae which are occasionally found in arctic water and

    two arctic bathypelagic species, Ptychogastria polaris and Botrynema ellinorae ,

    are also occasionally found in deep Atlantic water.

            Narcomedusae. Aeginopsis laurenti is an arctic species, circumpolar in

    range. Aeginura grimaldii Aeginura grimaldii is a cosmopolitan deepwater form.

            Scyphomedusae . Scyphomedusae are rare in pure arctic water, but in

    subarctic areas they are quite common; all of them are fairly widely distri–

    buted in temperate regions. Species found in subarctic water include Cyanea

    capillata (Atlantic and Pacific), Aurelia limbata (Pacific species),

    Halimocyathus lagena and Lucernaria quadricornis (both boreal Atlantic species),

    and a few cosmopolitan forms such as Periphylla hyacinthina and Atolla wyvillei ,

    both bathypelagic forms (24).

            Siphonophora . There is only one species [ ?] of siphonophoran at all common

    in the North, Diphyes ( Dimophyes ) arctica , an almost cosmopolitan species

    found at considerable depths in temperate and tropical regions, and at all

    depths in the Arctic. In strongly subarctic regions such as West Greenland,

    a variety of boreal species are found as immigrants (27).

            Ctenophore. Mertensia ovum is typical of arctic water, and v a e ry common,

    Beroë cucumis is a bipolar species . , found in the Arctic and the Antractic,

    016      |      Vol_III-0570                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    and in the deep Atlantic water in between. Bolinopsis infundibulum is an

    arctic-boreal species, circumpolar in distribution, but much less abundant

    than the other two species.

           

    Protozoa

            The protozoa of the arctic and subarctic seas are not at all well

    known. For a general review of the planktonic protozoa of the temperate

    North Atlantic, the reader is referred to Volume 7 of the periodical Nordisches

    Plankton , published in Germany between 1901 and 1913, in which a few species

    reported from West Greenland are described. Hardy (17) describes eight

    species of the family Tintinnidae (Ciliata) taken by the Nautilus expedition

    in 1931, and speaks of them as “a prominent feature of the collection.” They

    included five species of Cytharocyclis , Ptychocyclis drygalski (the most

    abundant form), Amphorella norvegica , and Tintinnus accuminatum .

            No attempt has been made here to supply complete lists of the known

    arctic and subarctic planktonic species. Such a list would be long and tedious,

    and would serve no useful purpose. Emphasis has been laid on the dominant forms.

           

    Distribution

            The plankton can be divided into ( 1 ) true arctic species, and ( 2 ) boreal

    or cosmopolitan species whose distribution extends into arctic or subarctic

    waters. In the second group, the commoner species are found in both Atlantic

    and Pacific; thus the great majority of the species mentioned above are

    circumpolar in distribution, and any apparent patchiness in the distribution

    of a species is likely to be due to lack of field work. The littoral waters,

    over the continental shelf and in fjord regions, are always richer in plankton

    than the oceanic regions, due to the greater availability of nutrient materials

    017      |      Vol_III-0571                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    brought to the surface by vertical interchange of water during the winter.

            The fact that certain common planktonic species are normally confined

    to arctic water has been used to develop a “plankton indicator” technique

    for northern regions similar to that developed in other regions. Thus

    Frost (15) has shown that six species of the dinoflagellate genus Ceratium

    can be used to indicate the presence, in the Newfoundland area, of water of

    various types from arctic to Gulf Stream. C. arcticum and C. longipes are

    the two cold-water indicators. Similarly Russell (33) gives Diphyes arctica ,

    Sagitta maxima , Eukrohnia hamata , Calanus hyperboreus , Metridia longa , and

    Limacina helicina as indicators of cold water (mainly but not entirely arctic)

    entering the North Sea from the north through the Fair Isle Channel. Themisto

    libellula , Pseudalibrotus nanseni , and P. glacialis are useful as arctic water

    indicators in most parts of the North.

            Distribution is a dynamic, not a static, phenomenon. Nowhere is this

    more clearly shown than in the marine plankton, whose distribution is dependent

    upon the major water movements and which, therefore, respond immediately to

    any changes in the hydrography of a given area. This is particularly well

    demonstrated in the waters west of Greenland, where the recent warming of the

    water has greatly altered the planktonic fauna; attention is drawn especially

    to this fact in the consideration of the West Greenland coelenterates, above.

    It is to be regretted that there is no information on the marine plankton of

    the Canadian Eastern Arctic before 1939. It is apparent from the plankton

    found in Hudson Strait and also in Ungava Bay (unpublished data) that there

    is a considerable invasion of Atlantic species in those parts, but it is not

    possible, due to the lack of past information, to gauge any changes which

    may have [ ?] taken place.



    018      |      Vol_III-0572                                                                                                                  
    EA-Zoo. Dunbar; Plankton

            The plankton of the polar sea itself has been studied very little.

    Nansen’s expedition of 1893-96 made plankton hauls which yielded a rather

    poor plankton, although containing many of the typical species. This was

    in the region north [ ?] of the Siberian coast and westward to the meridian of

    Spitsbergen. Wilkins’ Nautilus submarine expedition in 1931 made plankton

    hauls in the upper 100 meters with a No. 25 net (and one haul up from 250 meters

    with a No. 10 net) at five stations north of Spitsbergen, along the edge of

    the ice between latitude 81° and 82° N. (17). Here again a typical arctic

    plankton was found. Russian zoologists have more recently made a study of the

    marine plankton north of Siberia, over the shelf, and, in 1937, the Papanin

    expedition obtained plankton almost at the North Pole itself, hauling the nets

    through the ice (36).

            Nansen came to the conclusion that the polar sea was an arctic desert,

    containing little or no life (31). This was not confirmed by the Russian

    expedition. Hauling their plankton nets from depths as great as 3,000 meters,

    they obtained during July and August a considerable variety of plankton,

    though not in any remarkable bulk compared to arctic water outside the ice

    cover, or to subarctic water. All the commoner copepods were obtained, and

    the layer of Atlantic water, underlying the polar water from 250 to 750 meters

    in depth, contained typical Atlantic species such as Calanus finmarchicus ,

    Microcalanus pygmaeus , Pareuchaeta norvegica , and Oithona similis .

            Such a zooplankton must depend on a considerable growth of phytoplankton.

    Here again, the Russians upset Nansen’s conclusion. It had been though that

    the ice cover of the polar sea, which is three meters thick on the average,

    with its light snow layer overlying it, would reduce the light which penetrated

    to the water so much that plant life could not exist there, and that the

    019      |      Vol_III-0573                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    phytoplankton growth in the polar sea must be restricted to the open leads in

    the ice which open and close from time to time. The Papanin expeditions, how–

    ever, found that, although the phytoplankton growth in July was very poor,

    there was a considerable flowering in August, by which time the snow cover

    had melted and pools of meltwater covered the ice-field surface. The euphotic

    zone varied in depth, according to the condition of the ice, from three to

    twenty meters. The presence of considerable quantities of phytoplankton

    beneath the ice in summer is also recorded at Point Barrow by MacGinitie

    ( in litt . ), who writes: “Apparently there is some correlation between the

    abundance of diatoms and the angle with which the rays of the sun strike the

    ice.”

            It is interesting that there appears to be only one phytoplankton peak

    during the season in the polar basin, occurring in August, and not two separate

    peaks in spring and fall, such as are found in temperate waters and also in

    subarctic and arctic waters where the ice cover is not permanent all year round.

    Such a “monocyclic” condition was also found by Bogorov (4) along the northern

    sea route from the Kara Sea to the Chukotsk Sea, accounted for by the very

    short period during which light could penetrate into the water.

