Skip to main content
U.S. flag

An official website of the United States government

Nathaniel (Than) Hitt, PhD

Dr. Nathaniel (Than) P. Hitt is a Research Fish Biologist at the USGS Eastern Ecological Science Center in Kearneysville, West Virginia

He holds a B.A. in Biology from the College of Wooster, an M.S. in Organismal Biology and Ecology from the University of Montana, and a Ph.D. in Fisheries and Wildlife Sciences from Virginia Tech. Dr. Hitt’s research investigates freshwater fish ecology from a landscape perspective, focusing on stream ecosystems in the Appalachian highlands.  His research includes:

  • Modeling fish habitat and population/community responses to environmental change
  • Forecasting effects of climate change for fish habitat in headwater streams
  • Effects of stream flow and temperature on fish population dynamics
  • Optimizing conservation and restoration planning for native fishes 

Professional Experience

  • 2009-present: Research Fish Biologist, US Geological Survey, Eastern Ecological Science Center

  • 2015-present: Adjunct Associate Professor, Department of Ecosystem Science and Management, Pennsylvania State University

  • 2008-2009: Postdoctoral Researcher, US Geological Survey, Leetown Science Center

  • 2007-2008: Postdoctoral Researcher, Virginia Tech, Department of Fisheries and Wildlife Sciences

  • 2007-2008: Postdoctoral Researcher, Virginia Tech, Department of Fisheries and Wildlife Sciences 

  • 1999-2002: Graduate Research Assistant, University of Montana, Division of Biological Sciences  

Education and Certifications

  • 2007 PhD, Virginia Polytechnic Institute and State University, Blacksburg, VA, Department of Fisheries and Wildlife Sciences 

  • 2002 MS, University of Montana, Missoula, MT, Division of Biological Sciences, Organismal Biology and Ecology

  • 1996 BA, The College of Wooster, Wooster, OH  Biology, Honors

Science and Products

Filter Total Items: 15
link
A green sunfish

Study reveals importance of groundwater for stability of freshwater fish populations and resilience to climate change

Issue: Climate change is warming streams and rivers of the Chesapeake Bay watershed, and this is a critical concern for fisheries management and conservation. To address this issue, the Chesapeake Bay Program (CBP) recently identified four actions: • address the threats of climate change in all aspects of the partnership’s work; • prioritize communities, working lands, and most vulnerable habitats...
By
Chesapeake Bay Activities, Eastern Ecological Science Center
link

Study reveals importance of groundwater for stability of freshwater fish populations and resilience to climate change

Issue: Climate change is warming streams and rivers of the Chesapeake Bay watershed, and this is a critical concern for fisheries management and conservation. To address this issue, the Chesapeake Bay Program (CBP) recently identified four actions: • address the threats of climate change in all aspects of the partnership’s work; • prioritize communities, working lands, and most vulnerable habitats...
Learn More
link
Brook trout image

Brook trout vulnerability to drought: eastern component of USGS national integrated ecohydrological research

There is a growing and urgent need to develop and implement innovative strategies to research, monitor, and manage freshwater resources as societal demands escalate simultaneously with climate-driven changes in water availability.
By
Ecosystems Mission Area, Species Management Research Program, Eastern Ecological Science Center
link

Brook trout vulnerability to drought: eastern component of USGS national integrated ecohydrological research

There is a growing and urgent need to develop and implement innovative strategies to research, monitor, and manage freshwater resources as societal demands escalate simultaneously with climate-driven changes in water availability.
Learn More
link
Image Collage of Landsat, pollinator, and volcanologist

Study of stream fishes provides new framework to monitor climate change in the Chesapeake Bay headwaters

Issue: The Chesapeake Bay Program (CBP) have identified four goals for actions toward change climate: • address the threats of climate change in all aspects of the partnership’s work; • prioritize communities, working lands, and most vulnerable habitats; • apply the best scientific, modeling, monitoring and planning capabilities; and • connect restoration outcomes with emerging opportunities. A...
By
Chesapeake Bay Activities
link

Study of stream fishes provides new framework to monitor climate change in the Chesapeake Bay headwaters

Issue: The Chesapeake Bay Program (CBP) have identified four goals for actions toward change climate: • address the threats of climate change in all aspects of the partnership’s work; • prioritize communities, working lands, and most vulnerable habitats; • apply the best scientific, modeling, monitoring and planning capabilities; and • connect restoration outcomes with emerging opportunities. A...
Learn More
link
brook trout

Enabling AI for citizen science in fish biology

Artificial Intelligence (AI) is revolutionizing ecology and conservation by enabling species recognition from photos and videos. Our project evaluates the capacity to expand AI for individual fish recognition for population assessment. The success of this effort would facilitate fisheries analysis at an unprecedented scale by engaging anglers and citizen scientists in imagery collection. This...
By
Core Science Systems Mission Area, Ecosystems Mission Area, Species Management Research Program, Eastern Ecological Science Center
link

Enabling AI for citizen science in fish biology

Artificial Intelligence (AI) is revolutionizing ecology and conservation by enabling species recognition from photos and videos. Our project evaluates the capacity to expand AI for individual fish recognition for population assessment. The success of this effort would facilitate fisheries analysis at an unprecedented scale by engaging anglers and citizen scientists in imagery collection. This...
Learn More
link
Brook trout

Effects of introduced species on native brook trout: a guide to the scientific literature

Issue: Native brook trout (Salvelinus fontinalis) are of great ecological, cultural, and economic importance in eastern North America, and their restoration is a focus of the Chesapeake Bay Program. Introduced, non-native species can jeopardize native brook trout, and more information on these effects are needed.
By
Core Science Systems Mission Area, Chesapeake Bay Activities
link

Effects of introduced species on native brook trout: a guide to the scientific literature

Issue: Native brook trout (Salvelinus fontinalis) are of great ecological, cultural, and economic importance in eastern North America, and their restoration is a focus of the Chesapeake Bay Program. Introduced, non-native species can jeopardize native brook trout, and more information on these effects are needed.
Learn More
link
USGS science for a changing world logo

Enabling AI for citizen science in fish ecology

Artificial Intelligence (AI) is revolutionizing ecology and conservation by enabling species recognition from photos and videos. Our project evaluates the capacity to expand AI for individual fish recognition for population assessment. The success of this effort would facilitate fisheries analysis at an unprecedented scale by engaging anglers and citizen scientists in imagery collection.This proje
By
Community for Data Integration (CDI)
link

Enabling AI for citizen science in fish ecology

Artificial Intelligence (AI) is revolutionizing ecology and conservation by enabling species recognition from photos and videos. Our project evaluates the capacity to expand AI for individual fish recognition for population assessment. The success of this effort would facilitate fisheries analysis at an unprecedented scale by engaging anglers and citizen scientists in imagery collection.This proje
Learn More
link
Dr. Kent Crawford lifts a carp caught during a 2015 electro-fishing survey for Smallmouth Bass on the Conodoguinet Creek.

