Josh T Ackerman | U.S. Geological Survey

Josh T Ackerman | U.S. Geological Survey
Official websites use .gov
.gov
website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
lock (
or
means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Josh T Ackerman
Research Wildlife Biologist
Western Ecological Research Center (WERC)
Email
jackerman@usgs.gov
Phone
530-669-5087
0000-0002-3074-8322
Expertise
bird ecology
ecotoxicology
wildlife population management
aquatic ecosystems
wildlife
migratory species
ecosystems
wetland ecosystems
contamination and pollution
water quality
nonpoint-source pollution
risk assessment
ecological processes
habitat alteration
human impacts
field methods
laboratory methods
toxic trace element contamination
plant and animal testing
invertebrates
vertebrates
capturing (animals)
animals
coastal ecosystems
marine water quality
habitats
freshwater ecosystems
estuarine ecosystems
migration (organisms)
surface water quality
bioaccumulation
avian ecology
Dr. Ackerman is a Principal Investigator with USGS and an Associate in the Department of Wildlife, Fish, and Conservation Biology at the University of California-Davis.
Avian mercury exposure and toxicological risk across western North America: A synthesis
Mercury contamination of birds is prevalent in many areas throughout western North America, and large-scale ecological attributes are important factors influencing bird mercury concentrations. This report synthesizes the available data on mercury contamination of birds in western North America.
Read the Report
Development of methylmercury toxicity reference values in birds
Birds are used as bioindicators of environmental mercury contamination, and toxicity reference values are needed for injury assessments. We conducted a comprehensive review, summarized data from 168 studies, performed a series of meta-analyses, and developed new toxicity reference values for the effects of methylmercury on birds.
See the Toxicity Values
Waterfowl Research
Breeding and Wintering Ecology of Waterfowl
Waterfowl Ecology in Suisun Marsh and the Pacific Flyway
Re-establishing Waterbird Breeding Colonies in San Francisco Bay
Josh's research expertise is in wildlife ecology and ecotoxicology, and his research program focuses on bird ecology, wetland management and restoration, contaminant bioaccumulation in fish and wildlife, and effects of contaminants on animal health and populations.
Professional Experience
Research Wildlife Biologist
, U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, California (2006-present)
Wildlife Biologist
, U.S. Geological Survey, Western Ecological Research Center, San Francisco Bay Estuary Field Station, Vallejo, California (2004-2006)
Post-doctoral Researcher
, John Muir Institute of the Environment, University of California-Davis (2003-2004)
Post-doctoral Researcher
, Dept. of Wildlife, Fish, and Conservation Biology, University of California-Davis (2002-2003)
Teaching Assistant
, Ecology and Management of Waterfowl and Game Birds (Spring 2002) and Field Methods in Wildlife, Fish, and Conservation Biology (Summer 2001), Dept. of Wildlife, Fish, and Conservation Biology, University of California-Davis
Waterfowl Researcher
(1999-2000),
Crew Leader
(Spring 1998, 1999, 2000), and
Technician
(Spring 1997), California Waterfowl Association, Sacramento, California
Doctoral Research
, Dept. of Wildlife, Fish, and Conservation Biology, University of California-Davis (1997-2002)
Biological Technician
(Summer 1995) and
Biological Aid
(Summer 1994), U.S. Forest Service, Tahoe National Forest, Nevada City, California
Education and Certifications
Ph.D. 2002,
Ecology
, University of California-Davis
B.S. 1997 (Magna Cum Laude),
Wildlife, Fish, and Conservation Biology
, University of California-Davis
Science and Products
Science
Data
Multimedia
Publications
Web Tools
Software
News
Filter Total Items: 20
January 28, 2026
Tackling avian influenza with automated detection for an early warning system
The USGS is collaborating with agricultural and wildlife management partners to address the threat of highly-pathogenic avian influenza (HPAI) to wildlife, domestic poultry, and livestock. Partners include federal (U.S. Fish and Wildlife Service and U.S. Department of Agriculture) and non-federal agencies as well as State government, private organizations, and academic institutions. Our...
By
Ecosystems Mission Area
Biological Threats and Invasive Species Research Program
Eastern Ecological Science Center
Western Ecological Research Center (WERC)
Tackling avian influenza with automated detection for an early warning system
January 28, 2026
Tackling avian influenza with automated detection for an early warning system
The USGS is collaborating with agricultural and wildlife management partners to address the threat of highly-pathogenic avian influenza (HPAI) to wildlife, domestic poultry, and livestock. Partners include federal (U.S. Fish and Wildlife Service and U.S. Department of Agriculture) and non-federal agencies as well as State government, private organizations, and academic institutions. Our...
July 23, 2025
Healthy Fish and Wildlife: Community Livelihoods, Fishing and Hunting Heritage, Recreation, and Economic Security
Healthy fish and wildlife underpin the economic vitality, food security, recreational enjoyment, and cultural heritage of fishing and hunting in communities across the United States. Fishing and hunting resources scale from the personal recreation of families to multi-billion-dollar industries. Recognizing these critical connections, the U.S. Geological Survey (USGS) works to understand, protect...
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
California Water Science Center
Central Midwest Water Science Center
Columbia Environmental Research Center
Eastern Ecological Science Center
Forest and Rangeland Ecosystem Science Center
Upper Midwest Environmental Sciences Center
Upper Midwest Water Science Center
Healthy Fish and Wildlife: Community Livelihoods, Fishing and Hunting Heritage, Recreation, and Economic Security
July 23, 2025
Healthy Fish and Wildlife: Community Livelihoods, Fishing and Hunting Heritage, Recreation, and Economic Security
Healthy fish and wildlife underpin the economic vitality, food security, recreational enjoyment, and cultural heritage of fishing and hunting in communities across the United States. Fishing and hunting resources scale from the personal recreation of families to multi-billion-dollar industries. Recognizing these critical connections, the U.S. Geological Survey (USGS) works to understand, protect...
July 5, 2024
Estimating Methylmercury Injury to Birds—“The Bird Mercury Tool”
U.S. Geological Survey (USGS) scientists have developed a tool that can be used by practitioners to help interpret injury to birds caused by methylmercury contamination. This tool was developed from a comprehensive review of 168 studies and summarizing data on the effects of methylmercury on birds.
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
Western Ecological Research Center (WERC)
Estimating Methylmercury Injury to Birds—“The Bird Mercury Tool”
July 5, 2024
Estimating Methylmercury Injury to Birds—“The Bird Mercury Tool”
U.S. Geological Survey (USGS) scientists have developed a tool that can be used by practitioners to help interpret injury to birds caused by methylmercury contamination. This tool was developed from a comprehensive review of 168 studies and summarizing data on the effects of methylmercury on birds.
November 3, 2022
Avian Influenza Prevalence Correlated to Mercury Concentrations in Wild Waterfowl
Low pathogenic avian influenza infections were directly correlated with blood mercury concentrations in wild waterfowl, indicating that mercury exposure may be related to pathogen susceptibility. Further study is needed to determine if and how mercury and other environmental contaminant exposures may affect disease susceptibility in wildlife.
