SO-AntEco was a British Antarctic Survey (BAS) led expedition undertaken in conjunction with an international team of scientists from the Scientific Committee for Antarctic Research (SCAR) AntEco research programme. The team included participants from nine different countries and 15 institutes. The expedition took place on board the BAS research ship RRS James Clark Ross in early 2016. The focus of the cruise was to contribute towards a better understanding of selected benthic habitats around the South Orkney Islands, and the biodiversity within those habitats, in relation to the geomorphic zones both inside and outside the South Orkney Islands Southern Shelf (SOISS) Marine Protected Area (MPA). This addresses a key objective set out by the draft SOISS MPA Research and Monitoring Plan (SC-CAMLR, 2014).
The benthic assemblages of the SOISS MPA region were found to be strongly correlated with substrate, where hard substrates hosted a greater number of individuals, taxa and biomass with a dominance of filter feeding Vulnerable Marine Ecosystem (VME) taxa, and soft sediments were dominated mostly by deposit feeders. Substantial differences in the abundance of VME taxa were found between two sampling gears used (shallow underwater camera system and Agassiz trawl). We conclude that camera systems may be more suitable for VME assessments than the Agassiz trawl, but where possible, trawling is advisable for collecting all faunal types and for higher taxonomic resolution. The designation of VME locations or MPAs based purely on geomorphic classification is not advisable, due to small scale variation in substrate and other local physical influences; however, the utility of such classifications may be improved with the inclusion of additional environmental factors e.g. substrate type.
The results from this study will contribute to an updated MPA Report for the South Orkney Islands, as well as the SOISS MPA review scheduled in 2019. In addition, it makes an important contribution to the understanding of benthic habitats in Domain 1, which will be relevant for further spatial planning in this region.