Changing Freshwater Flows Affect Fish Populations in the Potomac River

Issue: Millions of people rely on the Potomac River for drinking water and recreational opportunities. The Potomac is Maryland’s most popular freshwater fishing destination, and the second largest river that enters the Chesapeake Bay. Restoring fisheries is also an important goal for the Chesapeake Bay Partnership restoration efforts.
By
Core Science Systems Mission Area, Chesapeake Bay Activities
link

Changing Freshwater Flows Affect Fish Populations in the Potomac River

Issue: Millions of people rely on the Potomac River for drinking water and recreational opportunities. The Potomac is Maryland’s most popular freshwater fishing destination, and the second largest river that enters the Chesapeake Bay. Restoring fisheries is also an important goal for the Chesapeake Bay Partnership restoration efforts.
Learn More
link
A bright red underbelly of a trout is shown as the fish is swimming in a shallow rocky stream.

Brook Trout Population Responses to Climate Variation Across the Southeast USA

Brook trout are the only native fish from the salmon family in the southeastern United States. Despite their recreational and cultural significance, human activities, such as habitat degradation and introduction of non-native species, have led to serious declines of brook trout populations in the region. Stream temperature and flow alterations from climate change are projected to impact this cold-
By
Climate Adaptation Science Centers
link

Brook Trout Population Responses to Climate Variation Across the Southeast USA

Brook trout are the only native fish from the salmon family in the southeastern United States. Despite their recreational and cultural significance, human activities, such as habitat degradation and introduction of non-native species, have led to serious declines of brook trout populations in the region. Stream temperature and flow alterations from climate change are projected to impact this cold-
Learn More
link
Blue Ridge Sculpin

Restoring a native fish to Catoctin Mountain Park

Native species conservation is a fundamental purpose of National Parks. Catoctin Mountain Park (CATO) in Maryland supports a prized trout fishery and a healthy community of native fishes, with one exception: native Blue Ridge Sculpin (Cottus caeruleomentum) appear to have been extirpated from Big Hunting Creek above Cunningham Falls. Infection by a fungal-like protist Dermocystidium is...
By
Ecosystems Mission Area, Species Management Research Program, Eastern Ecological Science Center
link

Restoring a native fish to Catoctin Mountain Park

Native species conservation is a fundamental purpose of National Parks. Catoctin Mountain Park (CATO) in Maryland supports a prized trout fishery and a healthy community of native fishes, with one exception: native Blue Ridge Sculpin (Cottus caeruleomentum) appear to have been extirpated from Big Hunting Creek above Cunningham Falls. Infection by a fungal-like protist Dermocystidium is...
Learn More
link
Project eTrout Graphic

Project eTrout—Linking Research and Education with Virtual Reality

In the Chesapeake Bay headwaters, native brook trout are economically and culturally important and require high-quality, cold-water habitats. Project eTrout, led by the U.S. Geological Survey (USGS), explores the use of crowdsourcing and virtual reality (VR) to estimate the abundance of brook trout in headwater streams of the Chesapeake Bay watershed. Project eTrout engages students, anglers, and...
By
Chesapeake Bay Activities
link

Project eTrout—Linking Research and Education with Virtual Reality

In the Chesapeake Bay headwaters, native brook trout are economically and culturally important and require high-quality, cold-water habitats. Project eTrout, led by the U.S. Geological Survey (USGS), explores the use of crowdsourcing and virtual reality (VR) to estimate the abundance of brook trout in headwater streams of the Chesapeake Bay watershed. Project eTrout engages students, anglers, and...
Learn More
link
Hydrological framework

A hydrological framework to improve precision of Vital Signs metrics in the Appalachian highlands

Stream flow is a fundamental driver of ecological structure and function, but its influence on bioassessment measures is poorly understood. Although extreme flow conditions (e.g., floods and droughts) have long been known to play a central role in structuring stream communities, a mechanistic understanding of the linkages between flow variables, landscape and local physical characteristics, and...
By
Ecosystems Mission Area, Species Management Research Program, Eastern Ecological Science Center
link

A hydrological framework to improve precision of Vital Signs metrics in the Appalachian highlands

Stream flow is a fundamental driver of ecological structure and function, but its influence on bioassessment measures is poorly understood. Although extreme flow conditions (e.g., floods and droughts) have long been known to play a central role in structuring stream communities, a mechanistic understanding of the linkages between flow variables, landscape and local physical characteristics, and...
Learn More
link
USGS

Project eTrout

Welcome to Project eTrout [instructional video]! Click here to begin. Click here for a summary of results. Virtual reality (VR) provides exciting opportunities for environmental education and research. We invite your participation in a new program to engage students, anglers, and citizen scientists in fish ecology and climate change research using new VR methods. Participants will learn about fish...
By
Eastern Ecological Science Center
link

Project eTrout

Welcome to Project eTrout [instructional video]! Click here to begin. Click here for a summary of results. Virtual reality (VR) provides exciting opportunities for environmental education and research. We invite your participation in a new program to engage students, anglers, and citizen scientists in fish ecology and climate change research using new VR methods. Participants will learn about fish...
Learn More
Filter Total Items: 16

Brook trout abundance within pools of Staunton River and Paine Run in Shenandoah National Park from 2012-2021

This Data Release provides brook trout abundance records for pool habitats within 2 streams in Shenandoah National Park (Staunton River and Paine Run). The data were collected with 3-pass backpack electrofishing conducted during baseflow conditions between 2012-2021. This dataset enables spatial analysis of brook trout population responses to drought conditions.
By
Eastern Ecological Science Center

Brook trout abundance in streams across southern Appalachia from 1958-2021

This Data Release compiles records of brook trout abundance from 745 unique sites across the southern Appalachian mountains from 1958-2021. Records were compiled from 10 institutions, primarily state natural resource agencies. Data were collected from wadeable stream environments with standard backpack electrofishing methods, and observed abundances of adult and juvenile brook trout are reported f
By
Eastern Ecological Science Center

Stream temperature data for sites in the Potomac River headwaters during 2022

This Data Release contains stream temperature data for 12 sites within the headwaters of the Potomac River basin. Data were collected between June 1-August 31, 2022 (92 days) at 30-minute increments. We collected data using Onset ProV2 gages in perforated PVC cases mounted to stream substrates with rebar. This work was funded by the USGS Priority Ecosystem Science program for the Chesapeake Bay.
By
Eastern Ecological Science Center

Fish species abundance data for selected streams of the Potomac River basin

This Data Release contains data on fish species abundance for selected streams of the Potomac River basin in eastern North America. This dataset supports analysis of karst streams in the Chesapeake Bay headwaters region and was funded by USGS Chesapeake Bay studies.
By
Eastern Ecological Science Center

Stream temperature observations during summer 2021 for sites in the Antietam Creek watershed, Maryland

This Data Release contains stream temperature observations for 28 sites in the Antietam Creek Watershed (Maryland) during summer 2021. Data were collected using Onset ProV2 temperature gages within perforated PVC cases attached to stream substrates with rebar. Temperature gages were deployed and retrieved by volunteers with the Antietam-Conococheague Watershed Alliance. Temperature records are pro
By
Eastern Ecological Science Center