By
Ecosystems Mission Area
Environmental Health Program
Avian Influenza Prevalence Correlated to Mercury Concentrations in Wild Waterfowl
November 3, 2022
Avian Influenza Prevalence Correlated to Mercury Concentrations in Wild Waterfowl
Low pathogenic avian influenza infections were directly correlated with blood mercury concentrations in wild waterfowl, indicating that mercury exposure may be related to pathogen susceptibility. Further study is needed to determine if and how mercury and other environmental contaminant exposures may affect disease susceptibility in wildlife.
July 12, 2021
Ecologically-Driven Exposure Pathways Science Team
The Ecologically-Driven Exposure Pathways Integrated Science Team identifies how ecological pathways and physiological processes within a single organism can alter exposure and toxicity of contaminants and pathogens and seek to understand outcomes at different scales from individuals to populations and ecosystems.
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Ecologically-Driven Exposure Pathways Science Team
July 12, 2021
Ecologically-Driven Exposure Pathways Science Team
The Ecologically-Driven Exposure Pathways Integrated Science Team identifies how ecological pathways and physiological processes within a single organism can alter exposure and toxicity of contaminants and pathogens and seek to understand outcomes at different scales from individuals to populations and ecosystems.
February 17, 2021
Wetland Management Technique Designed to Reduce Mercury in Water and Fish Tested During a Short-Term Field Study
Results from a 3-year study indicate there was support for the use of open- and deep-water treatment pools at the downstream end of seasonal wetlands to reduce methylmercury concentrations in water exported from the wetlands, but the treatment had no measurable effect on wetland fish. Questions remain about the long-term potential for mercury removal using this wetland management strategy.
By
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
Wetland Management Technique Designed to Reduce Mercury in Water and Fish Tested During a Short-Term Field Study
February 17, 2021
Wetland Management Technique Designed to Reduce Mercury in Water and Fish Tested During a Short-Term Field Study
Results from a 3-year study indicate there was support for the use of open- and deep-water treatment pools at the downstream end of seasonal wetlands to reduce methylmercury concentrations in water exported from the wetlands, but the treatment had no measurable effect on wetland fish. Questions remain about the long-term potential for mercury removal using this wetland management strategy.
October 4, 2019
Science to Help Understand Exposure and Toxicological Effects of Environmental Mercury to Representative Birds
Exposure and toxicity of environmental mercury to birds can be enhanced or lessened due to the available sources and forms of mercury and other species dependent factors such as life stage, migratory patterns, foraging and nesting behaviors, transfer of mercury from mothers to eggs, and sex. For example, mercury exposure can lead to sublethal toxicological effects that can influence parental...
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
Science to Help Understand Exposure and Toxicological Effects of Environmental Mercury to Representative Birds
October 4, 2019
Science to Help Understand Exposure and Toxicological Effects of Environmental Mercury to Representative Birds
Exposure and toxicity of environmental mercury to birds can be enhanced or lessened due to the available sources and forms of mercury and other species dependent factors such as life stage, migratory patterns, foraging and nesting behaviors, transfer of mercury from mothers to eggs, and sex. For example, mercury exposure can lead to sublethal toxicological effects that can influence parental...
June 30, 2018
Suisun Marsh Waterfowl and Wildlife Studies
Suisun Marsh provides critical habitat for wintering and breeding waterbirds in California. USGS WERC collaborates with the California Department of Water Resources to examine trends in bird declines and to assess the habitat factors driving long-term survival of waterfowl, rails, and other birds in this important area.
By
Western Ecological Research Center (WERC)
Suisun Marsh Waterfowl and Wildlife Studies
June 30, 2018
Suisun Marsh Waterfowl and Wildlife Studies
Suisun Marsh provides critical habitat for wintering and breeding waterbirds in California. USGS WERC collaborates with the California Department of Water Resources to examine trends in bird declines and to assess the habitat factors driving long-term survival of waterfowl, rails, and other birds in this important area.
June 6, 2018
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
In a study designed to help resource managers when considering mercury exposure risk, scientists determined that sulfur cycling—a process closely related to mercury methylation rates—and ecological conditions that influence exposure are important factors affecting fish mercury concentrations in estuarine wetlands.
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
June 6, 2018
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
In a study designed to help resource managers when considering mercury exposure risk, scientists determined that sulfur cycling—a process closely related to mercury methylation rates—and ecological conditions that influence exposure are important factors affecting fish mercury concentrations in estuarine wetlands.
May 18, 2018
New Method Can Measure Naturally Occurring Element Exposure in Hummingbirds Without Harm
Seventeen naturally occurring trace elements, including those associated with adverse health impacts when birds are exposed to toxic levels (iron, lead, mercury, selenium, zinc, cadmium, and arsenic) were measured in small birds without harm. The nonlethal method was developed for hummingbirds, with Anna's hummingbirds ( Calypte anna) as a test species and can be more broadly applied to other...
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
New Method Can Measure Naturally Occurring Element Exposure in Hummingbirds Without Harm
May 18, 2018
New Method Can Measure Naturally Occurring Element Exposure in Hummingbirds Without Harm
Seventeen naturally occurring trace elements, including those associated with adverse health impacts when birds are exposed to toxic levels (iron, lead, mercury, selenium, zinc, cadmium, and arsenic) were measured in small birds without harm. The nonlethal method was developed for hummingbirds, with Anna's hummingbirds ( Calypte anna) as a test species and can be more broadly applied to other...
October 30, 2017
Waterfowl Ecology in California and the Pacific Flyway
The Suisun Marsh and Central Valley in California offer some of the world’s most important wetland habitats for waterfowl in the Pacific Flyway. Mike Casazza and USGS WERC biologists are providing the science to support and evaluate waterfowl populations and habitat management in North America.
By
Ecosystems Mission Area
Species Management Research Program
Western Ecological Research Center (WERC)
Waterfowl Ecology in California and the Pacific Flyway
October 30, 2017
Waterfowl Ecology in California and the Pacific Flyway
The Suisun Marsh and Central Valley in California offer some of the world’s most important wetland habitats for waterfowl in the Pacific Flyway. Mike Casazza and USGS WERC biologists are providing the science to support and evaluate waterfowl populations and habitat management in North America.
October 30, 2017
Waterbird Breeding Ecology and Management
The San Francisco Bay is designated as a site of hemispheric importance to shorebirds and annually supports over one million waterbirds. Within the USGS WERC waterbird breeding ecology program, Dr. Josh Ackerman and partners are studying habitat selection, movements, and factors influencing waterbird nest success and chick growth and survival.
By
Ecosystems Mission Area
Land Management Research Program
Species Management Research Program
Western Ecological Research Center (WERC)
Waterbird Breeding Ecology and Management
October 30, 2017
Waterbird Breeding Ecology and Management
The San Francisco Bay is designated as a site of hemispheric importance to shorebirds and annually supports over one million waterbirds. Within the USGS WERC waterbird breeding ecology program, Dr. Josh Ackerman and partners are studying habitat selection, movements, and factors influencing waterbird nest success and chick growth and survival.
Filter Total Items: 46
March 5, 2026
American Avocet and Wilson’s Phalarope Locations and Ancillary Data Associated with the U.S. Geological Survey Saline Lake Ecosystems Integrated Water Availability Assessment Program
American Avocet and Wilson’s Phalarope Locations and Ancillary Data Associated with the U.S. Geological Survey Saline Lake Ecosystems Integrated Water Availability Assessment Program
These data describe tracking information and provide location data of American avocets (from 2023-03-18 to 2024-12-31) and Wilson’s phalaropes (from 2023-08-17 to 2023-11-10) collected in support of the U.S. Geological Survey Saline Lakes Ecosystems Integrated Water Availability Assessment Program (USGS SLE IWAA). The data are provided using standardized formats and an attribute...
