Study Shows Loons’ Reaction to Mercury

The next generation of common loons is being threatened by mercury in the waterfowl’s environment, a U.S. study reports.

An 18-year study by the Wildlife Conservation Society and other organizations found environmental mercury negatively impacts the health and reproductive success of common loons in the U.S. Northeast region, the society said in a news release Tuesday.

The study examined samples of blood, feathers and eggs collected from loons in Maine, New York, New Hampshire, and other states and provinces. Researchers correlated birds’ behavior and levels of methylmercury, the most toxic form of mercury accumulating in the food chain.

Loons with high levels of mercury spent less time at the nest than normal-behaving birds, opening the nest to a higher rate of failure because of eggs chilling or being taken by minks, otters, raccoons and other robbers.

Researchers said loons with high mercury loads also had unevenly sized flight feathers.

This study confirms what we’ve long suspected — mercury from human activities such as coal-burning power plants — is having a significant negative impact on the environment and the health of its most charismatic denizens, and potentially to humans, too, said Nina Schoch of the Wildlife Conservation Society.