Mercury in Fishes from 21 National Parks in the Western United States—Inter- and Intra-Park Variation in Concentrations and Ecological Risk
Monograph or SeriesNumber:
Open-File Report 2014-1051
U.S. Geological Survey
Location of Publication:
Mercury Contamination in Fishes from Western U.S. National Parks Widespread and Variable
Elevated mercury concentrations have been found in aquatic habitats from some of the most pristine and remote parts of the world, including U.S. national parks. In order to better document the extent of contamination, USGS and National Park Service scientists examined mercury concentrations in fish from 86 remote sites across 21 national parks in the western United States. Researchers found substantial variation in fish mercury concentrations among and within parks, suggesting that risk patterns are driven by processes occurring at a combination of scales. Mercury levels in 35 percent of fish were above a benchmark for risk to highly sensitive birds, but only 4 percent of fish exceeded the U.S. EPA criterion for protection of human health. Results indicate that mercury bioaccumulation and risk to aquatic ecosystems of western national parks is widespread, yet highly variable.
Eagles-Smith, C.A., Willacker Jr., J.J., Flanagan, C., 2014, Mercury in Fishes from 21 National Parks in the Western United States—Inter- and Intra-Park Variation in Concentrations and Ecological Risk: U.S. Geological Survey Open-File Report 2014-1051, p. 54.