            A well-known characteristic of plankton, both marine and freshwater, is

    the diurnal vertical migration performed by the majority of the planktonic

    fauna, approaching the surface at night and sinking to lower layers during

    the day. It has long been known that light intensity is the dominant factor

    in controlling this migration; it was suggested many years ago, first by

    Walther in 1893, that the presence of the sun above the horizon at midnight

    would inhibit this upward migration of the plankton. Being surprised to find

    evidence of diurnal migration in the medusa at Spitsbergen, he attempted to

    020      |      Vol_III-0574                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    to explain it by the hypothesis that they were subarctic forms which had

    been carried to Spitsbergen in the Atlantic drift, and that the migration

    was due to the persistence of such a physiological rhythm that the habit

    of diurnal migration was continued even under conditions of arctic summer

    nights.

            Russell (34) pointed out that this argument was unconvincing, since

    even at that latitude (80° N.) the calculated solar radiation which pene–

    trated the surface of the water at midnight in June was only 0.590 gram calorie

    per square centimeter per minute, compared to 1.223 gram calories per square

    centimeter per minute at noon, which he considered a large enough difference

    to account for normal diurnal vertical migration. Bogorov (5) has since pub–

    lished his findings in the Barents Sea, in which he finds no evidence of

    vertical migra a tion during the height of summer; a little farther south,

    however, in the southern part of the White Sea, the normal vertical movement

    is apparent, and in September and October the vertical migration has returned

    to the plankton in the Barents Sea. Furthermore, he points out that according

    to the work of Zubov (41), tidal phenomena in the open sea cause considerable

    vertical movement of water particles in the upper layers, so that the mainte–

    nance by plankton of a constant level throughout the 24-hour day must entail

    considerable swimming activity up and down. This is clearly a most interesting

    problem in the biology of arctic plankton, and one which is probably still far

    from elucidation.



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    EA-Zoo. Dunbar; Plankton


    BIBLIOGRAPHY

    1. Barnes, T. C. “The physiological effect of trihydrol in water,” Nat.Acad.

    Sci., Wash., Proc . vol.18, pp.136-37, 1932.

    2. ---, and Jahn, T.L. “The effect of ice and steam water on Euglena,

    Ibid . vol.19, pp.638-40, 1933.

    3. ----, and ----. “Properties of water of biological interest,” Quart .

    Rev.Biol . vol.9, no.3, pp.292-341, 1934.

    4. Bogorov, B.G. “Biological seasons of the Arctic Sea,” Akad.Nauk.

    Comptes Rendus (Doklady) vol.19, no.8, pp.641-44, 1928.

    5. ----. “Peculiarities of diurnal vertical migrations of zooplankton in

    polar seas,” J.Mar.Res. vol.6, no.1, pp.25-32, 1946.

    6. Brandt, K. “Ueber den Stoffwechsel im Meere,” Wissenschaftliche Meeres–

    untersuch
    . Abt.Kiel , n.s., vol.6, 1899.

    7. Dunbar, M.J. “The breeding cycle in Sagitta elegans arctica Aurivillius,”

    Canad.J.Res . Ser.D, vol.19, no.9, pp.258-66, 1941.

    8. ----. “Marine macroplankton from the Canadian Eastern Arctic. II.

    Medusae, Siphonophora, Ctenophora, Pteropoda, and

    Chaetognatha,” Canad.J.Res . Ser.D, vol.20, pp.71-77, 1942.

    9. ----. “Marine young fish from the Canadian Eastern Arctic,” Canada.

    Fisheries Res.Brd. Bull . no.73, 1947.

    10. ----. “Note on the delimitation of the arctic and subarctic zones,”

    Canad.Field Nat . vol.61, no.1, pp.12-14, 1947.

    11. ----. “On the food of seals in the Canadian Eastern Arctic,” Canad.J .

    Res . Ser.D. vol.19, pp.150-55, 1941.

    12. ----. “On the size distribution and breeding cycles of four marine

    planktonic animals from the arctic,” J.Animal Ecol . vol.9,

    no.2, pp.215-26, 1940.

    13. ----. “On Themisto libellula in Baffin Island coastal waters,” Canada.

    Fisheries Res.Brd. J . vol.6, no.6, pp.419-34, 1946.

    14. Ehrenbaum, E. “Eier und Larven von Fischen,” Nordisches Plankt . Vol.1,

    1905, 1909.

    15. Frost, N. “The genus Ceratium and its use as an indicator of hydrographic

    conditions in Newfoundland waters,” Newfoundland. Nat.Res.

    Dept. Res. Bull . no.5, 1938.



    022      |      Vol_III-0576                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    Bibliography

    16. ----, Lindsay, S.T., and Thomposon, H. “Plankton section,” Newfoundland.

    Nat.Res.Dept., Fish.Res.Div. Ann.Rep . vol.2, no.1, pp.58-67,

    1933.

    17. Hardy, A.C. “The arctic plankton collected by the Nautilus expedition,

    1931. Part I - General account,” Linnean Soc. J . ( Bot .)

    vol.39, pp.391-403, 1936.

    18. Harvey, H.W. “On the rate of diatom growth,” Marine Biol.Ass.U.K. J .

    vol.19, pp.253-75, 1933.

    19. ----. Recent Advances in the Chemistry and Biology of Sea Water.

    Cambridge, Engl., Cambridge University Press, 1945.

    20. Hesse, R., Allee, W.C., and Schmidt, K.P. Ecological Animal Geography .

    N.Y., Wiley, 1937.

    21. Jensen, A.S. “Concerning a change of climate during recent decades in the

    arctic and subarctic regions,” Danske Vidensk.Selsk.

    Biologiske Medd. Vol.14, no.8, pp.1-75, 1939.

    22. Jespersen, P. “Godthaab expedition. Copepods,” Medd.Gronland vol.79,

    no.10, 1934.

    23. ----. “Investigations on the Copepod fauna in east Greenland waters,”

    Ibid . vol.119, no.9, 1939.

    23a. ----. “On the size of Calanus hyperboreus Krøyer in west Greenland

    waters.” Internationale Rev. der Gesamt. Hydrobiol .

    u. Hydrogr. vol.34, pp.102-07, 1937.

    24. Kramp, P.L. “Medusae, Godthaab Expedition,” Ibid . vol.81, no.1, 1942.

    25. ----. “Medusae. Part 2. Anthomedusae,” Danish Ingolf Exped. vol.5,

    no.10, 1926.

    26. ----. “A revision of the medusae belonging to the family Mitrocomidae,”

    Dansk Naturhist.Foren. Copenhagen, Vidensk.Medd . vol.92,

    pp.305-84, 1932.

    27. ----. “Siphonophora, Godthaab, Expedition, “ Medd.Grønland vol.80, no.8,

    1942.

    28. Kreps, E., and Verzhbinskaia, N. “Seasonal changes in the phosphate and

    nitrate content and in hydrogen ion concentration in the

    Barents Sea,” Conseil Perm.Internat.Explor.Mer, J . vol.5,

    pp.326-46, 1930.

    29. Madsen, H. “Investigations on the shore fauna of east Greenland with a

    survey of the shores of other arctic regions,” Medd.Grønland

    vol.100, no.8, 1936.



    023      |      Vol_III-0577                                                                                                                  
    EA-Zoo. Dunbar; Plankton

    Bibliography

    30. ----. “A study of the littoral fauna of northwest Greenland,” Ibid .

    [ ?] vol.124, no.3, 1940.

    31. Nansen, Fridtjof. The Oceanography of the North Polar Basin . London,

    Longmans, 1902. Norwegian North Polar Expedition 1893-96.

    Sci.Res . vol.3, no.9.

    32. Riley, G.A. “Plankton studies. IIII. Long Island Sound,” Yale Univ.

    Peabody Mus.Nat.Hist. Bingham Oceanogr.Fndtn. Bull .

    vol.7, no.3, 1941.

    33. Russell, F.S. “Hydrographical and biological conditions in the North

    Sea as indicated by plankton organisms,” Conseil Perm.

    Internat.Explor.Mer, J . vol.14, pp.171-92, 1939.

    34. ----. “The vertical distribution of plankton in the sea,” Biol.Rev .

    vol.2, pp.213-62, 1927.

