The wailing calls of the common loon ring out over New York’s Adirondack Park lakes, a treat for birdwatchers who flock to the park. But lately, a more alarming note underscores these mournful calls: the birds face grave threats posed by mercury contamination. Mercury is toxic even in small doses, and it accumulates as it progresses up the food chain. Because loons feed at the highest level of the chain, they cope with heightened risks of exposure.

A new report from WCS, the Biodiversity Research Institute, and the New York State Energy Research and Development Authority indicates that more than half of adult Adirondack loons face medium to high risks of mercury poisoning; it also details the effects produced by such exposure. Adult loons suffering high mercury levels lack good parenting skills: they rarely incubate eggs consistently enough for chicks to hatch, which leads to lower reproductive success for the species.

Zoë Smith, director of WCS’s Adirondack Program, explains, “The long-term survival of loons in the Park will depend on reducing mercury in the atmosphere.”

To read more about mercury poisoning in loons, visit the New York Times.