By
Western Ecological Research Center (WERC)
Saline Lake Ecosystems Integrated Water Availability Assessment
February 27, 2026
Dabbling Duckling Habitat Use and Movements
Dabbling Duckling Habitat Use and Movements
We conducted a multi-year study (2016-2019) to identify elements of wetland habitat management that could potentially benefit breeding ducks. Specifically, we examined the influence of habitat variables in explaining habitat selection of managed wetlands near upland nesting sites by radio-tagged Mallard (Anas platyrhynchos) and Gadwall (Mareca strepera) ducklings in a brackish marsh...
By
Western Ecological Research Center (WERC)
July 15, 2025
Long-term Trends in Spring and Summer-flooded Wetland area in Suisun Marsh, California
Long-term Trends in Spring and Summer-flooded Wetland area in Suisun Marsh, California
We digitized water on the landscape for breeding waterfowl and other wetland-associated species within Suisun Marsh (California, USA) twice each year (spring and summer) during a 38-year period (1984-2021) with remote sensing methods that combined Landsat satellite imagery (composite images) and spectral mixture analysis using Google Earth Engine. This dataset contains the amount of...
By
Western Ecological Research Center (WERC)
July 11, 2025
Nesting Duck Populations in Suisun Marsh, California
Nesting Duck Populations in Suisun Marsh, California
This dataset includes apparent nest density (observed nests per hectare of area searched) of mallard (Anas platyrhynchos) and gadwall (Mareca strepera) in Suisun Marsh, California.
By
Western Ecological Research Center (WERC)
July 11, 2025
Waterbird Nest Abundance in South San Francisco Bay
Waterbird Nest Abundance in South San Francisco Bay
This dataset includes nest abundance of American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), and Forster's terns (Sterna forsteri) in south San Francisco Bay, California by year. It also contains California gull (Larus californicus) hazing research efforts. This dataset was generated from yearly nest monitoring surveys within wetlands in south San...
By
Western Ecological Research Center (WERC)
July 11, 2025
Habitat Features and Waterbird Abundance and Diversity on Managed Wetlands Enrolled in the California Waterfowl Habitat Program
Habitat Features and Waterbird Abundance and Diversity on Managed Wetlands Enrolled in the California Waterfowl Habitat Program
This dataset includes wetland habitat measurements, surrounding land cover metrics, and waterbird abundance and diversity during 240 surveys of 117 individual wetland units enrolled in the California Waterfowl Habitat Program. This dataset was generated from wetland surveys conducted in the Sacramento Valley, San Joaquin Valley, and Suisun Marsh in 2022 and 2023.
By
Western Ecological Research Center (WERC)
October 1, 2024
Waterfowl Brood Drone Surveys from Suisun, California 2019
Waterfowl Brood Drone Surveys from Suisun, California 2019
Effective waterfowl management relies on the collection of relevant demographic data to inform land management decisions; however, some types of data are difficult to obtain. For waterfowl, brood surveys are difficult to conduct because wetland habitats often obscure ducklings from being visually assessed. Here, we used Unoccupied Aerial Systems (UAS) to assess what wetland habitat...
By
Western Ecological Research Center (WERC)
August 15, 2024
Bird use of Winter-Flooded Rice Fields in the Sacramento Valley, California
Bird use of Winter-Flooded Rice Fields in the Sacramento Valley, California
Bird and habitat surveys were conducted in winter-flooded rice fields in the Sacramento Valley, California, USA during the fall and winters of 2021-2022 (Oct 2021 through February 2022) and 2022-2023 (December 2022 through February 2023). Rice field sampling consisted of (1) a bird survey that was followed by (2) an overall habitat assessment and (3) a more detailed habitat transect...
By
Western Ecological Research Center (WERC)
August 12, 2024
Body Mass of Dabbling and Diving Ducks Harvested in California
Body Mass of Dabbling and Diving Ducks Harvested in California
Body mass data (measured in grams) of dabbling and diving ducks harvested in three regions of California: Sacramento Valley, Suisun Marsh, and San Joaquin Valley during the 2014/2015, 2015/2016, 2016/2017, 2018/2019, and 2019/2020 hunting seasons. In addition to mass, the flattened length of right wing, species, sex, age, and date of harvest were also recorded. These data support the...
By
Western Ecological Research Center (WERC)
May 31, 2024
Timing of Occurrence of Waterfowl in U.S. Counties and Canadian Counties, Boroughs, Census Districts, and Other Populated Area Designations with Modeled Exposure Status to Highly Pathogenic Avian Influenza Virus in 2021-2022
Timing of Occurrence of Waterfowl in U.S. Counties and Canadian Counties, Boroughs, Census Districts, and Other Populated Area Designations with Modeled Exposure Status to Highly Pathogenic Avian Influenza Virus in 2021-2022
This data provides county level occurrence information for all individuals used in modelling potential exposure and spread of highly pathogenic avian influenza (HPAIv) from the 2021-2022 North American outbreak. The data set contains individual identifiers and taxa information, an indicator of exposure, exposure status (Susceptible, Exposed by HPAIv detection in the county, or Exposed by...
By
Western Ecological Research Center (WERC)
May 17, 2024
Duckling Survival in a Brackish Marsh
Duckling Survival in a Brackish Marsh
We conducted a multi-year study (2016-2019) to quantify sources of duckling mortality, identify predator type, and estimate survival rates for Mallard (Anas platyrhynchos) and Gadwall (Mareca strepera) ducklings within Suisun Marsh, California.
By
Western Ecological Research Center (WERC)
May 16, 2024
Egg Mercury Concentration and Egg Size in Two Songbird Species
Egg Mercury Concentration and Egg Size in Two Songbird Species
This dataset includes egg total mercury concentrations, egg total mercury burden, egg length, egg width, predicted egg volume, and predicted fresh wet weight according to egg position in the laying sequence for tree swallow and house wren eggs from the Cache Creek Settling Basin and Cosumnes River Preserve, in California's Central Valley during 2018. These data support the following...
By
Western Ecological Research Center (WERC)
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
March 31, 2017
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Scientists from the USGS Western Ecological Research Center (WERC) are conducting a "social attraction" study for seabirds in the Don Edwards San Francisco Bay National Wildlife Refuge. Historically, this region offered wetland habitats to local wildlife. With the introduction of industrial salt ponds and human development, however, much of this habitat was lost.
By
Ecosystems
Wildlife Program
Western Ecological Research Center (WERC)
Communications and Publishing
March 31, 2017
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Scientists from the USGS Western Ecological Research Center (WERC) are conducting a "social attraction" study for seabirds in the Don Edwards San Francisco Bay National Wildlife Refuge. Historically, this region offered wetland habitats to local wildlife. With the introduction of industrial salt ponds and human development, however, much of this habitat was lost.
By
Ecosystems
Wildlife Program
Western Ecological Research Center (WERC)
Communications and Publishing
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
May 29, 2010
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph showing white-faced ibis nesting at Bear River Migratory Bird Refuge, Great Salt Lake, Utah. U.S.
By
Contaminant Biology
Toxic Substances Hydrology
Environmental Health Program
May 29, 2010
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph showing white-faced ibis nesting at Bear River Migratory Bird Refuge, Great Salt Lake, Utah. U.S.
