Loons are long-lived birds at the top of aquatic food webs and are therefore at risk from contaminants that bioaccumulate (increase in concentrations in animals over time) and biomagnify (increase in concentrations as they move up the food web). LPC’s is in the process of analyzing eggs collected from Squam Lake and other lakes around the state to examine the relationship between organic contaminants and common loon reproductive success. Tested eggs have been found to contain elevated levels of PBDE’s (flame retardants), PCB’s (industrial cooling agents), dioxins/furans (byproducts of industrial processes), PFOS (stain repellants), and DDT and chlordane (insecticides). In many cases, these contaminants exceeded lowest observed effects levels (levels known to cause measurable declines in health and/or reproductive success) in other fish-eating birds. LPC is continuing to investigate the levels, effects, and sources of these contaminants in loons to determine the threats they pose to individual loons and loon populations.
Please click here to view our latest contaminant report.