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File A regional neural network ensemble for predicting mean daily river water temperature
Water temperature is a fundamental property of river habitat and often a key aspect of river resource management, but measurements to characterize thermal regimes are not available for most streams and rivers. As such, we developed an artificial neural network (ANN) ensemble model to predict mean daily water temperature in 197,402 individual stream reaches during the warm season (May–October) throughout the native range of brook trout Salvelinus fontinalis in the eastern U.S. We compared four models with different groups of predictors to determine how well water temperature could be predicted by climatic, landform, and land cover attributes, and used the median prediction from an ensemble of 100 ANNs as our final prediction for each model. The final model included air temperature, landform attributes and forested land cover and predicted mean daily water temperatures with moderate accuracy as determined by root mean squared error (RMSE) at 886 training sites with data from 1980 to 2009 (RMSE = 1.91 C). Based on validation at 96 sites (RMSE = 1.82) and separately for data from 2010 (RMSE = 1.93), a year with relatively warmer conditions, the model was able to generalize to new stream reaches and years. The most important predictors were mean daily air temperature, prior 7 day mean air temperature, and network catchment area according to sensitivity analyses. Forest land cover at both riparian and catchment extents had relatively weak but clear negative effects. Predicted daily water temperature averaged for the month of July matched expected spatial trends with cooler temperatures in headwaters and at higher elevations and latitudes. Our ANN ensemble is unique in predicting daily temperatures throughout a large region, while other regional efforts have predicted at relatively coarse time steps. The model may prove a useful tool for predicting water temperatures in sampled and unsampled rivers under current conditions and future projections of climate and land use changes, thereby providing information that is valuable to management of river ecosystems and biota such as brook trout.
Located in Science and Data / Brook Trout Related Publications
Aaron Run (MD) - Mitigating Acid Mine Drainage Improves pH Levels in Run
Waterbody Improved: water flowing through abandoned coal mines contributed acid mine drainage (AMD) to Maryland’s Aaron Run, causing the stream’s pH level to fail to meet the state’s water quality standard for pH. As a result, the Maryland Department of the Environment (MDE) added Aaron Run to Maryland’s 2004 Clean Water Act (CWA) section 303(d) list of impaired waters for low pH. Watershed partners implemented numerous AMD mitigation projects, and pH levels increased. Aaron Run now meets the state water quality standard for pH and supports a population of brook trout. As a result, MDE has proposed removing Aaron Run from the state’s list of impaired waters for pH impairment in 2014.
Located in News & Events / News Inbox
File Acid Mine Drainage and Effects on Fish Health and Ecology: A Review
Acid rock drainage (ARD) is produced by the oxidation of sulfide minerals, chiefly iron pyrite or iron disulfide (FeS2). This is a natural chemical reaction which can proceed when minerals are exposed to air and water. Acidic drainage is found around the world both as a result of naturally occurring processes and activities associated with land disturbances, such as highway construction and mining where acid-forming minerals are exposed at the surface of the earth. These acidic conditions can cause metals in geologic materials to dissolve, which can lead to impairment of water quality when acidic and used by terrestrial or aquatic organisms. metal laden discharges enter waters.
Located in Science and Data / Brook Trout Related Publications
File An Assessment of the EBTJV’s Project Ranking Criteria Alignment with the National Fish Habitat Board’s Minimum Benchmark Set of Project Prioritization Criteria (2013)
The National Fish Habitat Board (Board) adopted a minimum benchmark set of fish habitat conservation project prioritization criteria at their February, 2013 meeting. These criteria are intended to ensure core tenets of the National Fish Habitat Action Plan are considered by Fish Habitat Partnership when ranking projects for funding. To ensure criteria the Eastern Brook Trout Joint Venture (EBTJV) uses to rank proposed fish habitat conservation projects are strongly aligned with the Board’s minimum benchmark set of project prioritization criteria, an assessment was undertaken and the outcome of that assessment is described in this document.
