Results and standing stock biomass estimates of finfish from the 2001 US AMLR bottom trawl survey of the South Shetland Islands (Subarea 48.1)

The United States Antarctic Marine Living Resources (U.S. AMLR) program conducted a bottom trawl survey in March, 2001 of the South Shetland Islands. Information on species composition, size composition, spatial distribution, and dietary patterns are presented. Estimates of total stock biomass were computed for eight species: Champsocephalus gunnari, Chaenocephalus aceratus, Chionodraco rastrospinosus, Gobionotothen gibberifrons, Lepidonotothen larseni, Lepidonotothen squamifrons, Notothenia coriiceps, and Notothenia rossii. Biomass estimates were compared to the results from the 1998 U.S. AMLR Survey. For most species, the standing stock has decreased slightly, although in most cases the 95% confidence levels from the 2001 surveys were considerably decreased. The results indicate that stocks of N. rossii have not recovered even after commercial fishing has ceased for 20 years. The overall abundance of finfish in the South Shetland Islands has yet to reach a level at which commercial exploitation would be advisable. The potential role of habitat structure in demersal finfish assemblages in the South Shetland Islands is discussed.