Winter Picoplankton Diversity and Distribution in the US Antarctic Marine Living Resources Study Area - Northern Antarctic Peninsula

Picoplankton (bacteria, archaea, and eukaryotic organisms < 3.0 micron) surveys conducted in collaboration with the U.S. Antarctic Marine Living Resources (AMLR) field research program aimed to study the pelagic ecosystem during month-long winter research cruises in the South Shetland Islands, Scotia Sea and the NW Weddell Sea regions in August, 2012, 2013, and 2014. This inter-annual study on the winter pelagic ecosystem follows a 25-year time series program studying austral summer waters, though is the first survey to also include the characterization of the picoplankton in this study area. The primary goal of the AMLR winter cruise was to establish the ecological importance of winter processes and plankton distributons particularly as related to sea ice and to capture the hydrography and winter distributions of krill for comparisons with summer conditions over this long times series study. The winter time study will help determine how the template for ecological success is set up for summertime production across all trophic levels. The picoplankton research will improve the understanding of winter distributions and provide sample collection opportunities for diversity and biogeochemical studies to create an integrated ecosystem picture that will be developed with the NOAA AMLR group. In particular, this effort will extend the geographic coverage of winter picoplankton in the South Shetland Islands region, both on and off the continental slope. This is important to test hypotheses concerning high latitude winter processes that were observed in coastal Antarctic Peninsula waters suggesting the relative importance of chemolithoautotrophy is a key winter-time metabolic process.