By
Contaminant Biology
Toxic Substances Hydrology
Environmental Health Program
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
June 3, 2004
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Photo of Foster's Tern (Sterna forsteri) while hunting. Forster’s terns are among the most at-risk wildlife species to mercury toxicity in western North America.
By
Contaminant Biology
Toxic Substances Hydrology
Environmental Health Program
June 3, 2004
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Photo of Foster's Tern (Sterna forsteri) while hunting. Forster’s terns are among the most at-risk wildlife species to mercury toxicity in western North America.
By
Contaminant Biology
Toxic Substances Hydrology
Environmental Health Program
December 23, 2019
Synthesis of maternal transfer of mercury in birds: Implications for altered toxicity risk
Synthesis of maternal transfer of mercury in birds: Implications for altered toxicity risk
Maternal transfer is the predominant route of methylmercury (MeHg) exposure to offspring. We reviewed and synthesized published and unpublished data on maternal transfer of MeHg in birds. Using paired samples of females’ blood (n=564) and their eggs (n=1814) from 26 bird species in 6 taxonomic orders, we conducted a meta-analysis to evaluate whether maternal transfer of MeHg to eggs...
Authors
Joshua T. Ackerman, Mark P. Herzog, David C. Evers, Daniel A. Cristol, Kevin P. Kenow, Gary Heinz, Raphael A Lavoie, Rebecka Brasso, Mark L. Mallory, Jennifer F Provencher, Birgit M Braune, Angela Matz, Joel A. Schmutz, Collin A. Eagles-Smith, Lucas J Savoy, Michael W. Meyer, C. Alex Hartman
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
Filter Total Items: 206
March 5, 2026
Monitoring nesting waterbirds for the South Bay Salt Pond Restoration Project—2024 breeding season
Monitoring nesting waterbirds for the South Bay Salt Pond Restoration Project—2024 breeding season
The San Francisco Bay supports thousands of breeding waterbirds annually and hosts large populations of American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), and Forster’s terns (Sterna forsteri). These three species have relied largely on former commercial salt ponds in south San Francisco Bay, which provide wetland foraging habitat and island nesting...
Authors
Joshua T. Ackerman, C. Alex Hartman, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
January 23, 2026
Waterfowl move less in heterogeneous and human-populated landscapes, with implications for spread of avian influenza viruses
Waterfowl move less in heterogeneous and human-populated landscapes, with implications for spread of avian influenza viruses
Animal movements contribute to the spread of infectious diseases and are driven in part by environmental conditions. We investigated the links among the environment, animal movement, and infectious disease dynamics in waterfowl, which are among the primary wildlife hosts of avian influenza viruses. By combining telemetry data on 4606 individuals from 26 waterfowl species with data on...
Authors
Claire Stewart Teitelbaum, Diann J. Prosser, Joshua T. Ackerman, Sakib Ahmed, A.B.M. Sarowar Alam, Kazi Zenifar Azmiri, Nyambaya Batbayar, Joël Bêty, Abigail Blake-Bradshaw, Dmitrijs Boiko, Nelleke H. Buitendijk, Jeffrey J. Buler, David Cabot, Michael L. Casazza, Bradley S. Cohen, Batmunkh Davaasuren, Sébastien Farau, Jamie Feddersen, John R. Fieberg, Wolfgang Fiedler, Peter Glazov, Larry R. Griffin, Matthieu Guillemain, Heath Hagy, Matthew J. Hardy, Cory Highway, David Hoffman, Tehan Kang, Allison Keever, Jennifer Kilburn, Andrea Kölzsch, Helmut Kruckenberg, Toni Laaksonen, Brian S. Ladman, Hansoo Lee, Siwan Lee, Josée Lefebvre, Pierre Legagneux, Hans Linssen, Jesper Madsen, Nicholas M. Masto, Scott R. McWilliams, Tori Mezebish Quinn, Carl P.J. Mitchell, Axelle Moreau, Gerhard Müskens, Scott Newman, Bart A. Nolet, Rascha J.M. Nuijten, Jay Osenkowski, Cory T. Overton, Antti Piironen, Betty Plaquin, Andrew M. Ramey, Jean Rodrigue, David Rodrigues, Kees H.T. Schreven, Yali Si, Jeffery D. Sullivan, John Takekawa, Philippe J. Thomas, Mariëlle van Toor, Jonas Waldenström, Christopher K. Williams, David W. Wolfson, Fei Xu, Ian G. Brosnan, Susan E.W. De La Cruz
By
Cooperative Research Units
September 18, 2025
Habitat features influencing waterbird use of managed wetlands enrolled in a public-private partnership for land conservation: The California Waterfowl Habitat Program
Habitat features influencing waterbird use of managed wetlands enrolled in a public-private partnership for land conservation: The California Waterfowl Habitat Program
Draining, water diversion, and development have greatly reduced the availability of freshwater wetland habitat around the world, and many remaining wetlands are on private lands. Public–private partnership programs can be an important means for promoting habitat conservation and management on private lands. We investigated bird use of 117 wetlands enrolled in the California Waterfowl...
Authors
C. Alex Hartman, Joshua T. Ackerman, Sarah H. Peterson, Brady Lynn Fettig, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
November 20, 2024
Surveying waterfowl broods in wetlands using aerial drones
Surveying waterfowl broods in wetlands using aerial drones
Effective waterfowl management relies on the collection of relevant demographic data to inform land management decisions; however, some types of data are difficult to obtain. For waterfowl, brood surveys are difficult to conduct because wetland habitats often obscure ducklings from being visually assessed. Here, we used Unoccupied Aerial Systems (UAS) to assess what wetland habitat...
Authors
Desmond Alexander Mackell, Michael L. Casazza, Cory T. Overton, Kevin J. Buffington, Chase M. Freeman, Joshua T. Ackerman, Karen M. Thorne
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
November 20, 2024
Bird habitat value and management priorities of the California Winter Rice Habitat Incentive Program
Bird habitat value and management priorities of the California Winter Rice Habitat Incentive Program
Flooding rice (Oryza sativa) agricultural fields during winter to facilitate rice straw decomposition has mitigated the loss of some of the natural wetlands in California’s Central Valley. We conducted bird surveys in 253 rice checks (2,158 ha) within 177 rice fields in the Sacramento Valley during the fall and winter of 2021-2022 and 2022-2023 to evaluate factors influencing bird use of...
Authors
Sarah H. Peterson, Joshua T. Ackerman, Carley R. Schacter, C. Alex Hartman, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
August 12, 2024
Body mass changes of dabbling and diving ducks wintering in California
Body mass changes of dabbling and diving ducks wintering in California
Bird body mass is often used as an index of body condition and fluctuates throughout the year in response to environmental conditions and avian life-history events. We examined the body mass of 59,572 ducks representing 13 species (7 dabbling duck species and 6 diving duck species) harvested within the 3 regions of the Central Valley in California, USA (Sacramento Valley, Suisun Marsh...