Brook trout imagery data for individual recognition with deep learning

This Data Release provides imagery data for the development of deep-learning models to recognize individual brook trout (n=435). Images were collected at the Paint Bank State Fish Hatchery (Paint Bank, VA) on August 9, 2021 using a GoPro Hero 9 camera mounted approximately 50 cm above a fish board. The Paint Bank State Fish Hatchery is operated by the Virginia Department of Wildlife Resources.
By
Eastern Ecological Science Center

USGS EcoDrought Stream Discharge, Gage Height, and Water Temperature in Shenandoah National Park, Virginia

The U.S. Geological Survey (USGS) Water Mission Area (WMA) - Ecosystems Mission Area (EMA) EcoDrought project is comprised of interdisciplinary teams in five pilot regions across the country. The over-arching project goal is to measure streamflow in headwater streams and to relate flow variation to stream fish population dynamics. For the catchments located in Shenandoah National Park, Virginia,
By
Eastern Ecological Science Center, New England Water Science Center

USGS EcoDrought Stream Discharge, Gage Height, and Water Temperature Data in Massachusetts

The USGS Water Mission Area (WMA) - Ecosystems Mission Area (EMA) EcoDrought project is comprised of interdisciplinary teams in five pilot regions across the country. The over-arching project goal is to measure streamflow in headwater streams and to relate flow variation to stream fish population dynamics. In the northeast, the New England Water Science Center (NewEngWSC) partnered with the fish
By
Eastern Ecological Science Center, New England Water Science Center

Stream temperature observations during summer 2021 for sites in the Sleepy Creek watershed, West Virginia

This Data Release contains stream temperature observations for 10 sites in the Sleepy Creek Watershed (West Virginia) during summer 2021. Data were collected using Onset ProV2 temperature gages within perforated PVC cases attached to stream substrates with rebar. Temperature gages were deployed and retrieved by volunteers with the Sleepy Creek Watershed Association. Temperature records are provide
By
Eastern Ecological Science Center

Annotated fish imagery data for individual and species recognition with deep learning

We provide annotated fish imagery data for use in deep learning models (e.g., convolutional neural networks) for individual and species recognition. For individual recognition models, the dataset consists of annotated .json files of individual brook trout imagery collected at the Eastern Ecological Science Center's Experimental Stream Laboratory. For species recognition models, the dataset consist
By
Eastern Ecological Science Center

Spatial patterns of dewatering within watersheds of Shenandoah National Park, Virginia 2016 - 2021 (ver. 2.0, December 2021)

These data describe longitudinal (upstream to downstream) patterns of dewatering during summer baseflow (July-September) conditions in nine watersheds in Shenandoah National park. In July-August of 2016 all nine watersheds (Jeremy's Run, Hazel River, Piney River, Hughes River, Staunton River, Whiteoak Canyon Run, Paine Run, Meadow Run, and Big Run) were evaluated for dewatering. In September of 20
By
Eastern Ecological Science Center

Stream temperature and sculpin growth data collected from Catoctin Mountain Park in 2019

This Data Release includes records of stream temperature during summer months of 2019 (10 sites) and records of Blue Ridge sculpin (Cottus caeruleomentum) weight for fish held in experimental enclosures for 45 days during the temperature sampling period (5 sites).
By
Eastern Ecological Science Center
A biologist installs a passive integrated transponder (PIT) tag into a brook trout
link
Biologist prepare brook trout for a study of environmental DNA (eDNA)
link
Biologists photograph brook trout as part of a study on environmental DNA (eDNA)
link
A biologist measures the length of a brook trout on a fish board.
link
Work station for fish species identification showing a dissecting microscope
link
A Blue Ridge sculpin is evaluated for Dermocystidium cysts on its gills
link
Restoring a native fish to Catoctin Mountain Park
link
A USGS technician inserts a small electrical device (about the size of a grain of rice) into an anesthetized fish
link
Photo of a brook trout observed in Owens Creek, Maryland
link
Fish held in a cooler are receiving water from larger tanks to acclimate them before introduction into the larger tanks.
link
USGS researchers are inspecting small fish specimens to identify their species.
link
This photo shows USGS researchers Kyle Fronte and Karli Rogers measuring stream flow.
link
Conductivity, water temperature, and water level gages in Bullskin Run, West Virginia.
link
Eastern Ecological Science Center - WV campus
link
This laboratory consists of 4 recirculating streams with pool and riffle habitat features
link
Filter Total Items: 42

Karst terrain promotes thermal resiliency in headwater streams

The response of stream ecosystems to climate change will depend in part on groundwater processes that reduce the sensitivity of streams to atmospheric conditions.  We investigated the thermal sensitivity of streams across a gradient of groundwater inputs defined by karst terrain (carbonate parent materials) in the headwaters of the Potomac River basin in eastern North America.  We collected stream
Authors
Karmann G. Kessler, Karli M Rogers, Charles Marshak, Nathaniel P. Hitt
By
Ecosystems Mission Area, Eastern Ecological Science Center

Stabilising effects of karstic groundwater on stream fish communities

Although groundwater exchange processes are known to modulate atmospheric influences on stream temperature and flow, the implications for ecological stability are poorly understood. Here, we evaluated temporal change in stream fish communities across a gradient of groundwater influence defined by karst terrain (carbonate parent materials) within the Potomac River basin of eastern North America. We
Authors
Nathaniel P. Hitt, Karli M Rogers, Karmann G. Kessler, Martin Briggs, Jennifer Burlingame Hoyle Fair
By
Ecosystems Mission Area, Water Resources Mission Area, Eastern Ecological Science Center, New England Water Science Center

Bedrock depth influences spatial patterns of summer baseflow, temperature and flow disconnection for mountainous headwater streams

In mountain headwater streams, the quality and resilience of summer cold-water habitat is generally regulated by stream discharge, longitudinal stream channel connectivity and groundwater exchange. These critical hydrologic processes are thought to be influenced by the stream corridor bedrock contact depth (sediment thickness), a parameter often inferred from sparse hillslope borehole information,
Authors
Martin Briggs, Phillip J. Goodling, Zachary Johnson, Karli M. Rogers, Nathaniel P. Hitt, Jennifer Burlingame Hoyle Fair, Craig D. Snyder
By
Ecosystems Mission Area, Water Resources Mission Area, Chesapeake Bay Activities, Eastern Ecological Science Center, New England Water Science Center, Washington Water Science Center

Spout Run temperature study revisited- Part II: New insights for trout habitat from TU & USGS collaboration 2022

The Winchester TU Chapter partnered with US Geological Survey scientists to forecast habitat conditions for brook trout in Virginia. The results can be viewed here: https://chesapeake.usgs.gov/fishforecast/ TU members deployed stream temperature gages within several streams across the region: Dry River, Passage Creek, Spout Run, Beaver Creek, Mossy Creek. The USGS then used the temperature data to
Authors
Nathaniel P. Hitt
By
Eastern Ecological Science Center

Stream size, temperature, and density explain body sizes of freshwater salmonids across a range of climate conditions

