A loon chick is held while researchers from the Biodiversity Research Institute draw a blood sample, weigh it, and put identification bands on its leg on Rangeley Lake in Rangeley, Maine, August 22, 2005. Researchers test the blood sample to monitor mercury levels in the lake caused by fallout of pollution from the mid-western United States. Picture taken August 22, 2005. TO ACCOMPANY FEATURE ENVIRONMENT MERCURY REUTERS/Brian Snyder BS./DY