Authors
Mark P. Herzog, Joshua T. Ackerman, Jeffrey D. Kohl, Brady Lynn Fettig, C. Alex Hartman, Sarah H. Peterson, Michael L. Casazza, Joseph P. Fleskes
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
July 18, 2024
Mitigating risk: Predicting H5N1 avian influenza spread with an empirical model of bird movement
Mitigating risk: Predicting H5N1 avian influenza spread with an empirical model of bird movement
Understanding timing and distribution of virus spread is critical to global commercial and wildlife biosecurity management. A highly pathogenic avian influenza virus (HPAIv) global panzootic, affecting ~600 bird and mammal species globally and over 83 million birds across North America (Dec 2023), poses a serious global threat to animals and public health. We combined a large, long-term...
Authors
Fiona McDuie, Cory T. Overton, Austen Lorenz, Elliott Matchett, Andrea Mott, Desmond Alexander Mackell, Joshua T. Ackerman, Susan E.W. De La Cruz, Vijay P. Patil, Diann Prosser, John Y. Takekawa, Dennis L. Orthmeyer, Maurice E. Pitesky, Samuel L. Diaz-Munoz, Brock M. Riggs, Joseph Gendreau, Eric T. Reed, Mark J. Petrie, Chris K. Williams, Jeffrey J. Buler, Matthew J. Hardy, Brian S. Ladman, Pierre Legagneux, Joel Bety, Philippe J. Thomas, Jean Rodrigue, Josee Lefebvre, Michael L. Casazza
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
June 10, 2024
Egg mercury concentration and egg size varies with position in the laying sequence in two songbird species
Egg mercury concentration and egg size varies with position in the laying sequence in two songbird species
In birds, mercury embryotoxicity can occur through the transfer of mercury from the female to her eggs. Maternal transfer of mercury can vary by egg position in the laying sequence, with first-laid eggs often exhibiting greater mercury concentrations than subsequently laid eggs. We studied egg mercury concentration, mercury burden (total amount of mercury in the egg), and egg...
Authors
C. Alex Hartman, Joshua T. Ackerman, Breanne Cooney, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
May 13, 2024
Duckling survival increased with availability of flooded wetland habitat and decreased with salinity concentrations in a brackish marsh
Duckling survival increased with availability of flooded wetland habitat and decreased with salinity concentrations in a brackish marsh
Waterfowl population recruitment is sensitive to duckling survival. We quantified predator types and survival rates for Anas platyrhynchos (Mallard) and Mareca strepera (Gadwall) ducklings in one of the largest brackish water marshes in western North America (Suisun Marsh, California) using 556 radio-tagged ducklings from 284 broods tracked during the 2016 to 2019 breeding seasons...
Authors
Sarah H. Peterson, Joshua T. Ackerman, C. Alex Hartman, Andrew C. Greenawalt, Michael L. Casazza, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
April 29, 2024
Global mercury concentrations in biota: Their use as a basis for a global biomonitoring framework
Global mercury concentrations in biota: Their use as a basis for a global biomonitoring framework
An important provision of the Minamata Convention on Mercury is to monitor and evaluate the effectiveness of the adopted measures and its implementation. Here, we describe for the first time currently available biotic mercury (Hg) data on a global scale to improve the understanding of global efforts to reduce the impact of Hg pollution on people and the environment. Data from the peer...
Authors
David C. Evers, Joshua T. Ackerman, Staffan Akerblom, Dominique Bally, Niladri Basu, Kevin Bishop, Nathalie Bodin, Hans Fredrik Veitberg Braaten, Mark Burton, Paco Bustamante, Celia Y. Chen, John Chetelat, Linroy Christian, Rune Dietz, Paul Drevnick, Collin A. Eagles-Smith, Luis Fernandez, Neil Hammerschlag, Mireille Harmelin-Vivien, Agustin Harte, Eva Kruemmel, Jose Lailson-Brito, Gabriella Medina, Cesar Rodriguez, Iain Stenhouse, Elsie M. Sunderland, Akinori Takeuchi, Timothy Tear, Claudia Vega, Simon Wilson, Pianpian Wu
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Forest and Rangeland Ecosystem Science Center
Western Ecological Research Center (WERC)
April 29, 2024
Methylmercury effects on birds: A review, meta-analysis, and development of toxicity reference values for injury assessment based on tissue residues and diet
Methylmercury effects on birds: A review, meta-analysis, and development of toxicity reference values for injury assessment based on tissue residues and diet
Birds are used as bioindicators of environmental mercury (Hg) contamination, and toxicity reference values are needed for injury assessments. We conducted a comprehensive review, summarized data from 168 studies, performed a series of Bayesian hierarchical meta-analyses, and developed new toxicity reference values for the effects of methylmercury (MeHg) on birds using a benchmark dose...
Authors
Joshua T. Ackerman, Sarah H. Peterson, Mark P. Herzog, Julie L. Yee
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
April 24, 2024
Eggshell membrane thickness and its contribution to total eggshell thickness for 13 waterbird species
Eggshell membrane thickness and its contribution to total eggshell thickness for 13 waterbird species
Eggshell thickness can be an indicator of environmental pollution in wild birds and shell quality in wild and domestic birds, but it is difficult to measure calcite eggshell thickness due to the presence of the adherent outer eggshell membrane. Eggshells of 13 waterbird species were divided in half longitudinally and the outer membrane was removed from one of the halves. Subsequently, we...
Authors
Gary M. Santolo, Sarah H. Peterson, Breanne Cooney, C. Alex Hartman, Mark P. Herzog, Joshua T. Ackerman
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
February 26, 2021
Waterfowl Ecology in Suisun Marsh and the Pacific Flyway
Waterfowl Ecology in Suisun Marsh and the Pacific Flyway
Learn about waterfowl research by scientists at the USGS Western Ecological Research Center.
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
San Francisco Bay and Sacramento-San Joaquin Delta Estuary
April 29, 2024
Methylmercury Effects on Birds: Percent Injury Tool
Methylmercury Effects on Birds: Percent Injury Tool
Welcome to The Bird Mercury Tool website. Please follow the guidance below to download the tool and user guide. The Bird Mercury Tool: Estimating Methylmercury Injury to Birds can be used by practitioners to help interpret injury to birds caused by methylmercury concentrations in bird tissues or diet. The dataset, statistical models, and assumptions used within this tool have been...
By
Western Ecological Research Center (WERC)
Filter Total Items: 21
Helping the California Winter Rice Habitat Incentive Program increase bird use of winter-flooded rice fields
December 29, 2025
Helping the California Winter Rice Habitat Incentive Program increase bird use of winter-flooded rice fields
The Central Valley of California provides important habitat for waterbirds (waterfowl, shorebirds, and wading birds).
Read Article
Duckling survival is higher if nests are closer to wetland habitats flooded during the summer
December 29, 2025
Duckling survival is higher if nests are closer to wetland habitats flooded during the summer
A recent USGS study, in collaboration with the California Department of Fish and Wildlife at the Grizzly Island Wildlife Area, investigates what type...
Read Article
RESEARCH SPOTLIGHT: Understanding Mercury’s Effects on Birds
June 10, 2024
RESEARCH SPOTLIGHT: Understanding Mercury’s Effects on Birds
In a recent study published in Environmental Toxicology and Chemistry, USGS researchers have derived new mercury toxicity reference values and...
Read Article
Re-establishing Waterbird Breeding Colonies in San Francisco Bay
April 17, 2024
Re-establishing Waterbird Breeding Colonies in San Francisco Bay
Learn more about how our partners are using ​science and management to maintain and establish new ​bird ​nesting colonies in support of the South Bay...