Climate change and anthropogenic activities are altering the body sizes of fishes, yet our understanding of factors influencing body size for many taxa remains incomplete. We evaluated the relationships between climate, environmental, and landscape attributes and the body size of different taxa of freshwater trout (Salmonidae) in the USA. Hierarchical spatial modeling across a gradient of habitats
Authors
Robert K. Al-Chokhachy, Benjamin Letcher, Clint C. Muhlfeld, Jason Dunham, Timothy Joseph Cline, Nathaniel P. Hitt, James Roberts, David Schmetterling
By
Ecosystems Mission Area, Fort Collins Science Center, Eastern Ecological Science Center, Northern Rocky Mountain Science Center

Life history strategies of stream fishes linked to predictors of hydrologic stability

Life history theory provides a framework to understand environmental change based on species strategies for survival and reproduction under stable, cyclical, or stochastic environmental conditions. We evaluated environmental predictors of fish life history strategies in 20 streams intersecting a national park within the Potomac River basin in eastern North America. We sampled stream sites during 2
Authors
Nathaniel P. Hitt, Andrew P Landsman, Richard L. Raesly
By
Ecosystems Mission Area, Chesapeake Bay Activities, Eastern Ecological Science Center

Comparative morphology of freshwater sculpin inhabiting different environmental conditions in the Chesapeake Bay headwaters

We compared body morphology of two freshwater sculpin taxa that inhabit distinct environmental conditions in the Chesapeake Bay watershed of eastern North America: Potomac sculpin (C. girardi, Robins; PS) and checkered sculpin (C. sp. cf. girardi; CS). Both taxa are endemic to the study area, but PS are more broadly distributed than CS which are limited to karst groundwater-dominated streams in th
Authors
Nathaniel P. Hitt, Karmann G. Kessler, Hannah Eisemann Macmillan, Karli M Rogers, Richard L. Raesly
By
Ecosystems Mission Area, Eastern Ecological Science Center, Chesapeake Bay Activities

Response of aquatic life to coal mining in Appalachia

No abstract available. 
Authors
George T. Merovich, Nathaniel P. Hitt, Eric R. Merriam, Jess Jones
By
Ecosystems Mission Area, Eastern Ecological Science Center

Assessing native fish restoration potential in Catoctin Mountain Park

Biological conservation is a fundamental purpose of the National Park system, and Catoctin Mountain Park (CATO) supports high-quality habitat for native fishes in the headwaters of the Chesapeake Bay watershed in eastern North America. However, native Blue Ridge sculpin (Cottus caeruleomentum) have been extirpated in Big Hunting Creek above Cunningham Falls in CATO. Prior research indicates that i
Authors
Nathaniel P. Hitt, Karmann G. Kessler, Zachary A. Kelly, Karli M. Rogers, Hannah E. Macmillan, Heather L. Walsh
By
Ecosystems Mission Area, Eastern Ecological Science Center, Chesapeake Bay Activities

Heed the data gap: Guidelines for using incomplete datasets in annual stream temperature analyses

Stream temperature data are useful for deciphering watershed processes important for aquatic ecosystems. Accurately extracting signal trends from stream temperature is essential for predicting responses of environmental and ecological indicators to change. Missing data periods are common for various reasons, and pose a challenge for scientists using temperature signal analysis to support stream re
Authors
Zachary C. Johnson, Brittany G. Johnson, Martin A. Briggs, Craig D. Snyder, Nathaniel P. Hitt, Warren Devine
By
Ecosystems Mission Area, Eastern Ecological Science Center

Modeling occupancy of rare stream fish species in the upper Cumberland and Kentucky River Basins

Biological conservation often requires an understanding of how environmental conditions affect species occurrence and detection probabilities. We used a hierarchical framework to evaluate these effects for several Appalachian stream fish species of conservation concern: Chrosomus cumberlandensis (BSD; blackside dace), Etheostoma sagitta (CAD; Cumberland arrow darter), and Etheostoma spilotum (KAD;
Authors
Nathaniel P. Hitt, Karli M. Rogers, Karmann Kessler, Hannah E. Macmillan
By
Ecosystems Mission Area, Eastern Ecological Science Center

Comparison of underwater video with electrofishing and dive‐counts for stream fish abundance estimation

Advances in video technology enable new strategies for stream fish research. We compared juvenile (age‐0) and adult (age 1+) Brook Trout Salvelinus fontinalis abundance estimates from underwater video with backpack electrofishing and dive‐count methods across a series of stream pools in Shenandoah National Park, Virginia (n = 41). Video methods estimated greater mean abundance of adult trout than
Authors
Nathaniel P. Hitt, Karli M Rogers, Craig D. Snyder, C. Andrew Dolloff
By
Ecosystems Mission Area, Eastern Ecological Science Center, Chesapeake Bay Activities

Non-USGS Publications**

Hitt, N.P. and M. Hendryx. 2010. Ecological integrity of streams linked to human cancer mortality rates. EcoHealth 7:91-104.
Hitt, N.P. and P.L. Angermeier. 2008. River-stream connectivity affects fish bioassessment performance. Environmental Management 42:132-150.
Hitt, N.P. and P.L. Angermeier. 2008. Evidence for fish dispersal from spatial analysis of stream network topology. Journal of the North American Benthological Society 27:304-320.
Hitt, N.P. and B.R. Murphy. 2007. An inquiry-based case study for conservation biology. Journal of Virginia Science Education 2:43-50.
Hitt, N.P. and P.L. Angermeier. 2006. Effects of adjacent streams on local fish assemblage structure in western Virginia: implications for biomonitoring. American Fisheries Society Symposium 48:75-86.
Vignieri, S.N., E.M. Hallerman, B.J. Bergstrom, D.J. Hafner, A.P. Martin, P. Devers, P. Grobler and N.P. Hitt. 2006. Mistaken view of taxonomy undermines conservation of an evolutionarily distinct mouse: a response to Ramey et al. Journal of Animal Conservation 9:237-243.
Allendorf, F.W., R. Leary, N.P. Hitt, K. Knudsen, M. Boyer and P. Spruell. 2005. Cutthroat trout hybridization and the U.S. Endangered Species Act: one species, two policies. Conservation Biology 19:1326-1328.
Hitt, N.P. and C.A. Frissell. 2004. A case study of surrogate species in aquatic conservation planning. Aquatic Conservation: Marine and Freshwater Ecosystems 14:625-633.
Allendorf, F.W., R. Leary, N.P. Hitt, K. Knudsen, L. Lundquist, and P. Spruell. 2004. Intercrosses and the U.S. Endangered Species Act: should hybridized populations be included as westslope cutthroat trout? Conservation Biology 18: 1203-1213.
Hitt, N.P., C.A. Frissell, C.C. Muhlfeld and F.W. Allendorf. 2003. Spread of hybridization between native westslope cutthroat trout, Oncorhynchus clarki lewisi, and non-native rainbow trout, O. mykiss. Canadian Journal of Fisheries and Aquatic Sciences 60:1440-1451.
Hitt, N.P. 2003. Immediate effects of wildfire on stream temperature. Journal of Freshwater Ecology 18:171-173.

