Using seabirds to track ecosystem change in the Gulf of Maine

Welch, Linda; Williams, Sara; Langlois, Michael

From the abstract: "For the past 30 years, Maine Coastal Islands NWR, National Audubon Society, and Maine Department of Inland Fisheries and Wildlife have documented annual population levels, productivity rates, diet composition and feeding rates on 11 managed seabird colonies in Maine. While extensive data has been collected at the colonies, we know very little about the at-sea ecology of birds in the Gulf of Maine. While seabird must return to land to raise their young, they spend the majority of their time at sea foraging for themselves and their chicks. As a result, seabirds are intimately linked to physical and biological characteristics of marine ecosystems. Seabirds need persistent aggregations of prey to be located within commuting distance of their breeding colonies. Recently, seabird managers have observed what appear to be significant changes in forage fish abundance and availability for breeding seabirds. Several colonies have abandoned or experienced complete reproductive failure due to lack of available forage fish. We have also observed declines in chick growth and productivity rates. Seabirds are more easily observed, counted, and studied than other marine organisms and changes in ecosystem function will be evident in these upper trophic level predators. We believe that our long-term monitoring efforts at the breeding colonies provide critical evidence that the productivity of the Gulf of Maine has significantly decreased in recent years. We are currently collaborating with several integrated ecosystem based projects to insure that seabirds remain a viable component of the Gulf of Maine ecosystem."