Distribution and diversity of polychaetes collected by trawling in Admiralty Bay: an Antarctic glacial fiord

The aim of the study is to determine patterns of distribution, species richness and diversity of polychaetes collected by trawling in Admiralty Bay. Forty-seven species of polychaetes were found in 75 samples collected in 1988 along a depth range from 15 to 500 m. Four polychaete assemblages were distinguished. The most diverse and peculiar assemblage was found in the deepest sublittoral of the central basin from ca. 300-500 m with main constant species Laetmonice producta, Sternaspis sp. and Thelepus cincinnatus. Shallow water assemblages had low diversity and species richness. The most common and eurytopic epifaunal polychaetes were Aglaophamus trissophyllus, Barrukia cristata, Harmothoe spp., Flabelligera mundata and Perkinsiana littoralis. The low species richness in shallow waters of Admiralty Bay is probably associated with depth, influence of glacial streams and suspended matter inflow which is particularly distinct in the shallow water fiord areas.