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

link

USGS Study Reveals Interactive Effects of Climate Change, Invasive Species on Native Fish

A new USGS study shows non-native Brown Trout can place a burden on native Brook Trout under the increased water temperatures climate change can cause...

Read Article
link

Fish Populations Down Due to Mountaintop Mining

Appalachian streams impacted by mountaintop mining have less than half as many fish species and about a third as many fish as non-impacted streams...
Read Article

Science and Products

  • Science
    Filter Total Items: 15
    link
    A green sunfish

    Study reveals importance of groundwater for stability of freshwater fish populations and resilience to climate change

    Issue: Climate change is warming streams and rivers of the Chesapeake Bay watershed, and this is a critical concern for fisheries management and conservation. To address this issue, the Chesapeake Bay Program (CBP) recently identified four actions: • address the threats of climate change in all aspects of the partnership’s work; • prioritize communities, working lands, and most vulnerable habitats...
    By
    Chesapeake Bay Activities, Eastern Ecological Science Center
    link

    Study reveals importance of groundwater for stability of freshwater fish populations and resilience to climate change

    Issue: Climate change is warming streams and rivers of the Chesapeake Bay watershed, and this is a critical concern for fisheries management and conservation. To address this issue, the Chesapeake Bay Program (CBP) recently identified four actions: • address the threats of climate change in all aspects of the partnership’s work; • prioritize communities, working lands, and most vulnerable habitats...
    Learn More
    link
    Brook trout image

    Brook trout vulnerability to drought: eastern component of USGS national integrated ecohydrological research

    There is a growing and urgent need to develop and implement innovative strategies to research, monitor, and manage freshwater resources as societal demands escalate simultaneously with climate-driven changes in water availability.
    By
    Ecosystems Mission Area, Species Management Research Program, Eastern Ecological Science Center
    link

    Brook trout vulnerability to drought: eastern component of USGS national integrated ecohydrological research

    There is a growing and urgent need to develop and implement innovative strategies to research, monitor, and manage freshwater resources as societal demands escalate simultaneously with climate-driven changes in water availability.
    Learn More
    link
    Image Collage of Landsat, pollinator, and volcanologist

    Study of stream fishes provides new framework to monitor climate change in the Chesapeake Bay headwaters

    Issue: The Chesapeake Bay Program (CBP) have identified four goals for actions toward change climate: • address the threats of climate change in all aspects of the partnership’s work; • prioritize communities, working lands, and most vulnerable habitats; • apply the best scientific, modeling, monitoring and planning capabilities; and • connect restoration outcomes with emerging opportunities. A...
    By
    Chesapeake Bay Activities
    link

    Study of stream fishes provides new framework to monitor climate change in the Chesapeake Bay headwaters

    Issue: The Chesapeake Bay Program (CBP) have identified four goals for actions toward change climate: • address the threats of climate change in all aspects of the partnership’s work; • prioritize communities, working lands, and most vulnerable habitats; • apply the best scientific, modeling, monitoring and planning capabilities; and • connect restoration outcomes with emerging opportunities. A...
    Learn More
    link
    brook trout

    Enabling AI for citizen science in fish biology

    Artificial Intelligence (AI) is revolutionizing ecology and conservation by enabling species recognition from photos and videos. Our project evaluates the capacity to expand AI for individual fish recognition for population assessment. The success of this effort would facilitate fisheries analysis at an unprecedented scale by engaging anglers and citizen scientists in imagery collection. This...
    By
    Core Science Systems Mission Area, Ecosystems Mission Area, Species Management Research Program, Eastern Ecological Science Center
    link

    Enabling AI for citizen science in fish biology

    Artificial Intelligence (AI) is revolutionizing ecology and conservation by enabling species recognition from photos and videos. Our project evaluates the capacity to expand AI for individual fish recognition for population assessment. The success of this effort would facilitate fisheries analysis at an unprecedented scale by engaging anglers and citizen scientists in imagery collection. This...
    Learn More
    link
    Brook trout

    Effects of introduced species on native brook trout: a guide to the scientific literature

    Issue: Native brook trout (Salvelinus fontinalis) are of great ecological, cultural, and economic importance in eastern North America, and their restoration is a focus of the Chesapeake Bay Program. Introduced, non-native species can jeopardize native brook trout, and more information on these effects are needed.
    By
    Core Science Systems Mission Area, Chesapeake Bay Activities
    link

    Effects of introduced species on native brook trout: a guide to the scientific literature

    Issue: Native brook trout (Salvelinus fontinalis) are of great ecological, cultural, and economic importance in eastern North America, and their restoration is a focus of the Chesapeake Bay Program. Introduced, non-native species can jeopardize native brook trout, and more information on these effects are needed.
    Learn More
    link
    USGS science for a changing world logo

    Enabling AI for citizen science in fish ecology

    Artificial Intelligence (AI) is revolutionizing ecology and conservation by enabling species recognition from photos and videos. Our project evaluates the capacity to expand AI for individual fish recognition for population assessment. The success of this effort would facilitate fisheries analysis at an unprecedented scale by engaging anglers and citizen scientists in imagery collection.This proje
    By
    Community for Data Integration (CDI)
    link

    Enabling AI for citizen science in fish ecology

    Artificial Intelligence (AI) is revolutionizing ecology and conservation by enabling species recognition from photos and videos. Our project evaluates the capacity to expand AI for individual fish recognition for population assessment. The success of this effort would facilitate fisheries analysis at an unprecedented scale by engaging anglers and citizen scientists in imagery collection.This proje
    Learn More
    link
    Dr. Kent Crawford lifts a carp caught during a 2015 electro-fishing survey for Smallmouth Bass on the Conodoguinet Creek.

    Changing Freshwater Flows Affect Fish Populations in the Potomac River

    Issue: Millions of people rely on the Potomac River for drinking water and recreational opportunities. The Potomac is Maryland’s most popular freshwater fishing destination, and the second largest river that enters the Chesapeake Bay. Restoring fisheries is also an important goal for the Chesapeake Bay Partnership restoration efforts.
    By
    Core Science Systems Mission Area, Chesapeake Bay Activities
    link

    Changing Freshwater Flows Affect Fish Populations in the Potomac River

    Issue: Millions of people rely on the Potomac River for drinking water and recreational opportunities. The Potomac is Maryland’s most popular freshwater fishing destination, and the second largest river that enters the Chesapeake Bay. Restoring fisheries is also an important goal for the Chesapeake Bay Partnership restoration efforts.
    Learn More
    link
    A bright red underbelly of a trout is shown as the fish is swimming in a shallow rocky stream.