Read Article
Research Spotlight: What Habitat Features Make Duck Nests Vulnerable to Raccoons and Striped Skunks?
April 20, 2023
Research Spotlight: What Habitat Features Make Duck Nests Vulnerable to Raccoons and Striped Skunks?
Research by USGS scientists finds that predator-specific behaviors can shape where duck nests are most vulnerable in Suisun Marsh, CA. The findings...
Read Article
Research Spotlight: High Salinity and Limited Wetlands Reduce Duckling Habitat for Waterfowl
October 5, 2021
Research Spotlight: High Salinity and Limited Wetlands Reduce Duckling Habitat for Waterfowl
A new publication by USGS scientists examines wetland availability and salinity in Suisun Marsh, with particular focus on the implications for young...
Read Article
Research Spotlight: New Study Explores Nocturnal Nest Breaks and Predation Events for Dabbling Ducks
August 18, 2021
Research Spotlight: New Study Explores Nocturnal Nest Breaks and Predation Events for Dabbling Ducks
A new study by USGS scientists, in collaboration with the California Department of Water Resources and California Department of Fish and Wildlife...
Read Article
Isotope Fractionation from In Vivo Methylmercury Detoxification in Waterbirds
July 16, 2021
Isotope Fractionation from In Vivo Methylmercury Detoxification in Waterbirds
Animals that are higher on the trophic chain, such as waterbirds that primarily rely on fish, are at risk for ingesting methylmercury in their diet...
Read Article
Research Spotlight: Precise Eggshell Thickness Measurements To Inform Bird Ecology And Mercury Monitoring
February 10, 2021
Research Spotlight: Precise Eggshell Thickness Measurements To Inform Bird Ecology And Mercury Monitoring
In a study published in the journal Ecology and Evolution, USGS biologists provide precise eggshell thickness measurements for 12 species of birds...
Read Article
Research Spotlight: Wetland Habitats and Aquatic Prey May Drive High Hair Mercury Concentrations in Suisun Marsh Raccoons
February 3, 2021
Research Spotlight: Wetland Habitats and Aquatic Prey May Drive High Hair Mercury Concentrations in Suisun Marsh Raccoons
A new study by scientists from USGS in collaboration with the California Department of Water Resources has found that mercury concentrations detected...
Read Article
Research Spotlight: Mercury Exposure in Wild Songbirds Associated with Disrupted Parental Care at the Nest
June 30, 2019
Research Spotlight: Mercury Exposure in Wild Songbirds Associated with Disrupted Parental Care at the Nest
In a study published in the journal Environmental Science and Technology, U.S. Geological Survey biologists report that methylmercury concentrations...
Read Article
Research Spotlight: Ducklings Leave Nests in Early Morning, Suggesting Predator Avoidance
June 12, 2019
Research Spotlight: Ducklings Leave Nests in Early Morning, Suggesting Predator Avoidance
In a study published in the journal Ecology and Evolution, U.S. Geological Survey (USGS) biologists put small cameras next to duck nests to determine...
Read Article
Science and Products
Filter Total Items: 20
January 28, 2026
Tackling avian influenza with automated detection for an early warning system
The USGS is collaborating with agricultural and wildlife management partners to address the threat of highly-pathogenic avian influenza (HPAI) to wildlife, domestic poultry, and livestock. Partners include federal (U.S. Fish and Wildlife Service and U.S. Department of Agriculture) and non-federal agencies as well as State government, private organizations, and academic institutions. Our...
By
Ecosystems Mission Area
Biological Threats and Invasive Species Research Program
Eastern Ecological Science Center
Western Ecological Research Center (WERC)
Tackling avian influenza with automated detection for an early warning system
January 28, 2026
Tackling avian influenza with automated detection for an early warning system
The USGS is collaborating with agricultural and wildlife management partners to address the threat of highly-pathogenic avian influenza (HPAI) to wildlife, domestic poultry, and livestock. Partners include federal (U.S. Fish and Wildlife Service and U.S. Department of Agriculture) and non-federal agencies as well as State government, private organizations, and academic institutions. Our...
July 23, 2025
Healthy Fish and Wildlife: Community Livelihoods, Fishing and Hunting Heritage, Recreation, and Economic Security
Healthy fish and wildlife underpin the economic vitality, food security, recreational enjoyment, and cultural heritage of fishing and hunting in communities across the United States. Fishing and hunting resources scale from the personal recreation of families to multi-billion-dollar industries. Recognizing these critical connections, the U.S. Geological Survey (USGS) works to understand, protect...
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
California Water Science Center
Central Midwest Water Science Center
Columbia Environmental Research Center
Eastern Ecological Science Center
Forest and Rangeland Ecosystem Science Center
Upper Midwest Environmental Sciences Center
Upper Midwest Water Science Center
Healthy Fish and Wildlife: Community Livelihoods, Fishing and Hunting Heritage, Recreation, and Economic Security
July 23, 2025
Healthy Fish and Wildlife: Community Livelihoods, Fishing and Hunting Heritage, Recreation, and Economic Security
Healthy fish and wildlife underpin the economic vitality, food security, recreational enjoyment, and cultural heritage of fishing and hunting in communities across the United States. Fishing and hunting resources scale from the personal recreation of families to multi-billion-dollar industries. Recognizing these critical connections, the U.S. Geological Survey (USGS) works to understand, protect...
July 5, 2024
Estimating Methylmercury Injury to Birds—“The Bird Mercury Tool”
U.S. Geological Survey (USGS) scientists have developed a tool that can be used by practitioners to help interpret injury to birds caused by methylmercury contamination. This tool was developed from a comprehensive review of 168 studies and summarizing data on the effects of methylmercury on birds.
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
Western Ecological Research Center (WERC)
Estimating Methylmercury Injury to Birds—“The Bird Mercury Tool”
July 5, 2024
Estimating Methylmercury Injury to Birds—“The Bird Mercury Tool”
U.S. Geological Survey (USGS) scientists have developed a tool that can be used by practitioners to help interpret injury to birds caused by methylmercury contamination. This tool was developed from a comprehensive review of 168 studies and summarizing data on the effects of methylmercury on birds.
November 3, 2022
Avian Influenza Prevalence Correlated to Mercury Concentrations in Wild Waterfowl
Low pathogenic avian influenza infections were directly correlated with blood mercury concentrations in wild waterfowl, indicating that mercury exposure may be related to pathogen susceptibility. Further study is needed to determine if and how mercury and other environmental contaminant exposures may affect disease susceptibility in wildlife.
By
Ecosystems Mission Area
Environmental Health Program
Avian Influenza Prevalence Correlated to Mercury Concentrations in Wild Waterfowl
November 3, 2022
Avian Influenza Prevalence Correlated to Mercury Concentrations in Wild Waterfowl
Low pathogenic avian influenza infections were directly correlated with blood mercury concentrations in wild waterfowl, indicating that mercury exposure may be related to pathogen susceptibility. Further study is needed to determine if and how mercury and other environmental contaminant exposures may affect disease susceptibility in wildlife.
July 12, 2021
Ecologically-Driven Exposure Pathways Science Team
The Ecologically-Driven Exposure Pathways Integrated Science Team identifies how ecological pathways and physiological processes within a single organism can alter exposure and toxicity of contaminants and pathogens and seek to understand outcomes at different scales from individuals to populations and ecosystems.
