The Squam Lake Loon Initiative
Between the fall of 2004 and the spring of 2005, Squam Lake lost seven of its loon pairs. The decline from 19 to 9 pairs represented 44% of Squam’s loon population, a drop unprecedented on Squam or any other large lake in more than 40 years of LPC’s history of monitoring loons throughout New Hampshire. It also brought Squam’s loon population to its lowest level since LPC began to survey Squam Lake in 1975.
Like loons throughout New Hampshire, Squam Lake’s loons face multiple stressors; however, unhatched loon eggs collected by LPC (under state and federal permits) from Squam between 2005 and 2007 revealed high levels of a number of contaminants, including PBDE (flame retardants), PFOS (stain guards), PCB (industrial insulating/cooling agents), and chlordane (a pesticide). Levels of contaminants from Squam eggs during 2005-2007 were two to nine times higher than levels found in eggs collected from the other lakes. Our knowledge of the effects of these contaminants, especially combinations of contaminants, on loons is limited. However, some of these contaminants were present in loon eggs at levels that have been shown to affect the physiology, health, and/or reproductive success of other bird species.