    35. Ruud J.T. “On the biology of the southern Euphausiidae,” Hvalrådets Skr .

    no.2, 1932.

    36. Shirshov, P.P. “Oceanological observations,” Akad.Nauk. Comptes Rendus

    ( Doklady ) vol.19, no.8, pp.569-80, 1938.

    37. Sømme, J.D. “Lengievariationer hos Calanus hyperboreus ,” 18de

    Skand.Naturforskermøde , Copenhagen, pp.527-28, 1929.

    38. Stephensen, K. “Crustacea Malacostraca, 5. Amphipoda (1),” Danish

    Ingolf Expedition vol.3, no.8, 1923.

    39. Willey, A. “Biological and oceanographic conditions in Hudson Bay.

    4. Hudson Bay copepod plankton,” Contr.Canad.Biol. & Fisb .

    n.s., vol.6, no.25, pp.483-92, 1931.

    40. Wilson, C.B. “The copepods of the plankton gathered during the last cruise

    of the ‘Carnegie’,” [ ?] Carnegie Inst.Wash. Publ . no.536,

    1942.

    41. Zubov, N.N. “Gidrologicheskie raboty Morskogo Nauchnogo Instituta v

    Iugo-Zapadnoi chasti Barentsova Moria letom 1928 g. na

    E/S ‘Persei,’” (Hydrological investigations in the south–

    western part of the Barents Sea during the summer 1928.),

    Gosudarstvennyi Okeanogr.Inst. Trudy vol.2, no.4, 1932.

           

    Max M . J. Dunbar

    Arctic and Subarctic Inverterbrates of Economic Importance


    001      |      Vol_III-0578                                                                                                                  
    EA-Zoology

    (M. J. Dunbar)


    ARCTIC AND SUBARCTIC INVERTERBRATES OF ECONOMIC IMPORTANCE

           

    Introduction

            Ultimately, all animals in the North may be considered to be of

    economic importance, however distantly, since each species plays its part

    in the total ecology, of which animals of immediate economic importance

    to man form only a comparatively small fraction. But that is not the

    significance intended in the title of this article. It is the intention

    here to discuss briefly invertebrates in the Arctic and Subarctic which are

    either of direct economic value to man, or which play a dominant role in the

    biology of animals which are of direct value to man, whether these latter

    animals are invertebrate or vertebrate.

            In the former group are included certain invertebrates which, although

    not at present used economically by Eskimos or others, offer possibilities

    of such use in the light of recent knowledge In the latter group, those

    of indirect importance to man’s economy in the North, only those of clearly

    dominant position are included. Parasites, although obviously important as

    disease-producers, are not included; nor are biting flies, although they have

    a damaging effect upon human activities in the northern summer, as the recent

    Canadian work on their control testifies.



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    EA-Zoo. Dunbar; Invertebrates of [ ?] Economic [ ?] Importance

           

    Invertebrates of Direct Economic Value

            The deepwater prawn, Pandalus borealis , is by far the most important

    animal in this category. Commercial fishing for Pandalus began in Norway,

    in 1898, following the exploratory work of Johann Hjort and C. G. J.

    Petersen. The fishery continued at a low level until 1920, when it began

    to grow rapidly up to over 3,000 tons taken in 1935 (7). On a smaller scale,

    prawn fishing was started also in Sweden in 1902, and by Denmark in 1930.

    The total weight of prawns landed by all three countries in 1935 was a little

    under 5,000 tons. Most of the prawning grounds in Scandinavian waters are

    at depths between 60 and 250 meters, but the prawns are found down to much

    greater depths.

            Experimental fishing for Pandalus borealis in Greenland began in 1934,

    in fjords of the Holsteinsborg district on the west coast, and in 1935 a

    small cannery was established and was already producing canned prawns.

    The production increased to about 70 metric tons by 1939, but was brought

    to a temporary stop by wartime conditions. The cannery opened up again after

    the war, and exploratory trawling brought to light new trawling grounds in

    the Godthaab District, the Julianehaab District, and in Disko Bay. The

    latter grounds are perhaps the largest of any known prawn beds. New

    canneries have been built at Narssak, in the Julianehaab District, and at

    Egedesminde, at the mouth of Disko Bay (4; 5; 6).

            The Greenland prawn grounds lie deeper than in Norway, for the most

    pa d r t. Most trawling is done at about 400 meters, the deepest trawling bottom

    so far found being apparently south of Ata Sound, in Disko Bay, at a depth of

    445 metres. As a Norway, the prawns congregate on bottoms of a particular

    kind, a firm mud with plenty of detritus; and for good trawling con x d itions the

    bottom must of course be free of rocks. The best type of trawling bottom

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    will produce a characteristic track on the echo-sounder paper (7), a multiple

    tra d c e c d ue to echoes from different layers of mud or sandy mud.

            The life history of Pandalus borealis is of special interest. Like

    several decap e o d crustaceans, it is a protandric hermaphrodite; each individual,

    after a planktonic larval life, goes through a stage of a functional male,

    followed by metamorphosis into a functional female stage, in which stage it

    remains for the rest of its life. The following account of the Greenland

    deepwater prawn is taken (in translation) from Hansen (5):

            “…..It is evident that the Greenland prawn, in its life history,

    agrees with the deep-water prawn that is found at Spitsbergen, and upon

    which the Norwegians have undertaken research work. The eggs which the

    female prawn carries on her swimmerets are laid in July and hatch in the summer,

    and the young larvae are found in the upper layers of the water. It takes

    two years for the larvae to become mature males. They remain as males for

    two years, after which time they change sex and become females; they stay

    females for the rest of their lifetime. The females are thus older and there–

    fore larger than the males. We do not yet know exactly how long they remain as

    females, but it is at least two years, so that the prawns live at least six

    years altogether. Trawling in Disko Bay has shown that the females lie

    farther out from the coast than the males. Trawling near the coast produces

    predominantly males and immature young, while trawling some sea-miles from the

    land yields femal e s in much larger numbers.”

            Pandalus borealis has recently been discovered in large numbers in the

    waters of Newfoundland, the Gulf of St. Lawrence, and the Labrador, in depths

    over 100 fathoms, the limits of the explored range being Anticosti Island,

    southwest Newfoundland, along the northern edge of the Grand Banks, and extending

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    (possibly not continuously) up to Nachvak in northern Labrador. It is

    possible that they go still farther north on this coast, perhaps into

    Ungava Bay; but exploration in the Ungava Bay region has so far not reached

    the depths at which Pandalus borealis may be expected, and moreover the

    bottom has been found to be very unsuitable for trawling, at least in depths

    [ ?] down to a hundred fathoms. Furthermore, the temperatures at

    these depths in Ungava Bay are below zero Centigrade, probably during the

    whole of the summer season, which is somewhat lower than the temperature

    range at which Pandalus has been found on the Labrador coast, or in Greenland

    waters.

            The general known distribution of Pandalus borealis , at present, is as

    follows: Pacific and Atlantic oceans; in the Atlantic, from the waters of

    Denmark and the Dogger Bank northward to Spitsbergen, where it is found as

    far north as Hinlopen Strait and the north of Northeast Land; eastward to

    the Barents Sea and in the Kara Sea to 78° 30' E.; Iceland, southeast Greenland,

    and up the west Greenland coast to 75° 30' N; from Cape Cod to Nachvak,

    Labrador. In the Pacific, it is known from the waters off Japan, in the Sea

    of Okhotsk, and from the waters round the Aleutian Islands, along the south

    coast of Alaska southward to the mouth of the Columbia River, latitude 46° N.

    (7). It has been recorded from Bering Strait, but it is not common in the northern part of the Bering sea, and the known in purely

    Bering Strait record (Maud expedition) seems to work the extreme limit of range in arctic water. It is thus a subarctic-boreal form.

    that region. It is not known in purely arctic water. It is thus a subarctic-boreal form.

