Collin Eagles-Smith
I am a Research Ecologist with the USGS Forest and Rangeland Ecosystem Science Center in Corvallis, Oregon. My research focuses on the interactions among ecological processes, contaminant bioaccumulation, and effects on wild populations.
My work specifically focuses on (1) the ecological factors regulating contaminant bioaccumulation and trophic transfer, with an emphasis on food web processes and contaminant cycling, (2) land use practices and ecosystem restoration effects on contaminant cycling through food webs, and (3) the sublethal effects of contaminants on individuals and contaminant-induced impairment to reproduction in the wild. My research is broadly applied across taxa - primarily fish and waterbirds, and habitat types - including lakes, freshwater wetlands, agricultural fields, and estuarine habitats.
Professional Experience
2010-present: Supervisory Research Ecologist, USGS Forest and Rangeland Ecosystem Science Center, Corvallis, OR
2007-2010: Wildlife Biologist, USGS Western Ecological Research Center, Davis, CA
2003-2007: Biologist, U.S. Fish and Wildlife Service, Sacramento, CA
Education and Certifications
Ph.D., Ecology, University of California, Davis, CA (2006)
B.S., Environmental Resource Sciences - Magna Cum Laude, University of California, Davis, CA (2000)
Science and Products
Contaminant Ecology Research Team (FRESC)
Healthy Fish and Wildlife: Community Livelihoods, Fishing and Hunting Heritage, Recreation, and Economic Security
Prey Availability
Wildfires Increase Mercury Concentrations in Headwater Streams
The Dragonfly Mercury Project
Ecologically-Driven Exposure Pathways Science Team
Scientists Provide an Understanding of Anticoagulant Rodenticide Exposure in Non-Target Bird Species
Nationwide Occurrence
Bioaccumulation of Mercury in Fish Varied by Species and Location in the Chesapeake Bay Watershed—Summary of Existing Data and a Roadmap for Integrated Monitoring
Dragonfly Larvae are Effective Bioindicators of Mercury Exposure in Fish and Amphibians—Results of Citizen Science in 100 National Parks and Protected Places
Roadmap to Understanding Factors Influencing Mercury Exposure and Adverse Health Effects
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
Ecosystem Effects of Increased Coal Transport Across the Pacific Northwest
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Aquatic invertebrate and crustacean community structure, densities, and dry masses within Great Basin terminal lakes in California, Nevada, Oregon, and Utah 2024 and 2025 Aquatic invertebrate and crustacean community structure, densities, and dry masses within Great Basin terminal lakes in California, Nevada, Oregon, and Utah 2024 and 2025
Concentrations of per-and polyfluoroalkyl substances (PFAS) in dragonfly larvae and water collected from National Park Service lands, U.S. Fish and Wildlife Service refuges, and Tribal lands across the continental United States, 2021-24 Concentrations of per-and polyfluoroalkyl substances (PFAS) in dragonfly larvae and water collected from National Park Service lands, U.S. Fish and Wildlife Service refuges, and Tribal lands across the continental United States, 2021-24
Total mercury and methylmercury concentrations in biota collected from the Columbia River Basin, USA Total mercury and methylmercury concentrations in biota collected from the Columbia River Basin, USA
Water Quality of Terminal Lakes Across the Great Basin of the Western United States, 2023 – 2026 Water Quality of Terminal Lakes Across the Great Basin of the Western United States, 2023 – 2026
Ecosystem Metabolism Data for Brownlee Reservoir, Snake River, Idaho/Oregon, 2017-2023 Ecosystem Metabolism Data for Brownlee Reservoir, Snake River, Idaho/Oregon, 2017-2023
Total mercury and methylmercury concentrations in biota from the Hells Canyon Reservoir Complex on the Snake River, Idaho and Oregon, USA Total mercury and methylmercury concentrations in biota from the Hells Canyon Reservoir Complex on the Snake River, Idaho and Oregon, USA
Mercury concentrations in amphibian tissues and egg masses, fish tissues and sediment in subarctic, freshwater systems near Churchill, Manitoba, 2015-2019 Mercury concentrations in amphibian tissues and egg masses, fish tissues and sediment in subarctic, freshwater systems near Churchill, Manitoba, 2015-2019
Total mercury concentrations in bat tissues and blood from southwestern U.S. National Parks in 2023 Total mercury concentrations in bat tissues and blood from southwestern U.S. National Parks in 2023
Mercury in biota from Clear Lake, California (ver. 4.0, April 2026) Mercury in biota from Clear Lake, California (ver. 4.0, April 2026)
Mercury in soil, water, sediment, and biota in headwater streams associated with wildfires in the northwestern U.S., 2021-2022 Mercury in soil, water, sediment, and biota in headwater streams associated with wildfires in the northwestern U.S., 2021-2022
Mercury concentrations in dragonfly larvae from the Willamette River Basin, 2023 Mercury concentrations in dragonfly larvae from the Willamette River Basin, 2023
