The Antarctic Peninsula supports the most abundant and diverse populations of plants and animals on the continent. The grounding of the supply ship Bahia Paraiso and subsequent oil spill near the U.S. Palmer Station significantly impacted the area. Initial observations have revealed that the oil has coated macroalgae and invertebrates living on the hard substrata along intertidal cobble beaches and in tidal pools. Many of the invertebrates, which form the base of the Antarctic food web, have been killed. The oil has also affected seals and birds. Some of the oiled birds have died and others have shown symptoms of starvation, adverse behavior and loss of insulation. This research project is part of an integrated, time-series survey of the marine environment in the vicinity of the oil spill. The research groups will examine the spatial and temporal extent of the oil contamination and the associated effects on marine flora and fauna. This project will focus on macroalgae physiology. In addition, plant and animal samples will be collected for the analysis of stable carbon and nitrogen isotopes in order to determine food web structure in control and affected sites.