    Brook Trout Population Responses to Climate Variation Across the Southeast USA

    Brook trout are the only native fish from the salmon family in the southeastern United States. Despite their recreational and cultural significance, human activities, such as habitat degradation and introduction of non-native species, have led to serious declines of brook trout populations in the region. Stream temperature and flow alterations from climate change are projected to impact this cold-
    By
    Climate Adaptation Science Centers
    link

    Brook Trout Population Responses to Climate Variation Across the Southeast USA

    Brook trout are the only native fish from the salmon family in the southeastern United States. Despite their recreational and cultural significance, human activities, such as habitat degradation and introduction of non-native species, have led to serious declines of brook trout populations in the region. Stream temperature and flow alterations from climate change are projected to impact this cold-
    Learn More
    link
    Blue Ridge Sculpin

    Restoring a native fish to Catoctin Mountain Park

    Native species conservation is a fundamental purpose of National Parks. Catoctin Mountain Park (CATO) in Maryland supports a prized trout fishery and a healthy community of native fishes, with one exception: native Blue Ridge Sculpin (Cottus caeruleomentum) appear to have been extirpated from Big Hunting Creek above Cunningham Falls. Infection by a fungal-like protist Dermocystidium is...
    By
    Ecosystems Mission Area, Species Management Research Program, Eastern Ecological Science Center
    link

    Restoring a native fish to Catoctin Mountain Park

    Native species conservation is a fundamental purpose of National Parks. Catoctin Mountain Park (CATO) in Maryland supports a prized trout fishery and a healthy community of native fishes, with one exception: native Blue Ridge Sculpin (Cottus caeruleomentum) appear to have been extirpated from Big Hunting Creek above Cunningham Falls. Infection by a fungal-like protist Dermocystidium is...
    Learn More
    link
    Project eTrout Graphic

    Project eTrout—Linking Research and Education with Virtual Reality

    In the Chesapeake Bay headwaters, native brook trout are economically and culturally important and require high-quality, cold-water habitats. Project eTrout, led by the U.S. Geological Survey (USGS), explores the use of crowdsourcing and virtual reality (VR) to estimate the abundance of brook trout in headwater streams of the Chesapeake Bay watershed. Project eTrout engages students, anglers, and...
    By
    Chesapeake Bay Activities
    link

    Project eTrout—Linking Research and Education with Virtual Reality

    In the Chesapeake Bay headwaters, native brook trout are economically and culturally important and require high-quality, cold-water habitats. Project eTrout, led by the U.S. Geological Survey (USGS), explores the use of crowdsourcing and virtual reality (VR) to estimate the abundance of brook trout in headwater streams of the Chesapeake Bay watershed. Project eTrout engages students, anglers, and...
    Learn More
    link
    Hydrological framework

    A hydrological framework to improve precision of Vital Signs metrics in the Appalachian highlands

    Stream flow is a fundamental driver of ecological structure and function, but its influence on bioassessment measures is poorly understood. Although extreme flow conditions (e.g., floods and droughts) have long been known to play a central role in structuring stream communities, a mechanistic understanding of the linkages between flow variables, landscape and local physical characteristics, and...
    By
    Ecosystems Mission Area, Species Management Research Program, Eastern Ecological Science Center
    link

    A hydrological framework to improve precision of Vital Signs metrics in the Appalachian highlands

    Stream flow is a fundamental driver of ecological structure and function, but its influence on bioassessment measures is poorly understood. Although extreme flow conditions (e.g., floods and droughts) have long been known to play a central role in structuring stream communities, a mechanistic understanding of the linkages between flow variables, landscape and local physical characteristics, and...
    Learn More
    link
    USGS

    Project eTrout

    Welcome to Project eTrout [instructional video]! Click here to begin. Click here for a summary of results. Virtual reality (VR) provides exciting opportunities for environmental education and research. We invite your participation in a new program to engage students, anglers, and citizen scientists in fish ecology and climate change research using new VR methods. Participants will learn about fish...
    By
    Eastern Ecological Science Center
    link

    Project eTrout

    Welcome to Project eTrout [instructional video]! Click here to begin. Click here for a summary of results. Virtual reality (VR) provides exciting opportunities for environmental education and research. We invite your participation in a new program to engage students, anglers, and citizen scientists in fish ecology and climate change research using new VR methods. Participants will learn about fish...
    Learn More
  • Data
    Filter Total Items: 16

    Brook trout abundance within pools of Staunton River and Paine Run in Shenandoah National Park from 2012-2021

    This Data Release provides brook trout abundance records for pool habitats within 2 streams in Shenandoah National Park (Staunton River and Paine Run). The data were collected with 3-pass backpack electrofishing conducted during baseflow conditions between 2012-2021. This dataset enables spatial analysis of brook trout population responses to drought conditions.
    By
    Eastern Ecological Science Center

    Brook trout abundance in streams across southern Appalachia from 1958-2021

    This Data Release compiles records of brook trout abundance from 745 unique sites across the southern Appalachian mountains from 1958-2021. Records were compiled from 10 institutions, primarily state natural resource agencies. Data were collected from wadeable stream environments with standard backpack electrofishing methods, and observed abundances of adult and juvenile brook trout are reported f
    By
    Eastern Ecological Science Center

    Stream temperature data for sites in the Potomac River headwaters during 2022

    This Data Release contains stream temperature data for 12 sites within the headwaters of the Potomac River basin. Data were collected between June 1-August 31, 2022 (92 days) at 30-minute increments. We collected data using Onset ProV2 gages in perforated PVC cases mounted to stream substrates with rebar. This work was funded by the USGS Priority Ecosystem Science program for the Chesapeake Bay.
    By
    Eastern Ecological Science Center

    Fish species abundance data for selected streams of the Potomac River basin

    This Data Release contains data on fish species abundance for selected streams of the Potomac River basin in eastern North America. This dataset supports analysis of karst streams in the Chesapeake Bay headwaters region and was funded by USGS Chesapeake Bay studies.
    By
    Eastern Ecological Science Center

    Stream temperature observations during summer 2021 for sites in the Antietam Creek watershed, Maryland

    This Data Release contains stream temperature observations for 28 sites in the Antietam Creek Watershed (Maryland) during summer 2021. Data were collected using Onset ProV2 temperature gages within perforated PVC cases attached to stream substrates with rebar. Temperature gages were deployed and retrieved by volunteers with the Antietam-Conococheague Watershed Alliance. Temperature records are pro
    By
    Eastern Ecological Science Center

    Brook trout imagery data for individual recognition with deep learning

    This Data Release provides imagery data for the development of deep-learning models to recognize individual brook trout (n=435). Images were collected at the Paint Bank State Fish Hatchery (Paint Bank, VA) on August 9, 2021 using a GoPro Hero 9 camera mounted approximately 50 cm above a fish board. The Paint Bank State Fish Hatchery is operated by the Virginia Department of Wildlife Resources.
    By
    Eastern Ecological Science Center

    USGS EcoDrought Stream Discharge, Gage Height, and Water Temperature in Shenandoah National Park, Virginia

    The U.S. Geological Survey (USGS) Water Mission Area (WMA) - Ecosystems Mission Area (EMA) EcoDrought project is comprised of interdisciplinary teams in five pilot regions across the country. The over-arching project goal is to measure streamflow in headwater streams and to relate flow variation to stream fish population dynamics. For the catchments located in Shenandoah National Park, Virginia,
    By
    Eastern Ecological Science Center, New England Water Science Center

