Nathaniel (Than) Hitt, PhD
Biography
Dr. Nathaniel (Than) P. Hitt is a Research Fish Biologist at the USGS Leetown 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 and community ecotoxicology 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
Education
- 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
Professional experience
- 2009-present: Research Fish Biologist, US Geological Survey, Leetown Science Center
- 2018-present: Adjunct Associate Professor, Natural Resource Ecology & Management, Oklahoma State University
- 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
- 2002-2007: Graduate Research Assistant, Virginia Tech, Department of Fisheries and Wildlife Sciences
- 1999-2002: Graduate Research Assistant, University of Montana, Division of Biological Sciences
Link to Google Scholar profile
Science and Products
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.
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...
Enabling AI for citizen science in fish ecology
Artificial Intelligence (AI) isrevolutionizing ecologyand 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...
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.
Assessing native fish restoration potential in 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 ...
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,...
Brook trout vulnerability to drought: eastern component of USGS national integrated ecohydrological research and monitoring plans
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. Over the past several years, many regions have experienced extreme droughts, fueled by prolonged periods of reduced precipitation and exceptionally warm temperatures...
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,...
Project eTrout
Welcome to Project eTrout [instructional video]!
Click here to begin.
Click here for a summary of results.
Virtual reality (VR)...
USGS Expands Studies of Brook Trout
The USGS has established an experimental stream lab in the Leetown Science Center.
Bringing People, Data, and Models Together – Addressing Impacts of Climate Change on Stream Temperature
This study set out to answer the question: “What data and modeling frameworks are needed to provide scientists reliable, climate-informed, water temperature estimates for freshwater ecosystems that can assist watershed management decision making?” To accomplish this, the study gathered existing stream temperature data, identified data gaps, deployed stream temperature monitoring devices, and...
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...
Johnson, Zachary C.; Johnson, Brittany G.; Briggs, Martin A.; Snyder, Craig D.; Hitt, Nathaniel P.; Devine, WarrenAssessing 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...
Hitt, Nathaniel P.; Kessler, Karmann G.; Kelly, Zachary A.; Rogers, Karli M.; Macmillan, Hannah E.; Walsh, Heather L.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;...
Hitt, Nathaniel P.; Rogers, Karli M.; Kessler, Karmann; Macmillan, Hannah E.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)....
Hitt, Nathaniel P.; Rogers, Karli M; Snyder, Craig D.; Dolloff, C. AndrewSpatial and temporal trends in Potomac River fish abundance linked to species traits
Analysis of species abundance trends can inform an understanding of the underlying mechanisms. We evaluated spatial and temporal trends in fish species abundance in the non-tidal Potomac River (USA) from a dataset comprising 2841 seine-hauls with > 250,000 individual fish records across 10 sites and 43 years (1975-2017). The dataset contained...
Hitt, Nathaniel P.; Rogers, Karli; Kelly, Zachary A.; Henesy, Josh; Mullican, John E.Distribution and status of trout and char in North America
No abstract available.
Budy, Phaedra; Rogers, Kevin B.; Kanno, Yoichiro; Penaluna, Brooke E; Hitt, Nathaniel; Thiede, Gary P.; Dunham, Jason; Mellison, Chad; Somer, William; DeRito, JamesIndividual behaviour and resource use of thermally stressed brook trout Salvelinus fontinalis portend the conservation potential of thermal refugia
Individual aggression and thermal refuge use were monitored in brook trout Salvelinus fontinalis in a controlled laboratory to determine how fish size and personality influence time spent in forage and thermal habitat patches during periods of thermal stress. On average, larger and more exploratory fish initiated more aggressive...
White, Shannon L.; Kline, B.C.; Hitt, Nathaniel; Wagner, TylerAn integrated framework for ecological drought across riverscapes of North America
Climate change is increasing the severity and extent of extreme droughts events, posing a critical threat to freshwater ecosystems, particularly with increasing human demands for diminishing water supplies. Despite the importance of drought as a significant driver of ecological and evolutionary dynamics, current understanding of drought...
Kovach, Ryan; Dunham, Jason B.; Al-Chokhachy, Robert; Snyder, Craig; Beever, Erik A.; Pederson, Gregory T.; Lynch, Abigail; Hitt, Nathaniel P.; Konrad, Christopher P.; Jaeger, Kristin; Rea, Alan H.; Sepulveda, Adam J.; Lambert, Patrick M.; Stoker, Jason M.; Giersch, J. Joseph; Muhlfeld, Clint C.State-space analysis of power to detect regional brook trout population trends over time
Threats to aquatic biodiversity are expressed at broad spatial scales, but identifying regional trends in abundance is challenging owing to variable sampling designs, and temporal and spatial variation in abundance. We compiled a regional dataset of brook trout Salvelinus fontinalis counts across their southern range representing 326 sites from...
Pregler, Kasey C.; Hanks, R. Daniel; Childress, Evan S.; Hitt, Nathaniel P.; Hocking, Daniel J.; Letcher, Benjamin H.; Kanno, YoichiroInferring watershed hydraulics and cold-water habitat persistence using multi-year air and stream temperature signals
Streams strongly influenced by groundwater discharge may serve as “climate refugia” for sensitive species in regions of increasingly marginal thermal conditions. The main goal of this study is to develop paired air and stream water annual temperature signal analysis techniques to elucidate the relative groundwater contribution to stream water and...
Briggs, Martin A.; Johnson, Zachary C.; Snyder, Craig D.; Hitt, Nathaniel P.; Kurylyk, Barret L.; Lautz, Laura K.; Irvine, Dylan J.; Hurley, Stephen T.; Lane, Jr., John W.Shallow bedrock limits groundwater seepage-based headwater climate refugia
Groundwater/surface-water exchanges in streams are inexorably linked to adjacent aquifer dynamics. As surface-water temperatures continue to increase with climate warming, refugia created by groundwater connectivity is expected to enable cold water fish species to survive. The shallow alluvial aquifers that source groundwater seepage to headwater...
Briggs, Martin A.; Lane, John W.; Snyder, Craig D.; White, Eric A.; Johnson, Zachary; Nelms, David L.; Hitt, Nathaniel P.Forecasting stream habitat and Brook Trout responses to climate change in Catoctin Mountain Park
Anticipating and mitigating the effects of climate change is a fundamental challenge for natural resource conservation. In this report, we respond to research needs identified by Catoctin Mountain Park (CATO) for native Brook Trout (Salvelinus fontinalis) conservation and management as part of the US Geological Survey (USGS) Natural...
Hitt, Nathaniel P.; Snyder, Craig D.; Snook, Erin; Johnson, Zachary; Morgan, MatthewPre-USGS Publications
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.
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, according to U.S. Geological Survey research published this week in the journal Freshwater Science.