New Study Shows Strong Links between Climate and Marine Food Web along Coastal West Antarctic Peninsula

Monday, Jul 7, 2014

Understanding the mechanisms by which climate variability affects multiple trophic levels in food webs is essential for determining ecosystem responses to climate change.  A new study, coauthored by AOS Visiting Research Collaborator Vincent Saba (NOAA National Marine Fisheries Service), uses over two decades of data collected by the Palmer Long Term Ecological Research program (PAL-LTER) to determine how large-scale climate and local physical forcing affect phytoplankton, zooplankton, and an apex predator along the West Antarctic Peninsula (WAP). The authors show that positive anomalies in chlorophyll-a (chl-a) at Palmer Station, occurring every 4-6 years, are constrained by physical processes in the preceding winter/spring and a negative phase of the Southern Annular Mode (SAM). Years of positive chl-a anomalies are associated with the initiation of a robust krill cohort the following summer, which is evident in Adélie penguin diets, thus demonstrating tight trophic coupling. Projected climate change in this region may have a significant, negative impact on phytoplankton biomass, krill recruitment, and upper trophic level predators in this coastal Antarctic ecosystem.   The study, led by Grace Saba (IMCS, Rutgers), was published on July 7 in Nature Communications and is available here.  Related article  Related article