            Prawns of other species than Pandalus borealis have been found in

    promising numbers in the northern part of the Bering Sea, by a trawling

    survey in 1949, sent out by the U.S. Fish and Wildlife Service. The survey

    was partly in response to numerous reports from local residents that there

    existed in the northern Bering Sea species of animals, from cod to shrimps

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    EA-Zoo. Dunbar; Invertebrates of Economic Importance

    which might have a commercial value. Five species of shrimps or prawns

    (the vernacular terms are interchangeable) were caught “mainly in the

    waters around St. Lawrence Island and the approaches to Norton Sound.

    Considering the large mesh of the trawl used (3″mesh in the bag, 6″ in the wings

    and square), the numbers of gray shrimp ( Argis lar ) taken may be considered

    sufficient to justify further investigation with g r ear more suitable for

    shrimp fishing.” ( 3). The shrimps were caught in depths down to 40 fathoms,

    mainly in water of temperatures between 0° and 4°C. Besides Argis lar , the

    following four species were taken: Pandalus gonirus , P. hypsinotus , Spiron–

    tocaris
    groenlandica , and Sclerocrangon boreas .

            The same Bering Sea survey in 1949 [ ?] studied the occurrence of king

    crabs ( Paralithodes — not to be confused with the totally different Atlantic

    “king crab,” Limulus, which is an arachnid, not a crustacean). King crabs

    are at present fished commercially in the southern part of the Bering Sea.

    In the northern part, “King crabs were widely scattered and of a much

    smaller size than those found to the south. Both the Alaskan and purple

    species were taken, and although no great quantities were found, it is

    possible that a more thorough survey might reveal areas of concentration.

    The shoal conditions in the northern area make it difficult to predict crab

    movements there on the basis of knowledge gained in the southern regions of

    deeper waters.” (3). The two species found were Paralithodes camtschatica

    and P. platypus . They were taken in shallow water only, in depths down to

    30 fathoms, and most of them were found at temperatures between 0° and 4° C.

    Only 100 specimens were taken in the 51 drags made.

            The deepwater prawn is the only invertebrate at present exploited

    commercially in northern waters, and it is not itself a truly arctic form.

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    The prawns and king crabs taken in the northern Bering Sea may offer

    possibilities of future use; they too are not arctic water forms, and

    are not found in water of negative temperature. Arctic water itself,

    then, by which is meant water originating in the Polar Sea and not mixed

    with temperate waters, has so far not produced any commercial fishing for

    invertebrates. Nor in fact does it offer many fishes in sufficient numbers

    for such exploitation. The only invertebrate that is used to any extent

    as food by the Eskimos, namely the blue mussel, Mytilus edulis , is also a

    subarctic-boreal animal, not found in pure polar water.

            Mytilu m s edulis is circumpolar in distribution, from the northern limits

    of the marine Subarctic southward in the Atlantic and Pacific to San Fran–

    cisco on the American Pacific coast, North Carolina on the Atlantic side,

    and the coast of Portugal in western Europe. In the north, it is one of the “indicator” littoral species by which a good estimate of

    the limits of influence of nonarctic water can be made (2; 8; 9; see also

    “Littoral Fauna” in this Encyclopedia). It shows a gradient of abundance,

    decreasing northward. It is known as far north as Thule in West Greenland,

    and it is found along the Labrador coast and in Ungava Bay. It is not common

    in Ungava Bay, except at Port Burwell, where there is a bed exposed at spring

    tides which is made use of by the native population. Wherever it occurs it

    occurs in any numbers, it is eaten by the Eskimos as a pleasant change

    in diet, and a very healt h y one. Sometimes whole meals of blue mussels are

    eaten, especially in areas of abundance in West Greenland.

            Other invertebrates are of much less importance to the Eskimos. Shrimps,

    whelks ( Littorina — also a subarctic and boreal form) and the ovaries of

    the sea urchin ( Strongylocentrotus ) are occasionally eaten when casually

    picked up, or when starvation threatens, but they are of very minor signify–

    cance. In subarctic areas, similar to those in which Mytilus is found in

    007      |      Vol_III-0584                                                                                                                  
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    the North, Littorina is very abundant in summer, and although small in size

    could be eaten in greater quantities than is the fact at present.

            In periods of great threat of starvation, when in fact di s aster threatens,

    invertebrates have figure s d in the diet of several expeditions. The best

    example of this was the Greely expedition to Ellesmere Island, one of the

    first International Polar Year parties, in 1882-83. During the last stages

    of exhaustion, when the relief ship had failed to appear, Greely’s diary

    records that “shrimp” were caught in a net, at the surface of the water,

    and carefully rationed among the survivors. The cook was caught stealing

    these “shrimps,” and on repeating the offence after due warning, was shot;

    a good instance of the vital importance, on one occasion, of invertebrates

    in the Arctic. These animals were taken in pure arctic water, close to the

    surface, and it is probable that they were in fact Themisto libellula , an

    amphipod crustacean of great abundance in arctic water, and one of the very

    few forms found at the surface in large numbers. It is also possible that

    the animals concerned were Gammarus locusta .

           

    Invertebrates of Dominant but Indirect Economic Importance.

            This section will be covered only very briefly. In arctic and subarctic

    environments, particularly marine environments, there are invertebrate forms

    so dominant in the animal populations that they form almost exclusive diets

    for larger animals, at least during certain seasons. The following list

    includes only those animals that fall into this category, very often forming

    monospecific populations locally, sometimes over wide areas, and thus figuring

    as the direct support of animals of economic value to man: The amphipod

    crustacean Themisto libellula , Anonyx nugax , Pseudalibrotus littoralis ,

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    Gammarus locusta , and (in fresh water) Pontoporeia affinis ; the euphausiids

    Thysanoessa raschii and T. inermis , and Meganyctiphanes norvegica ; the mysids

    Mysis oculata and (in fresh water) Mysis relicta ; several copepods, more

    especially Calanus hyperboreus , C. finmarchicus and Metridia longa ; and the

    mollusk Limacina helicina .

            All these are “key industry” or dominant species in their respective

    ecological territories. Themisto libellula is an upper - water form, deeply

    pigmented and apparently able to tolerate the direct rays of the sun at the

    surface. It is the most important of all food organisms of the ringed seal,

    Phoca hispida (1). Seal stomachs are often found to be entirely filled with

    nothing else but Themisto . It has also been found frequently in the stomachs

    of the harp seal, Phoca groenlandica , and of the arctic char, Salvelinus

    alpinus , and it is important in the food of sea birds in the Arctic. As a

    link between the smaller planktonic crustaceans and the larger predators it

    is perhaps the most important animal in the North, in any environment. Like

    all the other animals in the present list, it is circumpolar in distribution.

            Anonyx nugax , another abundant form in both the plankton and the

    littoral fauna, is found in deeper water than Themisto , except in the littoral

    zone, where Themisto does not occur. It is eaten in large numbers by inshore

    fishes and also plays an important part in the marine diet of the arctic char.

            Even more numerous than Anonyx is Pseudalibrotus littoralis , which is

    present in enormous numbers in shallow water all over the northern seas.

    Skulls and other skeletal specimens which the present writer has lowered to

    the bottom for cleaning purposes in Ungava Bay, have been hauled back on board

    ship completely filled with this amphipod. It has been found to be by far the

    common food of the arctic char in Frobisher Bay (Grainger, unpublished

    data: see “Arctic C h ar”).



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            Gammarus locusta , the ubiquitous littoral amphipod, is abundant on

    arctic and subarctic shores, and figures in the normal diet of all inshore

    fishes. It is eaten in great numbers by the Atlantic cod ( Gadus callarias )

    in West Greenland and in Ungava Bay (Port Burwell), and is also eaten by

    the arctic char.

            Pontoporeia affinis is perhaps the most common amphipod in freshwater

    environments in the northern regions, and as such is of great importance as

    the main food of ma h n y freshwater fishes of considerable economic importance,

    such as the whitefishes and lake herrings.

