9727077 SMITH The annual expansion and contraction of ice cover in the Southern Ocean is the largest seasonal process in the World Ocean. This seasonal variability in ice cover creates extensive fluctuations in primary production, which heavily impacts pelagic and benthic communities. This research will initiate a long time-series study of the water column and sea floor using long-term, autonomous monitoring and sampling systems developed for use in the Antarctic. The study will be located in Post Foster, Deception Island, which supports a pelagic and benthic fauna representative of the Antarctic coastal zone and experiences seasonal ice cover. A bottom-moored, upward-looking acoustic instrument will be deployed on the sea floor for a period of one year to monitor the vertical distribution, abundance and biomass of acoustically-detectable macrozooplankton and micronekton in the water column. Collections will be made over this period using a newly-developed vertically-profiling pump sampling. Simultaneously, a time-lapse camera system will be moored on the sea floor to monitor the spatial distribution, sizes and movements of the epibenthic megafauna component of the benthic community. The instrumentation development will allow the research project to focus on the effect of the seasonal sea ice cycle on the distribution, abundance and biomass of the macrozooplankton and micronekton in the water column. Similar questions on the distribution, abundance, size and movements of the epibenthic megafauna will be addressed. Results from this study will provide a valuable data base for the evaluation of the pelagic and benthic community responses to seasonal variability in the Southern Ocean.
