A DEEPER INSIGHT TO HG BIOACCUMULATION IN THE BAT POPULATION IN KENTUCKY AND TENNESSEE

Mercury (Hg) is a persistent neurotoxin that is readily transported through karst aquifer systems such as the South Central Kentucky Karst (SCKK) ecosystem, which includes Mammoth Cave National Park (MCNP). The largest source of mercury to MCNP is atmospheric deposition, largely produced by coal-fired power plants. Hg from the atmosphere deposits in rivers, sediments, and organisms through rain, wind, and bioaccumulation. Over 350 individual bat hair samples have been analyzed for Hg from MCNP with a wide variety of species diversity. Our project will expand throughout the year to three national parks in Kentucky and Tennessee including Abraham Lincoln, Cumberland Gap, and Big South Fork National Parks. Hg levels in hair of different bat species, including federally listed endangered species have been determined and found to range between 1-13 parts per million (ppm). In addition to bat hair, initial data from approximately 15 bat guano samples have been analyzed for Hg and found to range from 0.0030 ppm to 0.9470 ppm. Further analysis will be performed on insects to gain additional information regarding how bats bioaccumulate Hg through the food chain. Quality analysis and quality control tests were done using human hair reference standards. This multiyear project began in late summer 2002 and will continue through the end of 2008.