    USGS EcoDrought Stream Discharge, Gage Height, and Water Temperature Data in Massachusetts

    The USGS Water Mission Area (WMA) - Ecosystems Mission Area (EMA) EcoDrought project is comprised of interdisciplinary teams in five pilot regions across the country. The over-arching project goal is to measure streamflow in headwater streams and to relate flow variation to stream fish population dynamics. In the northeast, the New England Water Science Center (NewEngWSC) partnered with the fish
    By
    Eastern Ecological Science Center, New England Water Science Center

    Stream temperature observations during summer 2021 for sites in the Sleepy Creek watershed, West Virginia

    This Data Release contains stream temperature observations for 10 sites in the Sleepy Creek Watershed (West Virginia) during summer 2021. Data were collected using Onset ProV2 temperature gages within perforated PVC cases attached to stream substrates with rebar. Temperature gages were deployed and retrieved by volunteers with the Sleepy Creek Watershed Association. Temperature records are provide
    By
    Eastern Ecological Science Center

    Annotated fish imagery data for individual and species recognition with deep learning

    We provide annotated fish imagery data for use in deep learning models (e.g., convolutional neural networks) for individual and species recognition. For individual recognition models, the dataset consists of annotated .json files of individual brook trout imagery collected at the Eastern Ecological Science Center's Experimental Stream Laboratory. For species recognition models, the dataset consist
    By
    Eastern Ecological Science Center

    Spatial patterns of dewatering within watersheds of Shenandoah National Park, Virginia 2016 - 2021 (ver. 2.0, December 2021)

    These data describe longitudinal (upstream to downstream) patterns of dewatering during summer baseflow (July-September) conditions in nine watersheds in Shenandoah National park. In July-August of 2016 all nine watersheds (Jeremy's Run, Hazel River, Piney River, Hughes River, Staunton River, Whiteoak Canyon Run, Paine Run, Meadow Run, and Big Run) were evaluated for dewatering. In September of 20
    By
    Eastern Ecological Science Center

    Stream temperature and sculpin growth data collected from Catoctin Mountain Park in 2019

    This Data Release includes records of stream temperature during summer months of 2019 (10 sites) and records of Blue Ridge sculpin (Cottus caeruleomentum) weight for fish held in experimental enclosures for 45 days during the temperature sampling period (5 sites).
    By
    Eastern Ecological Science Center
  • Multimedia
    A biologist installs a passive integrated transponder (PIT) tag into a brook trout
    link
    Biologist prepare brook trout for a study of environmental DNA (eDNA)
    link
    Biologists photograph brook trout as part of a study on environmental DNA (eDNA)
    link
    A biologist measures the length of a brook trout on a fish board.
    link
    Work station for fish species identification showing a dissecting microscope
    link
    A Blue Ridge sculpin is evaluated for Dermocystidium cysts on its gills
    link
    Restoring a native fish to Catoctin Mountain Park
    link
    A USGS technician inserts a small electrical device (about the size of a grain of rice) into an anesthetized fish
    link
    Photo of a brook trout observed in Owens Creek, Maryland
    link
    Fish held in a cooler are receiving water from larger tanks to acclimate them before introduction into the larger tanks.
    link
    USGS researchers are inspecting small fish specimens to identify their species.
    link
    This photo shows USGS researchers Kyle Fronte and Karli Rogers measuring stream flow.
    link
    Conductivity, water temperature, and water level gages in Bullskin Run, West Virginia.
    link
    Eastern Ecological Science Center - WV campus
    link
    This laboratory consists of 4 recirculating streams with pool and riffle habitat features
    link
  • Publications
    Filter Total Items: 42

    Karst terrain promotes thermal resiliency in headwater streams

    The response of stream ecosystems to climate change will depend in part on groundwater processes that reduce the sensitivity of streams to atmospheric conditions.  We investigated the thermal sensitivity of streams across a gradient of groundwater inputs defined by karst terrain (carbonate parent materials) in the headwaters of the Potomac River basin in eastern North America.  We collected stream
    Authors
    Karmann G. Kessler, Karli M Rogers, Charles Marshak, Nathaniel P. Hitt
    By
    Ecosystems Mission Area, Eastern Ecological Science Center

    Stabilising effects of karstic groundwater on stream fish communities

    Although groundwater exchange processes are known to modulate atmospheric influences on stream temperature and flow, the implications for ecological stability are poorly understood. Here, we evaluated temporal change in stream fish communities across a gradient of groundwater influence defined by karst terrain (carbonate parent materials) within the Potomac River basin of eastern North America. We
    Authors
    Nathaniel P. Hitt, Karli M Rogers, Karmann G. Kessler, Martin Briggs, Jennifer Burlingame Hoyle Fair
    By
    Ecosystems Mission Area, Water Resources Mission Area, Eastern Ecological Science Center, New England Water Science Center

    Bedrock depth influences spatial patterns of summer baseflow, temperature and flow disconnection for mountainous headwater streams

    In mountain headwater streams, the quality and resilience of summer cold-water habitat is generally regulated by stream discharge, longitudinal stream channel connectivity and groundwater exchange. These critical hydrologic processes are thought to be influenced by the stream corridor bedrock contact depth (sediment thickness), a parameter often inferred from sparse hillslope borehole information,
    Authors
    Martin Briggs, Phillip J. Goodling, Zachary Johnson, Karli M. Rogers, Nathaniel P. Hitt, Jennifer Burlingame Hoyle Fair, Craig D. Snyder
    By
    Ecosystems Mission Area, Water Resources Mission Area, Chesapeake Bay Activities, Eastern Ecological Science Center, New England Water Science Center, Washington Water Science Center

    Spout Run temperature study revisited- Part II: New insights for trout habitat from TU & USGS collaboration 2022

    The Winchester TU Chapter partnered with US Geological Survey scientists to forecast habitat conditions for brook trout in Virginia. The results can be viewed here: https://chesapeake.usgs.gov/fishforecast/ TU members deployed stream temperature gages within several streams across the region: Dry River, Passage Creek, Spout Run, Beaver Creek, Mossy Creek. The USGS then used the temperature data to
    Authors
    Nathaniel P. Hitt
    By
    Eastern Ecological Science Center

    Stream size, temperature, and density explain body sizes of freshwater salmonids across a range of climate conditions

    Climate change and anthropogenic activities are altering the body sizes of fishes, yet our understanding of factors influencing body size for many taxa remains incomplete. We evaluated the relationships between climate, environmental, and landscape attributes and the body size of different taxa of freshwater trout (Salmonidae) in the USA. Hierarchical spatial modeling across a gradient of habitats
    Authors
    Robert K. Al-Chokhachy, Benjamin Letcher, Clint C. Muhlfeld, Jason Dunham, Timothy Joseph Cline, Nathaniel P. Hitt, James Roberts, David Schmetterling
    By
    Ecosystems Mission Area, Fort Collins Science Center, Eastern Ecological Science Center, Northern Rocky Mountain Science Center

