ISSN 1063-0740, Russian Journal of Marine Biology, 2009, Vol. 35, No. 6, pp. 445–453. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © B.I. Sirenko, 2009, published in Biologiya Morya.
Comparison of the faunas of the two polar oceans—
the Arctic and the Southern Ocean—has long been of
interest to scientists , because this makes it possible
to reveal some general patterns of the distribution of life
on Earth and of the origin of cold-water faunas during
glacial periods. Several such periods have occurred and
the last three of them were in the Late Ordovician, in
the Late Carbon, and in the Quarternary . During
these periods, mass extinctions of species [40, 45–47,
52] and change of faunas occurred in the high latitutes
of both hemispheres.
At ﬁrst glance, the formation of cold-water faunas in
the northern and southern near-polar regions was
caused by similar abiotic environmental factors: nega-
tive temperatures, ice cover and sharply pronounced
seasonality of the duration of the polar day. However,
the formation of the faunas in these regions was sub-
stantially inﬂuenced by the different positions of the
polar oceans (the Arctic Ocean is surrounded on all
sides by land and the Southern Ocean is open on all
sides to three oceans), as well as the different time of
formation of the permanent ice cover: 3000000–
5000000 years ago in the Arctic and 30000000–
35000000 years ago in the Antarctic .
In the present paper, we made an attempt (1) to elu-
cidate the main differences in the species composition
of the faunas of the Arctic and Southern Oceans and (2)
to clarify the reasons for these differences.
MATERIAL AND INFORMATION SOURCES
To compare the marine shelf faunas of the Arctic
and the Antarctic, we selected the seas that are the most
characteristic of each of the oceans under comparison
and that are better studied to date: the Laptev Sea and
the Weddell Sea.
Why are these seas the most typical of the North
Arctic and the Southern Oceans? The Weddell Sea,
when compared with the other Antarctic seas, both
larger ones (the Ross, Bellingshausen, and Common-
wealth Seas) and smaller (the Riiser-Larsen, Davis,
D’Urville, and Amundsen Seas)—mainly differs from
them in its larger size and a more extensive cyclonic
gyre; however, in either points the Weddell Sea little
surpasses the other large Antarctic seas. It is well
known that variously developed cyclonic gyres are
present in all large Antarctic seas and that nearly all the
small seas have currents diverging from the Current of
the Western Winds to Antarctica. The other environ-
mental factors that exist in the Weddell Sea (Table 1)
are the same for all the seas of the Southern Ocean.
As regards the Laptev Sea, the environmental fac-
tors observed in this sea (Table 1) also characterize the
other Arctic seas and the only difference is that of the
varying degree of water freshening by river runoff and
the degree of the inﬂuence of the Atlantic and Paciﬁc
We remember the presence in the Arctic seas of rel-
atively small areas of hard bottoms on the shelf (near
Greenland, Spitsbergen, and Northern Land), which, as
in the Antarctic, are dominated by epibenthic animals.
Main Differences in Macrobenthos and Benthic Communities
of the Arctic and Antarctic, as Illustrated by Comparison
of the Laptev and Weddell Sea Faunas
B. I. Sirenko
Zoological Institute, Russian Academy of Sciences, Saint Petersburg, 199034 Russia
Recceived May 21, 2009
—A comparison of the benthic macrofaunas of the Laptev and Weddell seas revealed considerable dif-
ferences in the species composition of the Arctic and Antarctic shelf faunas. In the Arctic, the infauna has the
highest species diversity and plays the main role in the benthic communities, whereas in the Antarctic the epi-
fauna predominates. The main reasons for these essential differences are (1) the different sediment composition
at the time of formation of cold-water faunas, (2) the different productivity of the ecosystems, (3) the different
extent of exchange with the adjacent oceans, and (4) the different history of the origin of both faunas.
Arctic, Antarctic, Laptev Sea, Weddell Sea, bottom fauna.