            The three euphausiids, Meganyctiphanes and two species of Thysanoessa ,

    collectively known by the vernacular Norwegian name of krill , are pelagic

    forms found in large numbers over a wide depth range. They are not usually

    found very close to the surface, and thus do not complete with Themisto for

    dominance. They have been found in the stomachs of sea birds (eider duck,

    old squaw, kittiwake, murre, etc.), and form one of the chief foods of the

    capelin ( Mallotus villosus ), and of the harp seal in certain parts of the

    North. They are perhaps best known of all as the food of the blue whale

    ( Balaenoptera musculus ), and to a lesser extent of the other rorquals

    (finback, Balaenoptera physalus ; sei whale, B. borealis , etc.).

            Mysis oculata is frequently met with in large schools or swarms in

    shallow water, often where fresh water flows into the sea. It keeps as

    a rule fairly close to the bottom. It is locally important in the food of

    the Atlantic cod, the capelin, and the ringed, harp. And harbor seals.

    The freshwater relict form of Mysis oculata is M. relicta , very common

    in many lakes.

            The copepod plankton form the chief link between the phytoplankton and

    the larger zooplankton, and also form the food of larger animals of great

    010      |      Vol_III-0587                                                                                                                  
    EA-Zoo. Dunbar; Invertebrates of Economic Importance

    economic worth, such as the right whales ( Balaena spp.) and the herring

    ( Clupea harengus ). The dominant forms in the North are Calanus finmarchicus

    and C. hyperboreus , together with a few other genera such as Metridia ,

    Oithona , and others. (See “Marine Plankton”)

            The little “sea butterly,” Limacina helicina , appears in vast numbers

    in the surface waters of the Arctic in August and September. In northern

    Labrador and at Port Burwell, Ungava Bay, it figures prominently in the

    food of the Atlantic cod. On the Labrador, in fact, the fishermen speak of

    “capelin cod” in the southern half of the coast, where capelin form the

    bulk of the cod diet, and “blackberry cod” in the northern part of the coast,

    “blackberry” being another vernacular name for Limacina. Limacina has also

    been taken in numbers from the stomachs of ringed seal at Clyde River, Baffin

    Island, in September, at a time of year when there is very little else in the

    plankton for the seal to feed upon, at least in the surface layers of the

    [ ?] fjord waters (1). At one time it was thought that

    the occasional bad taste of seal meat, and the poisonous qualities of polar

    bear liver, were referable to the habit of the seal in eating Limacina ; but

    the dangers of eating polar bear liver are now known to be due to factors for

    which it seems quite unreasonable to blame this apparently harmless little

    mollusk. The codfish in Labrador and Ungava Bay waters, which eat Limacina ,

    are perfectly wholesome food.



    011      |      Vol_III-0588                                                                                                                  
    EA-Zoo. Dunbar; Invertebrates of Economic Importance


    BIBLIOGRAPHY

    1. Dunbar, M.J. “On the food of seals in the Canadian eastern arctic.”

    Can.J.Research , D, vol.19, pp.150-55, 1941.

    2. ----. “Note on the delimitation of the arctic and subarctic zones.”

    Can.Field-Nat ., vol.61 (1), pp.12-14, 1947.

    3. Ellison, J.G., Powell, D. E. and Hildebrand, H. H. “Exploratory

    fishing expedition to the northern Bering Sea in Juna and

    July, 1949.” U.S.Dept. Interior; Fish & Wildlife Service,

    Fishery Leaflet No. 369; 56 pp., mimeographed, 1950.

    4. Greenland Administration. “Sammendrag af Statistiske Oplysninger

    om Grønland, IV, 20 Afsnit: Henkogningsstationen ved

    Holsteinsborg.” Beretn.vedr.Gronl.Styrelse , no.1, pp.709-16,

    1945.

    5. Hansen, P. M. “Fiskeriundersøgelserne ved Grønland.” Grønlandposten ,

    vol.8, (8), pp.98-102, 1949.

    6. ----. “Dybhavsrejen ved Grønland.” Grønlandposten, vol.8 (3), pp.26-30,

    1949.

    7. Hjort, J., and Rund, J. T. “Deep-sea prawn fisheries and their problems.”

    Hvalradets Skrifter , no.17, pp.1-144, 1938.

    8. Madsen, H. “Investigations on the shore fauna of east Greenland with

    a survey of the shores of other arctic regions.” Medd.Grøn .

    vol.100 (8), pp.1-79, 1936.

    9. ----. “A study of the littoral fauna of northwest Greenland.”

    Medd.Grøn . vol.124 (3), pp.1-24, 1940.

    10. Rasmussen, B. “Om Dypvannsreken ved Spitsbergen.” Rep. Norwegian

    Fish. & Mar. Investigations , vol.7 (4),

           

    M. J. Dunbar

    Marine Fishes of the North American Arctic


    Unpaginated      |      Vol_III-0589                                                                                                                  
    EA-Zoology (Henry Hildebrand)

    MARINE FISHES OF THE NORTH AMERICAN ARCTIC

           

    CONTENTS

    Page
    Hydrographic Conditions 2
    Ichthyofauna 4
    Summary 16
    Bibliography 17



    001      |      Vol_III-0590                                                                                                                  
    EA-Zoology

    (Henry Hildebrand)


           

    MARINE FISHES OF THE NORTH AMERICAN ARCTIC

            Our knowledge of the fish fauna of the American Arctic is very limited,

    and there is need for much additional work before a clear picture of the

    fauna can be drawn. Even today there are no commercial fisheries in the area

    except in West Greenland. Early explorers were primarily interested in find–

    ing a short route to the riches of Cathay, searching for precious minerals,

    or attempting to reach the North Pole; any zoological exploration was merely

    incidental and was not prosecuted vigorously.

            An immense area is covered by this article — all of the Arctic Sea

    between the longitudes of Cape Farewell, Greenland, and Bering Strait, and

    all the marine waters north of the coast line of continental North America

    including James Bay, which reaches south to approximately 51° N. latitude.

            Demark has consistently held the lead in arctic scientific exploration.

    In fisheries, the brig Tjalfe was outfitted by the Danish Government for in–

    vestigations in Greenland during the years 1908-09; Adolph S. Jensen was the

    leader of this expedition. Among other important fisheries investigations

    in Greenlandic waters was that of the Dana in 1925. Canada has long been aware

    of the vast Hudson Bay, which extend s so deeply southward into her territory.

    Several expeditions have been sent here, the latest and best equipped being

    the Loubyrne fisheries expedition in 1930.



    002      |      Vol_III-0591                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            A new interest has been manifested in this region in recent years, in

    part due to changing hydrographic conditions which have revitalized the

    fishing industry of Greenland, in part to unsettled world conditions. A

    decline in land and sea mammals coupled with increasing native populations

    have incited a greater interest in the ichthyofauna of the seas as a means

    of bettering living conditions. The Canadian Government has had an expedi–

    tion in Ungava Bay for the past four summers (1947-50) for this purpose.

    Several new ships have been built for arctic marine research: the Adolph S .

    Jensen by the Danes, the Calanus by the Canadians; and the Ernest Holt by the

    British.

            The literature concerning arctic fishes is not great and is widely

    diffused in numerous small articles and in narratives of travel and explora–

    tion. A list of impotant references is given at the end of this article.

    The writer wishes to acknowledge his indebtedness to the curators of the

    following fish collections: National Museum of Canada, Royal Ontario Museum

    of Zoology, Chicago Museum of Natural History, United States National Museum,

    and the McGill University collections, for permission to examine specimens

    from the Arctic.

           

    Hydrographic Conditions

            A brief r e é sum e é of hydrographic conditions will help to explain the

    distribution of fishes. However, it must be admitted that much hydrographic

    investigation remains to be done, whole areas being relatively unexplored.

            Pacific Influence . The status is not clearly defined, but the term refers

    003      |      Vol_III-0592                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

    to the warming effect of Pacific water entering through Bering Strait and

    progressing eastward at least to the Mackenzie.

