Collaborators: Peter Wiebe (WHOI), Carin Ashjian (WHOI)
The U.S. Southern Ocean GLOBal OCean Ecosystems Dynamics (SO GLOBEC) program examined the physical and biological factors that contribute to the over-wintering success of Antarctic krill in the Marguerite Bay region along the Western Antarctic Peninsula: a key locus of krill abundance hypothesized to be a source for downstream krill populations around South Georgia. During fall- and winter-time surveys in 2001 and 2002, concurrent observations were made of physical processes, nutrient dynamics, primary producers, zooplankton, as well as higher predators, providing an important and unusual opportunity to understand biological-physical linkages at all levels of the ecosystem. More information on the SO GLOBEC program and links to the publications that have appeared to date from the program are available at the program's website.
Within this broader program, we examined the physical processes underlying the distribution and behavior of Antarctic krill and other zooplankton, and, via collaborations with other researchers in the program, the interactions of krill with higher predators, including penguins, seabirds, seals, and cetaceans. This was accomplished using data collected by multi-frequency acoustic, video, net, and environmental sensing systems during broad-scale surveys in and around Marguerite Bay.
The SO GLOBEC program is currently in its synthesis phase, and we continue to explore new facets of the data and to integrate the various multi-disciplinary datasets. In particular, we have ongoing projects examining krill aggregative behavior, via acoustic observations of the morphology, internal structure, and vertical position of individual krill aggregations, in relation to physical and biological factors, including predation threat; and examining the stage-specific distribution of the different euphausiid species in the SO GLOBEC study region.