    Life history strategies of stream fishes linked to predictors of hydrologic stability

    Life history theory provides a framework to understand environmental change based on species strategies for survival and reproduction under stable, cyclical, or stochastic environmental conditions. We evaluated environmental predictors of fish life history strategies in 20 streams intersecting a national park within the Potomac River basin in eastern North America. We sampled stream sites during 2
    Authors
    Nathaniel P. Hitt, Andrew P Landsman, Richard L. Raesly
    By
    Ecosystems Mission Area, Chesapeake Bay Activities, Eastern Ecological Science Center

    Comparative morphology of freshwater sculpin inhabiting different environmental conditions in the Chesapeake Bay headwaters

    We compared body morphology of two freshwater sculpin taxa that inhabit distinct environmental conditions in the Chesapeake Bay watershed of eastern North America: Potomac sculpin (C. girardi, Robins; PS) and checkered sculpin (C. sp. cf. girardi; CS). Both taxa are endemic to the study area, but PS are more broadly distributed than CS which are limited to karst groundwater-dominated streams in th
    Authors
    Nathaniel P. Hitt, Karmann G. Kessler, Hannah Eisemann Macmillan, Karli M Rogers, Richard L. Raesly
    By
    Ecosystems Mission Area, Eastern Ecological Science Center, Chesapeake Bay Activities

    Response of aquatic life to coal mining in Appalachia

    No abstract available. 
    Authors
    George T. Merovich, Nathaniel P. Hitt, Eric R. Merriam, Jess Jones
    By
    Ecosystems Mission Area, Eastern Ecological Science Center

    Assessing native fish restoration potential in Catoctin Mountain Park

    Biological conservation is a fundamental purpose of the National Park system, and Catoctin Mountain Park (CATO) supports high-quality habitat for native fishes in the headwaters of the Chesapeake Bay watershed in eastern North America. However, native Blue Ridge sculpin (Cottus caeruleomentum) have been extirpated in Big Hunting Creek above Cunningham Falls in CATO. Prior research indicates that i
    Authors
    Nathaniel P. Hitt, Karmann G. Kessler, Zachary A. Kelly, Karli M. Rogers, Hannah E. Macmillan, Heather L. Walsh
    By
    Ecosystems Mission Area, Eastern Ecological Science Center, Chesapeake Bay Activities

    Heed the data gap: Guidelines for using incomplete datasets in annual stream temperature analyses

    Stream temperature data are useful for deciphering watershed processes important for aquatic ecosystems. Accurately extracting signal trends from stream temperature is essential for predicting responses of environmental and ecological indicators to change. Missing data periods are common for various reasons, and pose a challenge for scientists using temperature signal analysis to support stream re
    Authors
    Zachary C. Johnson, Brittany G. Johnson, Martin A. Briggs, Craig D. Snyder, Nathaniel P. Hitt, Warren Devine
    By
    Ecosystems Mission Area, Eastern Ecological Science Center

    Modeling occupancy of rare stream fish species in the upper Cumberland and Kentucky River Basins

    Biological conservation often requires an understanding of how environmental conditions affect species occurrence and detection probabilities. We used a hierarchical framework to evaluate these effects for several Appalachian stream fish species of conservation concern: Chrosomus cumberlandensis (BSD; blackside dace), Etheostoma sagitta (CAD; Cumberland arrow darter), and Etheostoma spilotum (KAD;
    Authors
    Nathaniel P. Hitt, Karli M. Rogers, Karmann Kessler, Hannah E. Macmillan
    By
    Ecosystems Mission Area, Eastern Ecological Science Center

    Comparison of underwater video with electrofishing and dive‐counts for stream fish abundance estimation

    Advances in video technology enable new strategies for stream fish research. We compared juvenile (age‐0) and adult (age 1+) Brook Trout Salvelinus fontinalis abundance estimates from underwater video with backpack electrofishing and dive‐count methods across a series of stream pools in Shenandoah National Park, Virginia (n = 41). Video methods estimated greater mean abundance of adult trout than
    Authors
    Nathaniel P. Hitt, Karli M Rogers, Craig D. Snyder, C. Andrew Dolloff
    By
    Ecosystems Mission Area, Eastern Ecological Science Center, Chesapeake Bay Activities

    Non-USGS Publications**

    Hitt, N.P. and M. Hendryx. 2010. Ecological integrity of streams linked to human cancer mortality rates. EcoHealth 7:91-104.
    Hitt, N.P. and P.L. Angermeier. 2008. River-stream connectivity affects fish bioassessment performance. Environmental Management 42:132-150.
    Hitt, N.P. and P.L. Angermeier. 2008. Evidence for fish dispersal from spatial analysis of stream network topology. Journal of the North American Benthological Society 27:304-320.
    Hitt, N.P. and B.R. Murphy. 2007. An inquiry-based case study for conservation biology. Journal of Virginia Science Education 2:43-50.
    Hitt, N.P. and P.L. Angermeier. 2006. Effects of adjacent streams on local fish assemblage structure in western Virginia: implications for biomonitoring. American Fisheries Society Symposium 48:75-86.
    Vignieri, S.N., E.M. Hallerman, B.J. Bergstrom, D.J. Hafner, A.P. Martin, P. Devers, P. Grobler and N.P. Hitt. 2006. Mistaken view of taxonomy undermines conservation of an evolutionarily distinct mouse: a response to Ramey et al. Journal of Animal Conservation 9:237-243.
    Allendorf, F.W., R. Leary, N.P. Hitt, K. Knudsen, M. Boyer and P. Spruell. 2005. Cutthroat trout hybridization and the U.S. Endangered Species Act: one species, two policies. Conservation Biology 19:1326-1328.
    Hitt, N.P. and C.A. Frissell. 2004. A case study of surrogate species in aquatic conservation planning. Aquatic Conservation: Marine and Freshwater Ecosystems 14:625-633.
    Allendorf, F.W., R. Leary, N.P. Hitt, K. Knudsen, L. Lundquist, and P. Spruell. 2004. Intercrosses and the U.S. Endangered Species Act: should hybridized populations be included as westslope cutthroat trout? Conservation Biology 18: 1203-1213.
    Hitt, N.P., C.A. Frissell, C.C. Muhlfeld and F.W. Allendorf. 2003. Spread of hybridization between native westslope cutthroat trout, Oncorhynchus clarki lewisi, and non-native rainbow trout, O. mykiss. Canadian Journal of Fisheries and Aquatic Sciences 60:1440-1451.
    Hitt, N.P. 2003. Immediate effects of wildfire on stream temperature. Journal of Freshwater Ecology 18:171-173.

    **Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

  • News
    link

    USGS Study Reveals Interactive Effects of Climate Change, Invasive Species on Native Fish

    A new USGS study shows non-native Brown Trout can place a burden on native Brook Trout under the increased water temperatures climate change can cause...

    Read Article
    link

    Fish Populations Down Due to Mountaintop Mining

    Appalachian streams impacted by mountaintop mining have less than half as many fish species and about a third as many fish as non-impacted streams...
    Read Article