Antarctic Science 14 zyxwvutsr (I), 3-10 zyxwvutsr (2002) @AntarcticScience Ltd Printed in the United Kingdom zyx Composition and distribution of suprabenthic fauna in the south- eastern Weddell Sea and off King George Island KATRIN LINSE*, ANGELIKA BRANDT, BRIGITTE HlLBlG and GlSELA WEGENER Zoologicai Institute and Museum, University of Hamburg, Martin-Luther-King-Pfatz 3,0-20146 Hamburg, Germany *present address. British Antarctic Survey, High Cross, Madingley Road, Cambridge CB3 OET, zyx UK zyx Abstract: Composition, abundance, and distribution of suprabenthos froma depth between 1 and 1.33 mabove the seafloor were analysed. The samples were taken during ANT XVl3 with RV Polarstern in February and March 1998 by means of the supranet of an epibenthic sledge along two transects in the southern Weddell Sea (Vestkapp and Halley Bay) and one east of King George Island. At each of these three transects, five to six stations were taken in water depth between 200 and 2000 m. In total, 34 057 specimens were sampled at 16 stations, yielding 1 205 050 individuals for all stations standardized to 1000 m3 hauls. Of these, copepods were usually the most abundant group in the supranet (805 822 ind 1000 m-9. The suprabenthic fauna of the south- west of Vestkapp (Weddell Sea) transect was dominated by planktonic taxa in terms of individual numbers especially at the deeper stations (938-1983 m). At Halley Bay the total abundance ofplankton was lower but its relative abundance zyxwvuts (> 80%) was also high, whilst off King George Island peracarid crustaceans were an important fraction. Received 6 November 2000, accepted 17 November 2001 Key words: Antarctica, composition, Copepoda, distribution, suprabenthos Introduction Ourknowledge ofthe composition and distributionofhtarctic suprabenthic communities is still negligible. San Vincente et al. (1997) published first results on the composition and vertical distribution of suprabenthic assemblages from the South Shetland Islands and the Bransfield Strait, Siege1 & Miihlenhardt-Siegel( 1988)described the occurrenceofmysids in the Antarctic Peninsula region and Brandt (2001) showed great differences in peracarid crustacean density between Arctic and Antarctic. Further studies have been scarce. In other parts of the world's oceans the knowledge on suprabenthic communitieshas increased slightlyduring recent years. Especially in the north-east Atlantic, comprehensive studies were done in the Norwegian Sea (FossH & Brattegard 1990, Buhl-Jensen & Fossd 1991), in the Bay of Biscay (e.g. Comet et al. 1983, Sorbe 1989, Elizalde et al. 1991, Dauvin & Sorbe 1995) and on the Portuguese continental margin (Cunha et al. 1997). These studies, however, focussedmainly on the shallow locations while first observations on deep-sea suprabenthos were made by Wishner (1 980) in the tropical east Pacific, Red Sea and north-east Atlantic and in the Arctic Ocean by Brandt & Barthel(1995), Brandt et al. (1996), and Sirenko et al. (1996). The present study is based on material taken by means of an epibenthic sledge(Brandt&Barthe11995) duringtheEASIZI1 Programme ofthe RV Polarstern ANT XVl3 expedition to the Weddell Sea and South Shetland Islands from January to March 1998. The objectives of this study are 1) to analyse the abundance, composition and species richness ofthe suprabenthicfauna offVestkapp (73*30S, 3 22"20'W), off Halley Bay (74"30'S, 27"OO'W) (both Weddell Sea), andoffKing George Island(SouthShet1and Islands) (62"20'S, 58"30'W), 2) to describe their distribution on the continental slope from 200-2000 m depth, 3) to comparethe suprabenthic faunabetweenthese transects, and zyxw 4) to compare these data with data on the abundance and species richness of suprabenthic taxa, especially of peracarid taxa, taken with the same gear in the Arctic Ocean (Brandt I995,1997a, 1997b, Brandt et al. 1996) at similar depths. This is the first suprabenthic community analysis of the benthic nepheloid layer ofhigh Antarctic waters and will serve as a baseline for future investigations on this subject. Results of these investigations are of importance for many disciplines, including ecological studies. A rich benthic nepheloid layer fauna indicates high food availability (in terms of chlorophyll equivalents) and very probably also influences the benthic fauna - especially predators - as another potential food source. Study area Three transects from shallow to deep water were taken: two in the eastern Weddell Sea south-west of Vestkapp and off Halley Bay and one off King George Island in the Bransfield Strait (Fig. 1). The following depth levels were sampled: https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0954102002000512 Downloaded from https://www.cambridge.org/core. IP address: 207.241.231.80, on 25 Jul 2018 at 08:29:14, subject to the Cambridge Core terms of use, available at