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David M Walters

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This data release includes mercury concentrations and mercury stable isotope measurements measured in sediments and biological tissues collected from the Saint Louis River located in Minnesota. Sediments and biota were collected by the U.S. Geological Survey, U.S. Environmental Protection Agency, U.S. Army Corps of Engineers, and federal contractors (Battelle) from 2017-2021. Collection regions included nearshore zones within the main estuary, remedial sites within the lower river, and upstream reservoir sites. Sediments were analyzed for total mercury, methylmercury, and mercury stable isotopes by the U.S. Geological Survey Mercury Research Laboratory (MRL, Madison, Wisconsin). Biological samples were analyzed...
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Native trout in the West suffer a high degree of vulnerability, as highlighted by cutthroat trout, a group of 14 subspecies, most of which have been petitioned for listing under the Endangered Species Act (ESA). In the Southern Rocky Mountains, greenback cutthroat trout (Oncorhynchus clarkii stomias; GBCT) are listed as threatened under the ESA, and few populations remain, in part because of the invasion of nonnative fishes (for example, brook trout, Salvelinus fontinalis). In an effort to restore GBCT to their native range, chemical treatments (piscicides) are often used as a tool to remove nonnative fishes prior to reintroducing native fish. However, the influence of the piscicides on nontarget organisms, such...
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