            Mackenzie District . This term is used to define the area where large

    rivers flow into the Arctic Sea; it extends eastward to Back River.

            Arctic Archipelago ( Including Boothia Peninsula ). This area is char–

    acterized for the most part by poor circulation, heavy and continued icing

    for most of the year, and a very limited fauna.

            Hudson Bay and Strait . This region is characterized by low temperature

    and salinity, and well-stratified water layers with little vertical movement.

            Baffin Bay and the East Coast of Baffin Island . This area is charac–

    terized by the cold Arctic Current from Lancaster Sound.

            West Greenland . This is the area south of the submarine ridge across

    the narrowest part of Davis Strait between Greenland and Baffin Island, which

    is warmed by the West Greenland Current and has a bottom temperature of at

    least 3°C.

            Transition Areas . There is some mixture of Atlantic water north of the

    submarine ridge, which permits some forms to migrate farther north, especially

    during the summer months. There is a modified influence of Atlantic water

    around Port Burwell in Ungava Bay, with a change of fauna. Extreme south–

    western Greenland is cooled by the East Greenland Current and is relatively

    arctic in affinities.

            It must be remembered that distribution of organisms is not a static

    but a dynamic phenomenon. Jensen, in 1939, showed how a slight warming of

    the West Greenland Current had so changed the fish fauna in Davis Strait as

    to alter the economy of the Greenlanders during the two preceding decades.



    004      |      Vol_III-0593                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

           

    Ichthyofauna

            A brief review of the ichthyofauna of the American Arctic will be given,

    including each individual species known to occur in the region. However, it

    must be stated that many arctic forms are in a state of chaos taxonomically,

    because of lack of specimens and the marked inadequacy of original descript–

    tions. Classification as used herein was taken from Jordan, Evermann, and

    Clark, Checklist of the Fishes and Fishlike Vertebrates of North and Middle

    America (1930), except where recent publications indicate a change. The

    writer has also referred to a number of monographs on individual groups by

    Ad. S. Jensen for names of forms occurring in Greenland.

            Myxine glutinosa (hagfish): not uncommon in the deep water of Davis

    Strait warmed by the West Greenland Current.

            Petromyzon marinus (sea lamprey): rare, specimens known from South

    Greenland.

            Squalus acanthias (common dogfish, spiny dogfish): formerly rare and

    irregular in occurrence; Jensen states that this species has become more

    common along the west coast of Greenland due to a recent amelioration of

    climate.

            Centroscyllium fabricii (black dogfish): a deep-water form occurring

    in the “warm” water south of the submarine ridge in Davis Strait.

            Somniosus microcephalus (Greenland shark): common along the west coast

    of Greenland from Cape Farewell to Wolstenholme Sound. Other definite locali–

    ties are Port Burwell and the Koksoak River estuary in Ungava Bay. Sight

    records are known from Wakeham Bay, Hudson Strait, Southampton Island, and

    several localities along the east coast of Hudson Bay, south to Great Whale

    River.



    005      |      Vol_III-0594                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            This ground shark is a great carrion eater and will probably eventually

    be found to parallel the distribution of the larger sea mammals in the Arctic.

    It is an important economic fish to the Greenlanders; oil was first extracted

    from the livers in 1805, and during the twentieth century the skins have

    been added as an article of commerce. Nearly 35,000 sharks are taken yearly

    by the Greenlanders, who regularly fish for this large, sluggish animal from

    kayaks and also on fast ice. It offers little resistance when hooked.

            Although numerous specimens of this shark have been taken, its mode of

    reproduction is unknown. The consensus is that it bears its young a b live,

    but this has yet to be proved.

            The meat of the shark when dried is used as dog food, and if necessity

    decress, human food. Fresh shark meat makes dogs violently ill, producing

    what is known as “shark intoxication.” Death may ensue from eating the

    fresh meat.

            Raja radiata : not uncommon along the west coast of Greenland north to

    approximately 69° N. latitude. One specimen from Richmond Gulf, Hudson Bay,

    is known.

            Raja fyllae : not uncommon in deep water south of the submarine ridge in

    Davis Strait.

            Raja hyperborea : inhabits the deep cold water north of the submarine

    ridge and has also been reported from extreme southwestern Greenland.

            Raja lintea : common in the deep “warm” water of Davis Strait.

            Raja spinicauda : distribution same as preceding species, but not as common.

            Acipenser fulvescens (sturgeon): primarily fresh water, occurs in the

    brackish river mouths of James Bay.



    006      |      Vol_III-0595                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            Clupea harengus (common herring): formerly not common in West Greenland,

    although fluctuations in numbers undoubtedly occurred. In recent years,

    herring have increased in numbers and have almost become of economic impor–

    tance. In 1934, two large herring were taken at Prőven, Greenland, in lati–

    tude 72°30' N.

            Clupea pallasii (California herring): migrates sporadically into the

    Arctic from the Pacific, reported as far east as Bathurst Inlet. Anderson

    (1913) records a large school which appeared at Cape Bathurst in August 1911.

            Oncorhynchus gorbuscha (humpbacked slamon): straying along the north

    coast of Alaska at least to the Mackenzie River.

            Oncorhynchus kets (dog salmon): straying through Bering Strait at least

    to the Mackenzie. In 1914, a large run of salmon up the Mackenzie River was

    reported.

            Salmo salar (Atlantic salmon): common only in the rivers of southern

    and eastern Ungava Bay; uncommon in Greenland, reported only from Godthaab

    Fjord, Amerdloq Fjord near Holsteinsborg, and Ikerasak, Sukkertoppen District.

            This is the only fish in the Canadian Arctic ever to have supported a

    sustained commercial fishery. It was shipped direct to London markets from

    Ungava Bay for a number of years, starting in 1881 and continuing until the

    failure of the fishery in 1932. The number caught was not large, but varied

    between 150 to 300 tierces a year.

            Salvelinus fontinalis (brook trout): primarily a freshwater form, but

    has been reported from brackish and salt water in southern Ungava Bay, James

    Bay, and Hudson Bay, at least as far north as the limit of trees.

            Salvelinus alpinus (arctic char, arctic salmon, or salmon trout):

    007      |      Vol_III-0596                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

    anadromous and abundant throughout the Arctic; taxonomic status confused,

    but all species described or reported from this region are included under

    alpinus pending clarification of its taxonomic status. The fish is known

    by a number of common names; in fact, it varies so much according to age or

    ecological habitat that many explorers and travelers have though they were

    dealing with separate species.

            This is the ekaluk of the Eskimo and the most important food fish through–

    out much of the Arctic. Nowhere has it been developed commercially except

    in Greenland, where a few hundred barrels a year are exported to Denmark.

            Stenodus leucichthys (inconnu): anadromous and common in the Mackenzie

    River and tributaries; its eastern limit has been cited as Anderson River,

    and to the west it extends along the arctic coast of Alaska.

            Leucichthys autumnalis : primarily a freshwater form, occurs along the

    arctic coast of Alaska to the Mackenzie.

            Leucichthys sardinella : range similar to preceding species.

            Leucichthys artedi (cisco): occurs in brackish water from Ungava Bay to

    the Mackenzie; distribution along the arctic coast of Canada poorly known. In

    Hudson Bay ciscoes are known to migrate to salt water during the summer.

            Coregonus clupeaformis (common whitefish): primarily in fresh water, occurs

    sparingly to commonly in the brackish water of Ungava, James, and Hudson bays

    and probably the estuaries of the larger rivers along the arctic coast to the

    Mackenzie. In Hudson Bay, whitefish are known to migrate to salt water during

    the summer.

            Prosopium cylindraceum (round whitefish): distribution similar to preceding

    species, but makes a very unsatisfactory growth in the northern part of its Hudson

    Bay range.



    008      |      Vol_III-0597                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            Mallotus villosus (capelin): possibly, when specimens are available,

    two species will be found to occur in the Arctic. Capelin are common along

    the west coast of Greenland and reach latitude 76°30' N. in migration.