Located in Projects / EBTJV Operational Evaluation Reports
File An Economic Analysis of Improved Road‐Stream Crossings
Road‐stream crossings, which include culverts and bridges, are an essential element of our transportation networks, allowing roads to pass over rivers and streams. Our communities and our economies depend on functioning road networks and safe crossings. We also depend on healthy rivers and streams for clean water, recreation, and a host of other benefits, and we are learning more about the relationships between road‐stream crossing designs and their effect on natural areas. Undersized or poorly designed crossings fragment streams and disrupt the natural movement of water, sediment and aquatic organisms, causing erosion and degraded habitat. The most problematic of these crossings prevent aquatic organisms, such as brook trout, from accessing the upstream habitat they need to survive and reproduce. Yet crossings can be designed to avoid these problems. Improved road‐stream crossings deliver social, economic and ecological benefits and are a key element of adapting our infrastructure to a changing climate. Unfortunately, their initial cost can be a significant obstacle for highway departments with limited budgets.
Located in Science and Data / Brook Trout Related Publications
File An Overview of Brook Trout Conservation Projects Supported by U.S. Fish and Wildlife Service National Fish Habitat Action Plan Funds, 2006-2018
This report provides an overview of Brook Trout conservation projects supported by FWS-NFHAP funds from 2006-2018.
Located in Science and Data / EBTJV Reports
File An Overview of EBTJV Brook Trout Conservation Projects, 2006-2018
This report summarizes EBTJV Brook Trout conservation projects that received FWS-NFHAP funding from 2006 through 2018.
Located in Projects / EBTJV Operational Evaluation Reports / Accomplishment Summaries
File ECMAScript program An updated geographic distribution of Myxobolus cerebralis (Hofer, 1903) (Bivalvulida: Myxobolidae) and the first diagnosed case of whirling disease in wild-caught trout in the south-eastern United States
Myxobolus cerebralis (Bivalvulida: Myxobolidae), the aetiological agent of salmonid whirling disease, was detected in 2 river basins of North Carolina during 2015, which initiated the largest spatial–temporal monitoring project for the disease ever conducted within the south-eastern United States (focused mainly in eastern Tennessee and western North Carolina). A total of 2072 rainbow trout Oncorhynchus mykiss, 1,004 brown trout Salmo trutta and 468 brook trout Salvelinus fontinalis were screened from 113 localities within 7 river basins during June 2017 through October 2019. Infections were detected by pepsin–trypsin digest, microscopy and the species-specific nested polymerase chain reaction (PCR) in 19 localities across 6 river basins. Myxospore morphology was indistinguishable from the published literature. In 2019, five rainbow trout that symptomatic for whirling disease (sloping neurocranium and lordosis) were captured and processed for histopathology. Myxospores were detected in the calvarial cartilage of two deformed trout with associated erosion of the cartilage consistent with reported whirling disease lesions. This is the first report of M. cerebralis in Tennessee and the first histologically confirmed cases of whirling disease in southern Appalachian (south-eastern United States) rivers and streams and expands the distribution of M. cerebralis throughout western North Carolina and eastern Tennessee.
Located in Science and Data / Brook Trout Related Publications
File Troff document Anthony Creek & Little Cataloochee Creek Restoration, TN/NC_FY17 Project
In Anthony Creek and Cataloochee Creek, non-native Rainbow Trout were removed from 2.8 km (1.75 mi) and 6.4 km (4.0 mi) stretches of stream, respectively; native Brook Trout were collected from streams within Great Smoky Mountains National Park and release them into both creeks; and, Brook Trout populations were monitored in during subsequent years to determine success of this project.
Located in Projects / Project Completion Reports
File Appendix I - Catchment Assessment Summary Report
This is a master copy of the catchment assessment data.
Located in Science and Data / Data and Brook Trout Decision Support Tools / Brook Trout Catchment Assessment Summary Report and Appendix Tables