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Ecologically-Driven Exposure Pathways Science Team
July 12, 2021
Ecologically-Driven Exposure Pathways Science Team
The Ecologically-Driven Exposure Pathways Integrated Science Team identifies how ecological pathways and physiological processes within a single organism can alter exposure and toxicity of contaminants and pathogens and seek to understand outcomes at different scales from individuals to populations and ecosystems.
February 17, 2021
Wetland Management Technique Designed to Reduce Mercury in Water and Fish Tested During a Short-Term Field Study
Results from a 3-year study indicate there was support for the use of open- and deep-water treatment pools at the downstream end of seasonal wetlands to reduce methylmercury concentrations in water exported from the wetlands, but the treatment had no measurable effect on wetland fish. Questions remain about the long-term potential for mercury removal using this wetland management strategy.
By
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
Wetland Management Technique Designed to Reduce Mercury in Water and Fish Tested During a Short-Term Field Study
February 17, 2021
Wetland Management Technique Designed to Reduce Mercury in Water and Fish Tested During a Short-Term Field Study
Results from a 3-year study indicate there was support for the use of open- and deep-water treatment pools at the downstream end of seasonal wetlands to reduce methylmercury concentrations in water exported from the wetlands, but the treatment had no measurable effect on wetland fish. Questions remain about the long-term potential for mercury removal using this wetland management strategy.
October 4, 2019
Science to Help Understand Exposure and Toxicological Effects of Environmental Mercury to Representative Birds
Exposure and toxicity of environmental mercury to birds can be enhanced or lessened due to the available sources and forms of mercury and other species dependent factors such as life stage, migratory patterns, foraging and nesting behaviors, transfer of mercury from mothers to eggs, and sex. For example, mercury exposure can lead to sublethal toxicological effects that can influence parental...
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
Science to Help Understand Exposure and Toxicological Effects of Environmental Mercury to Representative Birds
October 4, 2019
Science to Help Understand Exposure and Toxicological Effects of Environmental Mercury to Representative Birds
Exposure and toxicity of environmental mercury to birds can be enhanced or lessened due to the available sources and forms of mercury and other species dependent factors such as life stage, migratory patterns, foraging and nesting behaviors, transfer of mercury from mothers to eggs, and sex. For example, mercury exposure can lead to sublethal toxicological effects that can influence parental...
June 30, 2018
Suisun Marsh Waterfowl and Wildlife Studies
Suisun Marsh provides critical habitat for wintering and breeding waterbirds in California. USGS WERC collaborates with the California Department of Water Resources to examine trends in bird declines and to assess the habitat factors driving long-term survival of waterfowl, rails, and other birds in this important area.
By
Western Ecological Research Center (WERC)
Suisun Marsh Waterfowl and Wildlife Studies
June 30, 2018
Suisun Marsh Waterfowl and Wildlife Studies
Suisun Marsh provides critical habitat for wintering and breeding waterbirds in California. USGS WERC collaborates with the California Department of Water Resources to examine trends in bird declines and to assess the habitat factors driving long-term survival of waterfowl, rails, and other birds in this important area.
June 6, 2018
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
In a study designed to help resource managers when considering mercury exposure risk, scientists determined that sulfur cycling—a process closely related to mercury methylation rates—and ecological conditions that influence exposure are important factors affecting fish mercury concentrations in estuarine wetlands.
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
June 6, 2018
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
In a study designed to help resource managers when considering mercury exposure risk, scientists determined that sulfur cycling—a process closely related to mercury methylation rates—and ecological conditions that influence exposure are important factors affecting fish mercury concentrations in estuarine wetlands.
May 18, 2018
New Method Can Measure Naturally Occurring Element Exposure in Hummingbirds Without Harm
Seventeen naturally occurring trace elements, including those associated with adverse health impacts when birds are exposed to toxic levels (iron, lead, mercury, selenium, zinc, cadmium, and arsenic) were measured in small birds without harm. The nonlethal method was developed for hummingbirds, with Anna's hummingbirds ( Calypte anna) as a test species and can be more broadly applied to other...
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Toxic Substances Hydrology
New Method Can Measure Naturally Occurring Element Exposure in Hummingbirds Without Harm
May 18, 2018
New Method Can Measure Naturally Occurring Element Exposure in Hummingbirds Without Harm
Seventeen naturally occurring trace elements, including those associated with adverse health impacts when birds are exposed to toxic levels (iron, lead, mercury, selenium, zinc, cadmium, and arsenic) were measured in small birds without harm. The nonlethal method was developed for hummingbirds, with Anna's hummingbirds ( Calypte anna) as a test species and can be more broadly applied to other...
October 30, 2017
Waterfowl Ecology in California and the Pacific Flyway
The Suisun Marsh and Central Valley in California offer some of the world’s most important wetland habitats for waterfowl in the Pacific Flyway. Mike Casazza and USGS WERC biologists are providing the science to support and evaluate waterfowl populations and habitat management in North America.
By
Ecosystems Mission Area
Species Management Research Program
Western Ecological Research Center (WERC)
Waterfowl Ecology in California and the Pacific Flyway
October 30, 2017
Waterfowl Ecology in California and the Pacific Flyway
The Suisun Marsh and Central Valley in California offer some of the world’s most important wetland habitats for waterfowl in the Pacific Flyway. Mike Casazza and USGS WERC biologists are providing the science to support and evaluate waterfowl populations and habitat management in North America.
October 30, 2017
Waterbird Breeding Ecology and Management
The San Francisco Bay is designated as a site of hemispheric importance to shorebirds and annually supports over one million waterbirds. Within the USGS WERC waterbird breeding ecology program, Dr. Josh Ackerman and partners are studying habitat selection, movements, and factors influencing waterbird nest success and chick growth and survival.
By
Ecosystems Mission Area
Land Management Research Program
Species Management Research Program
Western Ecological Research Center (WERC)
Waterbird Breeding Ecology and Management
October 30, 2017
Waterbird Breeding Ecology and Management
The San Francisco Bay is designated as a site of hemispheric importance to shorebirds and annually supports over one million waterbirds. Within the USGS WERC waterbird breeding ecology program, Dr. Josh Ackerman and partners are studying habitat selection, movements, and factors influencing waterbird nest success and chick growth and survival.
Filter Total Items: 46
March 5, 2026
American Avocet and Wilson’s Phalarope Locations and Ancillary Data Associated with the U.S. Geological Survey Saline Lake Ecosystems Integrated Water Availability Assessment Program
American Avocet and Wilson’s Phalarope Locations and Ancillary Data Associated with the U.S. Geological Survey Saline Lake Ecosystems Integrated Water Availability Assessment Program
These data describe tracking information and provide location data of American avocets (from 2023-03-18 to 2024-12-31) and Wilson’s phalaropes (from 2023-08-17 to 2023-11-10) collected in support of the U.S. Geological Survey Saline Lakes Ecosystems Integrated Water Availability Assessment Program (USGS SLE IWAA). The data are provided using standardized formats and an attribute...
By
Western Ecological Research Center (WERC)
Saline Lake Ecosystems Integrated Water Availability Assessment
February 27, 2026
Dabbling Duckling Habitat Use and Movements
Dabbling Duckling Habitat Use and Movements
We conducted a multi-year study (2016-2019) to identify elements of wetland habitat management that could potentially benefit breeding ducks. Specifically, we examined the influence of habitat variables in explaining habitat selection of managed wetlands near upland nesting sites by radio-tagged Mallard (Anas platyrhynchos) and Gadwall (Mareca strepera) ducklings in a brackish marsh...