    Records are known from Ungava Bay, James Bay, Foxe Basin, Bellot Strait,

    Coronation Gulf, Bathurst Inlet, and Point Barrow. Occurrences are often

    sporadic. In parts of Greenland this form is caught and dried and is known

    as the “daily bread” of the Greenlanders.

            Osmerus dentex (smelt): rare at the mouth of the Mackenzie River and

    along the Alaskan coast.

            Nansenia groenlandica : rare in the deep water of Davis Strait.

            Bathylagus benedicti : deep water of Davis Strait south of the submarine

    ridge.

            Stomias boa : deep “warm” water of Davis Strait, straying to Jacobshavn.

            Cyclothone microdon : deep water of Davis Strait, straying into Baffin Bay.

            Argyropelecus olfersi : rare in the deep water of Davis Strait.

            Notacanthus chemnitzi : rare in the deep water of Davis Strait.

            Notacanthus rostratus : rare in the deep water of Davis Strait.

            Anguilla bostoniensis (= A. rostrata ) (American eel): six specimens known

    from southwest Greenland in the neighborhood of Nanortalik.

            Synaphobranchus pinnatus (long-nosed eel): not uncommon in the deep “warm”

    water of Davis Strait.

            Histiobranchus infernalis : deep water of Davis Strait.

            Saccopharynx ampullaceus : very rare, one specimen known from the entrance

    of Davis Strait.

            Paralepis conregonoides borealis : known from the west coast of Greenland

    from Cape Farewell to Umanak Fjord in latitude 72° N. This form does not breed

    009      |      Vol_III-0598                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

    in the area, and is probably carried into the region by the current. It is

    usually taken dead on the surface, or from fish or seal stomachs.

            Paralepis risso kroyeri : range similar to preceding species, but very

    rare; known from Greenland by only five specimens; also recorded from Port

    Burwell, Ungava Bay.

            Lampanyctus crocodilus (lantern fish): bathypelagic, common south of

    the submarine ridge in Davis Strait; also reported from Port Burwell.

            Lampanyctus elongates (lantern fish): rare and of doubtful occurrence;

    reported from Godhavn, Greenland.

            Myctophum arcticum (lantern fish): bathypelagic; known from Davis Strait.

            Myctophum glacialis (lanter n fish): bathypelagic; common south of the

    submarine ridge in Davis Strait. This lanter n fish has also been recorded from

    Baffin Bay and Port Burwell, Ungava Bay.

            Alepisarus ferox (lancet fish): deep water of Davis Strait and also

    reported from Jacobshavn, Greenland.

            Coryphaenoides rupestris (grenadier): common in the deep water of Davis

    Strait and also in the fjords of West Greenland.

            Macrourus aequalis (grenadier): rare in Greenlandic waters.

            Macrourus berglax (rattail grenadier): a very common macrourid in the

    deep water of Davis Strait.

            Macrourus goodei : rare in our region; known from two specimens taken near

    the entrance of Davis Strait.

            Trachyrhynchus murrayi : known from a single specimen from the west coast

    of Greenland.

            Gaidropsa r us ensis : deep water and rare; reported from Umanak, Greenland.



    010      |      Vol_III-0599                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            Gaidropsarus septentrionalis : rare in the deep water of Davis Strait.

            Ciliate argentata : This species has been taken in the deep water on

    both sides of the submarine ridge in Davis Strait.

            Boreogadus saida (arctic Pollack, polar cod): a common fish throughout

    the Arctic. This is a pelagic salt-water form, which is often found among the

    ice floes. When pursued by the white whale, this fish has been known to

    leap upon the ice floes in its endeavor to escape.

            Recent studies indicate that there may be several species occurring

    in the American Arctic. Arctogadus pearyi and B. agilis have been reported

    from Greenlandic waters, but their status is very uncertain due to the lack

    of comparative specimens.

            Pollachius virens (coalfish): formerly rare in West Greenland waters;

    however, with the recent amelioration of climate, large shoals have been

    seen in the south Frederikshaab district.

            Eleginus navaga (tomcod): This form has been reported from the Mackenzie

    Delta, Bering Sea, Point Barrow, Simpson Strait, and Coronation Gulf. In–

    formation on this species is very scanty.

            Cadus callarias (common Atlantic cod): This fish has known periodic

    cycles of abundance in West Greenland, which are apparently associated with

    climatic changes. Jensen (1939) outlines how a recent climatic change has

    so increased the number of cod as to alter the entire economy of the Green–

    landers. Specimens have been taken as far north as Upernivik in Greenland.

    The fish regularly spawns in Greenland waters. Cod occur at Port Burwell,

    Ungava Bay, during the months of August and September.

            Gadus ogac (Greenland cod): This is a northern species of cod; it

    011      |      Vol_III-0600                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

    prefers rocky grounds and coastal salt water. It has been reported from many

    points in West Greenland, also Ungava Bay, Hudson Bay, Adelaide Peninsula,

    Victoria Island, and Kent Peninsula. Apparently it has not been recognized in

    Alaskan waters.

            Melanogrammus aeglefinus (haddock): very rare; apparently recorded for

    the first time in 1929 in West Greenland.

            Molva molva : very rare; reported from the Frederikshaab District of

    Greenland.

            Brosmius brosme (cusk): a rare form in the area warmed by the West Green–

    land Current.

            Trachypterus arcticus (deal fish): straying into the region warmed by

    [ ?] the West Greenland Current.

            Lampris guttatus : a rare fish in Greenlandic waters.

            Reinhardtius hippoglossoides (Greenland halibut, arctic halibut): a common

    and economically important fish along the west coast of Greenland to Umanak in

    the north. This fish does not spawn in the bays and fjords where the adults

    occur, but out in Davis Strait over deep water. Small specimens have been

    taken at Port Burwell.

            Hippoglossus hippoglossus (Atlantic halibut): common along the west coast

    of Greenland; has been fished as far north as Umanak, and a few strays have

    been taken at Upernivik.

            Hippoglossoides platessoides (sand dab): occurs along the west coast of

    Greenland to Umanak in the north.

            Platichthys stellatus (California flounder): This species has been re–

    ported from Langton Bay, Kittigazuit, Coronation Gulf, and Queen Maud Gulf in

    the Northwest Territories.



    012      |      Vol_III-0601                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            Liopsetta glacialis (arctic flounder): This species is reported from

    Bathurst Inlet, Bernard Harbour, and Queen Maud Gulf in the Northwest Ter–

    ritories. The arctic flounder, like the preceding species, has no economic

    importance in the Arctic.

            Glyptocephalus cynoglossus (witch flounder): reported from Davis Strait

    south of the submarine ridge.

            Gasterosteus aculeatus (three-spined stickleback): common in small brackish

    water streams throughout the Arctic, except the extreme north.

            Pungitius pungitius (nine-spined stickleback): common throughout most of

    the Arctic except Greenland. It does not occur in the brackish streams in

    Greenland.

            Sebastes marinus (rose fish): This fish occurs along the coast of Greenland

    from Cape Farewell to 71° N. latitude; a deep-water fish of commercial importance

    in Greenland. Two small specimens have been reported from Port Burwell.

            Artediellus uncinatus (hook-eared sculpin): reported from Davis Strait

    in deep water, also Dolphin and Union Strait in the Northwest Territories.

            Icelus bicornis (two-horned sculpin): This species probably occurs through–

    out the Arctic; however, it has been reported only from West Greenland, southern

    Ellesmere Island, Jones Sound, Hudson Bay, Foxe Basin, and Dolphin and Union

    Strait.

            Triglops pingeli (mailed sculpin): This sculpin has been recorded from

    Dolphin and Union Strait, Hudson Bay, Ungava Bay, and the entire west coast of

    Greenland. This is a deep-water sculpin although occurring in shallow water

    in the northern part of its range.



    013      |      Vol_III-0602                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            Triglops nybelini : a high-arctic sculpin occurring in Greenland to 78° N.

    latitude, and apparently inhabiting deeper water than T. pingeli .

