Reduced productivity has been documented in fish‐eating birds inhabiting Androscoggin Lake in west‐central Maine. The cause of reduced productivity of fish‐eating birds at Androscoggin Lake is not known and could be related to changes in habitat (e.g., loss of nest trees or flooding), predation, harassment or other disturbances during breeding seasons, or to environmental contaminants. Dead Stream connects Androscoggin Lake to the Androscoggin River and during high flows the river will flood into the lake. Three pulp and paper mills existed on the Androscoggin River upstream from Androscoggin Lake. Previous bio‐monitoring studies by the Maine Department of Environmental Protection found elevated concentrations of organic contaminants in fish tissue from Androscoggin Lake and the Androscoggin River. To determine if organochlorine compounds were accumulating and affecting productivity of fish‐eating birds, non‐viable eggs of bald eagles (n = 14) and common loons (n = 8) were collected from Androscoggin Lake and the Androscoggin River watershed between 2001 and 2009. Bald eagle eggs from the Penobscot River watershed (n = 19) and common loon eggs from the Kennebec River watershed (n = 2) were collected for comparative purposes. Eggs were analyzed for dioxins and furans, polychlorinated biphenyl (PCB), DDT metabolites, and other organochlorine compounds. Concentrations were expressed on a fresh wet weight basis. Analytical results for each species were compared between watersheds and to suggested avian egg toxicity threshold levels.