Mercury Stable Isotope Assessment of Dragonflies and Fish Tissues across United States National Parks Mercury Stable Isotope Assessment of Dragonflies and Fish Tissues across United States National Parks
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Non-destructive sampling of larval amphibians shows tail tissues reflect whole-body methylmercury concentrations and trophic-related differences in bioaccumulation Non-destructive sampling of larval amphibians shows tail tissues reflect whole-body methylmercury concentrations and trophic-related differences in bioaccumulation
Decoupling the roles of corticosterone in mediating effects of methylmercury and chytrid fungus on amphibian survival Decoupling the roles of corticosterone in mediating effects of methylmercury and chytrid fungus on amphibian survival
The effects of forest harvesting on total and methylmercury concentrations in surface waters depend on harvest practices and physical site characteristics The effects of forest harvesting on total and methylmercury concentrations in surface waters depend on harvest practices and physical site characteristics
Independent and interactive effects of disease and methylmercury on demographic rates across multiple amphibian populations Independent and interactive effects of disease and methylmercury on demographic rates across multiple amphibian populations
Climate-driven deoxygenation of lakes alters the nutrient-toxin profile of a food fish Climate-driven deoxygenation of lakes alters the nutrient-toxin profile of a food fish
Sampling dragonflies for mercury analysis in Grand Canyon National Park, 2018–2024: A contribution of the Dragonfly Mercury Project Sampling dragonflies for mercury analysis in Grand Canyon National Park, 2018–2024: A contribution of the Dragonfly Mercury Project
Selenium differentially influences methylmercury retention across mayfly life stages Selenium differentially influences methylmercury retention across mayfly life stages
Mercury trophic transfer to a freshwater biosentinel: Quantifying controlled bioaccumulation in larval dragonflies Mercury trophic transfer to a freshwater biosentinel: Quantifying controlled bioaccumulation in larval dragonflies
Contrasting magnitude and timing of pulsed aqueous methylmercury bioaccumulation across a reservoir food web Contrasting magnitude and timing of pulsed aqueous methylmercury bioaccumulation across a reservoir food web
Ecosystem drivers of freshwater mercury bioaccumulation are context-dependent: Insights from continental-scale modeling Ecosystem drivers of freshwater mercury bioaccumulation are context-dependent: Insights from continental-scale modeling
Methylmercury in subarctic amphibians: Environmental gradients, bioaccumulation, and estimated flux Methylmercury in subarctic amphibians: Environmental gradients, bioaccumulation, and estimated flux
Imperiled Great Basin terminal lakes: Synthesizing ecological and hydrological science gaps and research needs for waterbird conservation Imperiled Great Basin terminal lakes: Synthesizing ecological and hydrological science gaps and research needs for waterbird conservation
Non-USGS Publications**
**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.
To request an interview, contact fresc_outreach@usgs.gov or call (541) 750-1030.
Science and Products
Contaminant Ecology Research Team (FRESC)
Healthy Fish and Wildlife: Community Livelihoods, Fishing and Hunting Heritage, Recreation, and Economic Security
Prey Availability
Wildfires Increase Mercury Concentrations in Headwater Streams
The Dragonfly Mercury Project
Ecologically-Driven Exposure Pathways Science Team
Scientists Provide an Understanding of Anticoagulant Rodenticide Exposure in Non-Target Bird Species
Nationwide Occurrence
Bioaccumulation of Mercury in Fish Varied by Species and Location in the Chesapeake Bay Watershed—Summary of Existing Data and a Roadmap for Integrated Monitoring
Dragonfly Larvae are Effective Bioindicators of Mercury Exposure in Fish and Amphibians—Results of Citizen Science in 100 National Parks and Protected Places
Roadmap to Understanding Factors Influencing Mercury Exposure and Adverse Health Effects
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
Ecosystem Effects of Increased Coal Transport Across the Pacific Northwest
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Aquatic invertebrate and crustacean community structure, densities, and dry masses within Great Basin terminal lakes in California, Nevada, Oregon, and Utah 2024 and 2025 Aquatic invertebrate and crustacean community structure, densities, and dry masses within Great Basin terminal lakes in California, Nevada, Oregon, and Utah 2024 and 2025
Concentrations of per-and polyfluoroalkyl substances (PFAS) in dragonfly larvae and water collected from National Park Service lands, U.S. Fish and Wildlife Service refuges, and Tribal lands across the continental United States, 2021-24 Concentrations of per-and polyfluoroalkyl substances (PFAS) in dragonfly larvae and water collected from National Park Service lands, U.S. Fish and Wildlife Service refuges, and Tribal lands across the continental United States, 2021-24
