UNDER-ICE DAILY MIGRATION OF ANTARCTIC CO PEPODS

Daily vertical migration of copepods in the ice-covered western part o f the Weddell Sea has been studied. Sea ice was about 2 m thick with 0 .5 m snow cover. Medium depth habitation of Metridia gerlachei (female ) varied from 53 m at night to 175 m at day time Coppepodits V of Cala noides acutus performed inverted migration with lesser depth range: th ey migrated from 198 m at night to 258 m at day time. Data for M. gerl achei vertical migration in ice covered and ice free areas of the Wedd ell Sea were compared. It was shown that in the ice free area the medi um depth of M. gerlachei was 47 m deeper than in the ice covered area, but the range of migration was greater - 46 m. Day and night depths o f occurence of M. gerlachei are not related with the levels of underwa ter illumination.