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.