Total mercury and methylmercury concentrations in biota collected from the Columbia River Basin, USA Total mercury and methylmercury concentrations in biota collected from the Columbia River Basin, USA
Water Quality of Terminal Lakes Across the Great Basin of the Western United States, 2023 – 2026 Water Quality of Terminal Lakes Across the Great Basin of the Western United States, 2023 – 2026
Ecosystem Metabolism Data for Brownlee Reservoir, Snake River, Idaho/Oregon, 2017-2023 Ecosystem Metabolism Data for Brownlee Reservoir, Snake River, Idaho/Oregon, 2017-2023
Total mercury and methylmercury concentrations in biota from the Hells Canyon Reservoir Complex on the Snake River, Idaho and Oregon, USA Total mercury and methylmercury concentrations in biota from the Hells Canyon Reservoir Complex on the Snake River, Idaho and Oregon, USA
Mercury concentrations in amphibian tissues and egg masses, fish tissues and sediment in subarctic, freshwater systems near Churchill, Manitoba, 2015-2019 Mercury concentrations in amphibian tissues and egg masses, fish tissues and sediment in subarctic, freshwater systems near Churchill, Manitoba, 2015-2019
Total mercury concentrations in bat tissues and blood from southwestern U.S. National Parks in 2023 Total mercury concentrations in bat tissues and blood from southwestern U.S. National Parks in 2023
Mercury in biota from Clear Lake, California (ver. 4.0, April 2026) Mercury in biota from Clear Lake, California (ver. 4.0, April 2026)
Mercury in soil, water, sediment, and biota in headwater streams associated with wildfires in the northwestern U.S., 2021-2022 Mercury in soil, water, sediment, and biota in headwater streams associated with wildfires in the northwestern U.S., 2021-2022
Mercury concentrations in dragonfly larvae from the Willamette River Basin, 2023 Mercury concentrations in dragonfly larvae from the Willamette River Basin, 2023
Mercury Stable Isotope Assessment of Dragonflies and Fish Tissues across United States National Parks Mercury Stable Isotope Assessment of Dragonflies and Fish Tissues across United States National Parks
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Non-destructive sampling of larval amphibians shows tail tissues reflect whole-body methylmercury concentrations and trophic-related differences in bioaccumulation Non-destructive sampling of larval amphibians shows tail tissues reflect whole-body methylmercury concentrations and trophic-related differences in bioaccumulation
Decoupling the roles of corticosterone in mediating effects of methylmercury and chytrid fungus on amphibian survival Decoupling the roles of corticosterone in mediating effects of methylmercury and chytrid fungus on amphibian survival
The effects of forest harvesting on total and methylmercury concentrations in surface waters depend on harvest practices and physical site characteristics The effects of forest harvesting on total and methylmercury concentrations in surface waters depend on harvest practices and physical site characteristics
Independent and interactive effects of disease and methylmercury on demographic rates across multiple amphibian populations Independent and interactive effects of disease and methylmercury on demographic rates across multiple amphibian populations
Climate-driven deoxygenation of lakes alters the nutrient-toxin profile of a food fish Climate-driven deoxygenation of lakes alters the nutrient-toxin profile of a food fish
Sampling dragonflies for mercury analysis in Grand Canyon National Park, 2018–2024: A contribution of the Dragonfly Mercury Project Sampling dragonflies for mercury analysis in Grand Canyon National Park, 2018–2024: A contribution of the Dragonfly Mercury Project
Selenium differentially influences methylmercury retention across mayfly life stages Selenium differentially influences methylmercury retention across mayfly life stages
Mercury trophic transfer to a freshwater biosentinel: Quantifying controlled bioaccumulation in larval dragonflies Mercury trophic transfer to a freshwater biosentinel: Quantifying controlled bioaccumulation in larval dragonflies
Contrasting magnitude and timing of pulsed aqueous methylmercury bioaccumulation across a reservoir food web Contrasting magnitude and timing of pulsed aqueous methylmercury bioaccumulation across a reservoir food web
Ecosystem drivers of freshwater mercury bioaccumulation are context-dependent: Insights from continental-scale modeling Ecosystem drivers of freshwater mercury bioaccumulation are context-dependent: Insights from continental-scale modeling
Methylmercury in subarctic amphibians: Environmental gradients, bioaccumulation, and estimated flux Methylmercury in subarctic amphibians: Environmental gradients, bioaccumulation, and estimated flux
Imperiled Great Basin terminal lakes: Synthesizing ecological and hydrological science gaps and research needs for waterbird conservation Imperiled Great Basin terminal lakes: Synthesizing ecological and hydrological science gaps and research needs for waterbird conservation
Non-USGS Publications**
**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.
To request an interview, contact fresc_outreach@usgs.gov or call (541) 750-1030.