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Abstract SPECIES DIVERSITY AND DISTRIBUTION OF ANTARCTIC AND SUBANTARCTIC CALANOID COPEPODS AS OBSERVED MAINLY IN MID-WATER TRAWL COLLECTIONS (A REVIEW) E. Taisoo Park As far as zooplankton studies are concerned, the Antarctic seas
are among the most intensively investigated regions of the world.
The studies were mainly based on samples collected with plankaton
nets until extensive mid-water trawl collections became available
from the U. S. Antarctic research program. The collections taken
with Isaacs-Kidd midwater trawls throughout the Antarctic and sub-Antarctic
seas that were processed and sorted by the Smithsonian Oceanographic
Sorting Center have provided for the first time sufficient materials
needed for a comprehensive investigation of planktonic organisms
in the entire water column from the surface down close to the bottom.
Based on these samples a number of major studies were made on the
calanoid copepods, the principle constituents of the zooplankton
community, and they are reviewed here to compile a list of species
occurring in the region, determine the distribution range of each
species, and examine their distribution patterns and evolutionary
relationship among the species. The major findings of the review,
either confirming the previous discoveries or representing new findings,
are as follows: The calanoid community in the epipelagic zone (0-200
m) is composed of only a small number of herbivorous species, most
of which are endemic and extremely abundant; the bathypelagic zone
(deeper than 1000 m) harbors a highly diversified community composed
primarily of large, powerful carnivores, many of which are endemics;
the species occurring close to Antarctica are all endemics; the
species ranging across the latitudes show a gradual size increase
toward Antarctica; the common species generally show a circumpolar
distribution; some of the Antarctic species have a counterpart in
the Arctic/sub-Arctic region separated by a great distance of the
tropic and temperate waters. Each of these findings is discussed
in the context of the biology of the Antarctic seas.
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