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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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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 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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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.
Ecological assessments are a central focus of multidisciplinary projects and programs managed by the NYWSC and managed in cooperation with the water and soil chemistry laboratory as well as other Federal, State, county, and city agencies, academia, and nongovernmental organizations in New York and nationwide. The NYWSC studies the condition of aquatic communities to assess the effects of various manmade and natural stressors and of resource management practices on the aquatic ecosystems and environments in the State and nationwide and in cooperation with a wide array of partners and monitors climate change indicators to identify trends and data gaps for indicators of climate and habitat change. Specific studies...
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Problem: The Clean Water Act (PL 92-500) requires that the health of the Nation’s rivers and streams be assessed on a regular basis, and in the Northeast such assessments often use information from aquatic biological communities that live in the stream. Biomonitoring programs implemented by individual states evaluate biological data to assess stream health on the premise that certain sensitive species that are native to the region cannot survive when water quality is poor. The aquatic community data are typically condensed into a set of biological condition metrics that are scaled numerically to convey the relative degree of stream impairment (e.g., excellent, good, fair, poor). However, biological condition...
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A. BACKGROUND Aquatic macroinvertebrates, such as dragonfly larvae or crayfish have great potential for Mercury (Hg) monitoring, both as indicator organisms (or "sentinels'), and to provide critical information on Hg in lower food webs to assist in interpreting fish Hg levels. Despite these advantages, macroinvertebrates are not widely used in Hg monitoring because of the current need to directly analyze macoinvertebrate tissue for methyl-mercury (MeHg), at much greater expense than analyzing for total Hg (THg) (i.e. as a surrogate for MeHg), as with fish tissue. This is because the ratio of MeHg to THg in macroinvertebrates exhibits large taxonomic, spatial, and temporal variation, and there is no clear...
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The Catskill Mountains of southeastern New York receive among the highest loads of acid deposition in New York and the northeastern U.S. Additionally, the Catskills are underlain by sandstone and conglomerate, which is base poor and weathers slowly. Thus, the Catskills contain numerous streams with low (< 50 µeq/L) acid-neutralizing capacity (ANC) and are sensitive to impacts from atmospheric acid deposition. Since at least 1983, however, the levels of acidity in atmospheric deposition (primarily sulfuric acid) have been declining in the Catskills and throughout New York. While widespread recovery of streams in the Catskills has not yet been confirmed, recent data suggest that recovery in waters with ANC values...
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BackgroundDetailed investigations of mercury cycling and bioaccumulation have been done in the Upper Hudson River basin (upstream of the Hudson River near Newcomb, in New York's Adirondack Mountains, with a focus on the Fishing Brook sub-basin, part of the western headwaters of the Hudson River. This study is part of a National mercury study that includes a concurrent study of McTier Creek, a headwater sub-basin of the Edisto River, located in South Carolina's Coastal Plain. These two study areas provide contrasting and complementary settings for the study of mercury cycling and bioaccumulation in headwater streams with close connectivity to out-of-channel wetlands. Atmospheric deposition is the dominant source...


    map background search result map search result map Potential Recovery of Water Chemistry and Stream Biota from Reduced Levels of Acid Deposition at a Sensitive Watershed in the Catskill Mountains, New York The Effects of Watershed and Stream Liming on Mercury Dynamics at Honnedaga Lake Mercury Cycling and Bioaccumulation in the Upper Hudson River Basin--Fishing Brook The Effectiveness of Total Mercury as a Surrogate for Methylmercury in Aquatic Invertebrates Effects of flow alteration on ecological health of streams across the Atlantic Highlands Ecoregion Mercury Bioaccumulation in Fish in New York's Streams and Rivers Large River Monitoring Forum (LRMF) Chemical and Physical Controls on Mercury Source Signatures in Stream Fish from the Northeastern United States Methylmercury and associated data in macroinvertebrates from tributaries of Honnedaga Lake and from the Middle Branch Black River in New York. The Effects of Watershed and Stream Liming on Mercury Dynamics at Honnedaga Lake Potential Recovery of Water Chemistry and Stream Biota from Reduced Levels of Acid Deposition at a Sensitive Watershed in the Catskill Mountains, New York Methylmercury and associated data in macroinvertebrates from tributaries of Honnedaga Lake and from the Middle Branch Black River in New York. Chemical and Physical Controls on Mercury Source Signatures in Stream Fish from the Northeastern United States Mercury Bioaccumulation in Fish in New York's Streams and Rivers Effects of flow alteration on ecological health of streams across the Atlantic Highlands Ecoregion Large River Monitoring Forum (LRMF) Mercury Cycling and Bioaccumulation in the Upper Hudson River Basin--Fishing Brook The Effectiveness of Total Mercury as a Surrogate for Methylmercury in Aquatic Invertebrates