            Myoxocephalus scorpius (common sculpin): This is a common littoral sculpin

    and is rarely taken below 30 meters. It is abundant along the west coast of

    Greenland, north to Thule, where it is replaced by Oncocottus quadricornis .

    In Ungava Bay this is the commonest shore sculpin. While M. scorpius has been

    reported from James Bay, Hudson Bay, Foxe Basin, Dolphin and Union Strait, and

    Devon Island, it is not as common in those regions as O. quadricornis .

            Myoxocephalus scorpiodes : This is a small littoral sculpin closely re–

    sembling M. scorpius , reported as far north as Etah along the west coast of

    Greenland. It is common in James and Hudson bays, living in the littoral zone.

    Although reported from Foxe Basin and Dolphin and Union Strait, this form is

    evidently rare along the coast of arctic Canada, and is apparently unknown

    from Alaskan waters.

            Porocottus polaris : a small cottoid, whose affinities are unknown, reported

    from Melville Island and Boothia Peninsula.

            Oncocottus quadricornis (four-horned sculpin): a high-arctic littoral

    sculpin replacing M. scorpius in Greenland, north of Thule; often used as an

    indicator of high-arctic waters. This sculpin is known from the north coast

    of Ellesmere Island and holds the farthest north record of a marine fish.

    Along the arctic coast of North America, this is much commoner than M. scorpius .

            Gymnocanthus tricuspis (stag-horned sculpin): a common sculpin along the

    coast of Greenland north to Etah; also known from Jones Sound, east Baffin

    Island, Ungava Bay, Hudson Bay, and Foxe Basin. The Pacific form G. galeatus

    was identified from Hudson Bay on the basis of a single specimen.



    014      |      Vol_III-0603                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            Gymnocanthus pistilliger : known from the northern coast of Alaska to

    Dolphin and Union Strait.

            Cottunculus microps : deep water of Davis Strait on both sides of the

    submarine ridge.

            Cottunculus thompsonii : rare in the deep water of Davis Strait.

            Leptagonus decagonus : common in Greenlandic waters north to Smith Sound

    on the west coast; also reported from Exeter Sound and Lake Harbour, Baffin

    Island.

            Aspidophoroides monopterygius (sea poacher): along the coast of Green–

    land from Ivigtut to Jacobshavn, and from Exeter Sound, Baffin Island.

            Aspidophoroides olriki : common along the coast of West Greenland from

    67° to 71° N. latitude; elsewhere reported from Ungava Bay, Hudson Strait, and

    Hudson Bay.

            Cyclopterus lumpus (lumpfish): common in the southern part of its range

    along the coast of Greenland from Cape Farewell to Umanak; also reported

    from James Bay and the Churchill district of Hudson Bay.

            Eumicrotremus spinosus (spiny lumpfish): common along the entire west

    coast of Greenland to Etah; also reported from Ungava Bay, Hudson Strait and

    Hudson Bay, and Foxe Basin.

            Eumicrotremus derjugini : recognized only from Hudson Bay.

            Cyclopteropsis malcalpini : known from type locality, Ulrik Bay, Greenland.

            Lethrotremus armouri : known only from Upernivik, Greenland.

            Liparis spp. (sea snails): Considerable confusion exists concerning the

    systematic position of the liparids in northern waters. L. atlanticus has

    been doubtfully identified from Ungava Bay. L. tunicatus is common along the

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    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

    coasts of Greenland, Ungava Bay, Cumberland Sound, Foxe Basin, and Jones

    Sound. L. major is known from Greenland north to Etah. L. cyclostigma , a

    Bering Sea species, is known only from Hudson Bay in our region.

    L. herschelinus is known from Alaska and Herschel Island, Northwest Ter–

    ritories.

            Careproctus reinhardti : a deep-sea fish which has been reported

    from Umanak and Jacobshavn, Greenland.

            Ammodytes lancea (sand launce): a common fish from Julianehaab dis–

    trict to Umanak, Greenland. This species had also been reported from Ungava

    Bay, Hudson Bay, and Kent Peninsula, Northwest Territories. A number of

    subspecies have been recognized.

            Pholis gunnellus (gunnel): known from the Greenland coast between

    Julianehaab and Ho l steinsborg.

            Pholis fasciatus (rock eel): an inhabitant of the shore salt water

    along the Greenland coast north to 73° N. latitude; also reported from Devon

    Island and Hudson Bay.

            Stichaeus punctatus (spotted snake blenny): common in the shore zone of

    West Greenland to 73° N. latitude; also reported from Hudson Bay.

            Eumesogrammus praecisus : distribution the same as the spotted snake

    blenny in Greenlandic waters; also reported from Port Burwell, Ungava Bay.

            Lumpenus maculatus (shanny): common along the west coast of Greenland

    from Ivigtut to Jacobshavn; also reported from Port Burwell.

            Lumpenus lampetraeformis (snake blenny): common from Godthaab to Jacobs–

    havn, Greenland.

            Lumpenus medius : rare from Disko Bay north to Northeast Bay, Greenland.



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    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            Lumpenus fabricii : a very common blenny along the west coast of Green–

    land from Nanortalik to Godhavn. Elsewhere it has been recorded from Devon

    Island, Ungava Bay, and Hudson Bay.

            Anarhichas lupus (wolf fish): fairly common from West Greenland to

    Umanak Fjord in the north.

            Anarhichas minor : known from Davis Strait on both sides of the sub–

    marine ridge.

            Anarhichas denticulatus : common in Davis Strait south of the submarine

    ridge.

            Lycodes vahlii ( l e elpout): common in the deep water of Davis Strait.

            Lycodes reticulatus (arctic eelpout): a common eelpout in Davis Strait

    north to Umanak, Greenland; elsewhere reported from Ungava and Hudson Bay.

            Lycodes esmarkii : known from the deep water of Davis Strait.

            Lycodes eudipleurosticus : a common eelpout in the deep cold water of

    Baffin Bay and northwest Greenland.

            Lycodes seminudus : known from Jacobshavn to Upernivik, Greenland.

            Lycodalepis polaris : A widespread range in Arctic America is indicated

    by scattered records from Whale Sou n d, Devon Island, Cumberland Sound, Hudson

    Bay, Point Barrow, and Bering Strait.

            Lycenchelys ingolfianus : known only from the deep water of Davis Strait.

            Gymnelis viridis (fish doctor): a common eelpout throughout the Arctic;

    it has been reported from most stations where collecting has been done.

            Bythites fuscus : Only a single specimen of this fish exists; it was

    collected at Fiskenaes, Greenland.

            Ceratias ho l bölli : uncommon in the deep water of Davis Strait.



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    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

            Oneirodes eschrichtii : rare in the deep water of Davis Strait.

            Himantolophus groenlandicus : very rare in the deep water off Greenland.

           

    Summary

            The Arctic is noted for a paucity of fish fauna. The well-known and

    rich fauna of West Greenland, warmed by Atlantic water, is strongly in con–

    trast to the high-arctic waters of northern Ellesmere Island, where to date

    only two species of fish have been discovered, Salvelinus alpinus and Oncocottus

    quadricornis .

            If the areas whose faunas are influenced by the warming effects of Atlan–

    tic or Pacific water are excluded, the fauna is characterized by relatively

    few families of fish. The common anadromous form which enters most of the

    rivers and streams is the arctic char, a member of the salmon family. Small

    brackish streams are characterized by sticklebacks. Sculpins are represented

    by a variety of species from the shore zone to deep water. Other common mem–

    bers of the shallow and deep zones are the peculiar lumpfish and liparids, or

    sea snails. The eel-like blennies and eelpouts are common in the Laminaria

    zone and deep water. The arctic pollack, a member of the cod family, is the

    most common pelagic form, and is often sighted near the surface among the ice

    floes or in open leads.



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    018      |      Vol_III-0608                                                                                                                  
    EA-Zoo. Hildebrand: Marine Fishes of American Arctic

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