Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Benjamin H Letcher
Ben Letcher is an Ecologist at the USGS Eastern Ecological Science Center in Turners Falls, Massachusetts.
Ben is a population ecologist focusing on stream habitats, science communication and the development of data systems. A collection of data systems and interactive data visualization tools can be found in our EcoSHEDS environment.
Professional Experience
1995-now USGS, Ecology section leader, Anadromous Fish Research Center, Turners, Falls, MA, and adjunct professor Department of Natural Resources
Conservation, University of Massachusetts - Amherst1994-1995 Oak Ridge Postdoctoral Fellow (with Dr. David Conover) State University of New York, Stony Brook, NY
1992-1994 Electric Power Research Institute Fellow, North Carolina State University, Raleigh, NC
1990-1992 Wisconsin Sea Grant Fellow, North Carolina State University, Raleigh, NC
1987-1990 URI-USEPA Cooperative Research Fellow, University of Rhode Island, Kingston, RI
1986-1987 Research Assistant, Center for Coastal Studies, Provincetown, MA.
1985-1986 Research Assistant, University of Massachusetts, Amherst, MA.
Education and Certifications
PhD, 1994, NC State, Zoology with statistics and modeling minor
M.S. 1990, URI School of Oceanography, biological option
B.S. 1985, Trinity College, Biology
Science and Products
Brook trout vulnerability to drought: eastern component of USGS national integrated ecohydrological research
Integrating Streamflow and Temperature to Identify Streams with Coldwater Refugia in the Northeast
Enabling AI for citizen science in fish biology
Enhancing Water Temperature Monitoring Efforts across Alaska through Collaborative Leveraging of a Statewide Database
North Atlantic-Appalachian AI/ML Capabilities
Enabling AI for citizen science in fish ecology
Understanding Brook Trout Persistence in Warming Streams
Scoping the Feasibility of Incorporating Climate Change into Risk Assessments of Aquatic Invasive Species in the Upper Midwest
Brook Trout Population Responses to Climate Variation Across the Southeast USA
A generic web application to visualize and understand movements of tagged animals
Climate change forecasts for eastern salmonids
The West Brook Story
Longer exposure to warm water increases subsequent thermal tolerance of brook trout in cold water: acclimation timing and physiology Longer exposure to warm water increases subsequent thermal tolerance of brook trout in cold water: acclimation timing and physiology
Passive integrated transponder tag data from Sawmill River, Catamaran Brook and Shorey Brook Passive integrated transponder tag data from Sawmill River, Catamaran Brook and Shorey Brook
Model Predictions, Observations, and Annotation Data for Deep Learning Models Developed to Estimate Relative Flow at 11 Massachusetts Streamflow Sites, 2017-2024 Model Predictions, Observations, and Annotation Data for Deep Learning Models Developed to Estimate Relative Flow at 11 Massachusetts Streamflow Sites, 2017-2024
Loss of acclimation response of brook trout acclimated to three thermal regimes for 2-years and then moved to a common colder temperature Loss of acclimation response of brook trout acclimated to three thermal regimes for 2-years and then moved to a common colder temperature
Passive integrated transponder tag data from the West Brook, MA, USA Passive integrated transponder tag data from the West Brook, MA, USA
Data for examining thermal equilibration rates of brook trout implanted with temperature recording tags and subjected to rapid and slow temperature changes Data for examining thermal equilibration rates of brook trout implanted with temperature recording tags and subjected to rapid and slow temperature changes
Brook trout abundance in streams across southern Appalachia from 1958-2021 Brook trout abundance in streams across southern Appalachia from 1958-2021
West Brook Trout Data, Whatley, Massachusetts. West Brook Trout Data, Whatley, Massachusetts.
Brook trout imagery data for individual recognition with deep learning Brook trout imagery data for individual recognition with deep learning
USGS EcoDrought Stream Discharge, Gage Height, and Water Temperature in Shenandoah National Park, Virginia USGS EcoDrought Stream Discharge, Gage Height, and Water Temperature in Shenandoah National Park, Virginia
USGS EcoDrought Stream Discharge, Gage Height and Water Temperature Data in Massachusetts (ver. 2.0, February 2025) USGS EcoDrought Stream Discharge, Gage Height and Water Temperature Data in Massachusetts (ver. 2.0, February 2025)
Annotated fish imagery data for individual and species recognition with deep learning Annotated fish imagery data for individual and species recognition with deep learning
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).

Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).

Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
How quickly do brook trout lose long-term thermal acclimation? How quickly do brook trout lose long-term thermal acclimation?
A low-cost approach to monitoring streamflow dynamics in small, headwater streams using timelapse imagery and a deep learning model A low-cost approach to monitoring streamflow dynamics in small, headwater streams using timelapse imagery and a deep learning model
A new genomic resource to enable standardized surveys of SNPs across the native range of brook trout (Salvelinus fontinalis) A new genomic resource to enable standardized surveys of SNPs across the native range of brook trout (Salvelinus fontinalis)
Thermal transfer rate is slower in bigger fish: How does body size affect response time of small, implantable temperature recording tags? Thermal transfer rate is slower in bigger fish: How does body size affect response time of small, implantable temperature recording tags?
Updates to the Flow Photo Explorer tool Updates to the Flow Photo Explorer tool
Strong variation in Brook Trout trends across geology, elevation, and stream size in Shenandoah National Park Strong variation in Brook Trout trends across geology, elevation, and stream size in Shenandoah National Park
Smaller body size under warming is not due to gill-oxygen limitation in a coldwater salmonid Smaller body size under warming is not due to gill-oxygen limitation in a coldwater salmonid
Aging contrast: A contrastive learning framework for fish re-identification across seasons and years. Aging contrast: A contrastive learning framework for fish re-identification across seasons and years.
Spatial asynchrony and cross-scale climate interactions in populations of a coldwater stream fish Spatial asynchrony and cross-scale climate interactions in populations of a coldwater stream fish
CGS: Coupled growth and survival model with cohort fairness CGS: Coupled growth and survival model with cohort fairness
Closing the gap between science and management of cold-water refuges in rivers and streams Closing the gap between science and management of cold-water refuges in rivers and streams
Community for data integration 2019 project report Community for data integration 2019 project report
Interactive Catchment Explorer (ICE) Interactive Catchment Explorer (ICE)
Flow Photo Explorer Flow Photo Explorer
EcoSHEDS EcoSHEDS
Streamflow Rank Estimation (SRE) Model Streamflow Rank Estimation (SRE) Model
Ecosheds.org Ecosheds.org
Science and Products
Brook trout vulnerability to drought: eastern component of USGS national integrated ecohydrological research
Integrating Streamflow and Temperature to Identify Streams with Coldwater Refugia in the Northeast
Enabling AI for citizen science in fish biology
Enhancing Water Temperature Monitoring Efforts across Alaska through Collaborative Leveraging of a Statewide Database
North Atlantic-Appalachian AI/ML Capabilities
Enabling AI for citizen science in fish ecology
Understanding Brook Trout Persistence in Warming Streams
Scoping the Feasibility of Incorporating Climate Change into Risk Assessments of Aquatic Invasive Species in the Upper Midwest
Brook Trout Population Responses to Climate Variation Across the Southeast USA
A generic web application to visualize and understand movements of tagged animals
Climate change forecasts for eastern salmonids
The West Brook Story
Longer exposure to warm water increases subsequent thermal tolerance of brook trout in cold water: acclimation timing and physiology Longer exposure to warm water increases subsequent thermal tolerance of brook trout in cold water: acclimation timing and physiology
Passive integrated transponder tag data from Sawmill River, Catamaran Brook and Shorey Brook Passive integrated transponder tag data from Sawmill River, Catamaran Brook and Shorey Brook
Model Predictions, Observations, and Annotation Data for Deep Learning Models Developed to Estimate Relative Flow at 11 Massachusetts Streamflow Sites, 2017-2024 Model Predictions, Observations, and Annotation Data for Deep Learning Models Developed to Estimate Relative Flow at 11 Massachusetts Streamflow Sites, 2017-2024
Loss of acclimation response of brook trout acclimated to three thermal regimes for 2-years and then moved to a common colder temperature Loss of acclimation response of brook trout acclimated to three thermal regimes for 2-years and then moved to a common colder temperature
Passive integrated transponder tag data from the West Brook, MA, USA Passive integrated transponder tag data from the West Brook, MA, USA
Data for examining thermal equilibration rates of brook trout implanted with temperature recording tags and subjected to rapid and slow temperature changes Data for examining thermal equilibration rates of brook trout implanted with temperature recording tags and subjected to rapid and slow temperature changes
Brook trout abundance in streams across southern Appalachia from 1958-2021 Brook trout abundance in streams across southern Appalachia from 1958-2021
West Brook Trout Data, Whatley, Massachusetts. West Brook Trout Data, Whatley, Massachusetts.
Brook trout imagery data for individual recognition with deep learning Brook trout imagery data for individual recognition with deep learning
USGS EcoDrought Stream Discharge, Gage Height, and Water Temperature in Shenandoah National Park, Virginia USGS EcoDrought Stream Discharge, Gage Height, and Water Temperature in Shenandoah National Park, Virginia
USGS EcoDrought Stream Discharge, Gage Height and Water Temperature Data in Massachusetts (ver. 2.0, February 2025) USGS EcoDrought Stream Discharge, Gage Height and Water Temperature Data in Massachusetts (ver. 2.0, February 2025)
Annotated fish imagery data for individual and species recognition with deep learning Annotated fish imagery data for individual and species recognition with deep learning
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).

Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).

Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).
Flow is a critical variable in streams since it affects aquatic and riparian biological communities and human uses of water (i.e., recreation, public water supply, etc.). Flow regimes are changing due to anthropogenic (e.g., water withdrawals) and natural impacts (e.g., extreme weather events).