Climate change disrupting base of Antarctic food web

As the cold, dry climate of the western Antarctic Peninsula becomes warmer and more humid, phytoplankton – the bottom of the Antarctic food chain – is decreasing off the northern part the peninsula and increasing further south, Rutgers marine scientists have discovered. In research to be published tomorrow in the journal Science, Martin Montes-Hugo and Oscar Schofield report that levels of phytoplankton off the western Antarctic Peninsula have decreased 12 percent over the past 30 years. Their paper, “Recent Changes in Phytoplankton Communities Associated with Rapid Regional Climate Change Along the Western Antarctic Peninsula,” draws on 30 years of satellite data and field studies. … "What is new is that we’re showing for the first time that there is an ongoing change on phytoplankton concentration and composition along the western shelf of the Antarctic Peninsula that is associated with a long-term climate modification," Montes-Hugo said. "These phytoplankton changes may explain in part the observed decline of some penguin populations" Researchers have noticed that populations of adelie penguins, whose lifestyle requires an Antarctic climate, have dropped sharply in recent years in the northern part of the peninsula, while populations of sub-Antarctic penguins, such as chin-strap penguins, have increased. "Now we know that climate changes are impacting at the base of the food web and forcing their effects on up through the food chain," said Hugh Ducklow, co-author of the paper and co-director of the Ecosystems Center at the Marine Biological Laboratory in Woods Hole, Massachusetts. …