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Karen R Murray

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Macroinvertebrate samples were collected from streams tributary to Honnedaga Lake and from the Middle Branch of the Black River during 2012-2016 and analyzed for methylmercury concentrations and for stable isotope ratios of nitrogen and carbon. Macroinvertebrates were identified in the field, and the level of taxonomic resolution varied from order to species; most taxa were identified to the family level. Specimens were field-processed into composite samples, field-frozen, and submitted to the mercury laboratory for freeze-drying and analysis. Subsamples were then submitted to the stable isotope laboratory for analysis of nitrogen and carbon isotope ratios. This database contains the resulting data and associated...
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Problem The Adirondack region of New York has 128 lakes that are listed as impaired by acidity under section 303(d) of the Clean Water Act. Acidity can limit the survival and reproduction of native fishes such as brook trout (Salvelinus fontinalis). Chronic and episodic acidification also stresses fish, aquatic macroinvertebrates, and other biota of inflowing tributaries of these and many additional lakes. Acidification of these tributaries can also affect the health of fish populations in receiving lakes, by limiting suitable spawning and nursery habitat. Although many Adirondack lakes have shown decreased acidity resulting from decreases in atmospheric sulfur and nitrogen emissions, the ecological improvements...
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The Northeast Stream Quality Assessment (NESQA) performed mercury (Hg) isotope analysis of prey fish, game fish, and sediments from 29 sites across an urban to forested land-use gradient. The data presented here includes the chemical analysis of Hg concentrations and isotopes, capture information for fish species, land use, and stream water quality variables. Using these parameters it was determined that the preservation of Hg isotope signatures, which are indicative of source (e.g. atmospheric deposition, industrial point discharge), were dependent on land use, proximity to point sources, and variables related urbanization (e.g. road density and impervious surface cover). Additional Information regarding the interpretation...
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Background Although New York State has more than 70,000 miles of streams and rivers, little is known about the status, distribution, and trends of mercury (Hg) levels in stream fish, or the environmental drivers of these patterns. Streams and their riparian zones provide critical habitat for fish, birds, mammals, reptiles and amphibians, and serve as the interface between aquatic and terrestrial Hg transfer, transformations (most notably methylation) and bioaccumulation. Importantly, monitoring data from lakes (e.g., Simonin et al. 2006) does not transfer reliably to streams because of fundamental differences in Hg cycling and bioaccumulation processes. An assessment of fish Hg bioaccumulation focused on New...
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The Large River Monitoring Forum focuses on fish, fish habitat research, and monitoring approaches, including: scientific objectives for comparisons within and among aquatic ecosystems; scientifically sound monitoring design; methods for data collection and analysis; and best practices for data and information management. This forum enhances agency capacity by sustaining collaboration among USGS expert staff as well as provide opportunity for collaborating agencies and tribes to contribute to the development of recommendations for the implementation of a national network.
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