By
Western Ecological Research Center (WERC)
July 15, 2025
Long-term Trends in Spring and Summer-flooded Wetland area in Suisun Marsh, California
Long-term Trends in Spring and Summer-flooded Wetland area in Suisun Marsh, California
We digitized water on the landscape for breeding waterfowl and other wetland-associated species within Suisun Marsh (California, USA) twice each year (spring and summer) during a 38-year period (1984-2021) with remote sensing methods that combined Landsat satellite imagery (composite images) and spectral mixture analysis using Google Earth Engine. This dataset contains the amount of...
By
Western Ecological Research Center (WERC)
July 11, 2025
Nesting Duck Populations in Suisun Marsh, California
Nesting Duck Populations in Suisun Marsh, California
This dataset includes apparent nest density (observed nests per hectare of area searched) of mallard (Anas platyrhynchos) and gadwall (Mareca strepera) in Suisun Marsh, California.
By
Western Ecological Research Center (WERC)
July 11, 2025
Waterbird Nest Abundance in South San Francisco Bay
Waterbird Nest Abundance in South San Francisco Bay
This dataset includes nest abundance of American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), and Forster's terns (Sterna forsteri) in south San Francisco Bay, California by year. It also contains California gull (Larus californicus) hazing research efforts. This dataset was generated from yearly nest monitoring surveys within wetlands in south San...
By
Western Ecological Research Center (WERC)
July 11, 2025
Habitat Features and Waterbird Abundance and Diversity on Managed Wetlands Enrolled in the California Waterfowl Habitat Program
Habitat Features and Waterbird Abundance and Diversity on Managed Wetlands Enrolled in the California Waterfowl Habitat Program
This dataset includes wetland habitat measurements, surrounding land cover metrics, and waterbird abundance and diversity during 240 surveys of 117 individual wetland units enrolled in the California Waterfowl Habitat Program. This dataset was generated from wetland surveys conducted in the Sacramento Valley, San Joaquin Valley, and Suisun Marsh in 2022 and 2023.
By
Western Ecological Research Center (WERC)
October 1, 2024
Waterfowl Brood Drone Surveys from Suisun, California 2019
Waterfowl Brood Drone Surveys from Suisun, California 2019
Effective waterfowl management relies on the collection of relevant demographic data to inform land management decisions; however, some types of data are difficult to obtain. For waterfowl, brood surveys are difficult to conduct because wetland habitats often obscure ducklings from being visually assessed. Here, we used Unoccupied Aerial Systems (UAS) to assess what wetland habitat...
By
Western Ecological Research Center (WERC)
August 15, 2024
Bird use of Winter-Flooded Rice Fields in the Sacramento Valley, California
Bird use of Winter-Flooded Rice Fields in the Sacramento Valley, California
Bird and habitat surveys were conducted in winter-flooded rice fields in the Sacramento Valley, California, USA during the fall and winters of 2021-2022 (Oct 2021 through February 2022) and 2022-2023 (December 2022 through February 2023). Rice field sampling consisted of (1) a bird survey that was followed by (2) an overall habitat assessment and (3) a more detailed habitat transect...
By
Western Ecological Research Center (WERC)
August 12, 2024
Body Mass of Dabbling and Diving Ducks Harvested in California
Body Mass of Dabbling and Diving Ducks Harvested in California
Body mass data (measured in grams) of dabbling and diving ducks harvested in three regions of California: Sacramento Valley, Suisun Marsh, and San Joaquin Valley during the 2014/2015, 2015/2016, 2016/2017, 2018/2019, and 2019/2020 hunting seasons. In addition to mass, the flattened length of right wing, species, sex, age, and date of harvest were also recorded. These data support the...
By
Western Ecological Research Center (WERC)
May 31, 2024
Timing of Occurrence of Waterfowl in U.S. Counties and Canadian Counties, Boroughs, Census Districts, and Other Populated Area Designations with Modeled Exposure Status to Highly Pathogenic Avian Influenza Virus in 2021-2022
Timing of Occurrence of Waterfowl in U.S. Counties and Canadian Counties, Boroughs, Census Districts, and Other Populated Area Designations with Modeled Exposure Status to Highly Pathogenic Avian Influenza Virus in 2021-2022
This data provides county level occurrence information for all individuals used in modelling potential exposure and spread of highly pathogenic avian influenza (HPAIv) from the 2021-2022 North American outbreak. The data set contains individual identifiers and taxa information, an indicator of exposure, exposure status (Susceptible, Exposed by HPAIv detection in the county, or Exposed by...
By
Western Ecological Research Center (WERC)
May 17, 2024
Duckling Survival in a Brackish Marsh
Duckling Survival in a Brackish Marsh
We conducted a multi-year study (2016-2019) to quantify sources of duckling mortality, identify predator type, and estimate survival rates for Mallard (Anas platyrhynchos) and Gadwall (Mareca strepera) ducklings within Suisun Marsh, California.
By
Western Ecological Research Center (WERC)
May 16, 2024
Egg Mercury Concentration and Egg Size in Two Songbird Species
Egg Mercury Concentration and Egg Size in Two Songbird Species
This dataset includes egg total mercury concentrations, egg total mercury burden, egg length, egg width, predicted egg volume, and predicted fresh wet weight according to egg position in the laying sequence for tree swallow and house wren eggs from the Cache Creek Settling Basin and Cosumnes River Preserve, in California's Central Valley during 2018. These data support the following...
By
Western Ecological Research Center (WERC)
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
March 31, 2017
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Scientists from the USGS Western Ecological Research Center (WERC) are conducting a "social attraction" study for seabirds in the Don Edwards San Francisco Bay National Wildlife Refuge. Historically, this region offered wetland habitats to local wildlife. With the introduction of industrial salt ponds and human development, however, much of this habitat was lost.
By
Ecosystems
Wildlife Program
Western Ecological Research Center (WERC)
Communications and Publishing
March 31, 2017
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Establishing Forster's Tern Nesting Colonies
Scientists from the USGS Western Ecological Research Center (WERC) are conducting a "social attraction" study for seabirds in the Don Edwards San Francisco Bay National Wildlife Refuge. Historically, this region offered wetland habitats to local wildlife. With the introduction of industrial salt ponds and human development, however, much of this habitat was lost.
By
Ecosystems
Wildlife Program
Western Ecological Research Center (WERC)
Communications and Publishing
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
May 29, 2010
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph showing white-faced ibis nesting at Bear River Migratory Bird Refuge, Great Salt Lake, Utah. U.S.
By
Contaminant Biology
Toxic Substances Hydrology
Environmental Health Program
May 29, 2010
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph Showing White-Faced Ibis Nesting
Photograph showing white-faced ibis nesting at Bear River Migratory Bird Refuge, Great Salt Lake, Utah. U.S.
By
Contaminant Biology
Toxic Substances Hydrology
Environmental Health Program
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
June 3, 2004
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Photo of Foster's Tern (Sterna forsteri) while hunting. Forster’s terns are among the most at-risk wildlife species to mercury toxicity in western North America.
By
Contaminant Biology
Toxic Substances Hydrology
Environmental Health Program
June 3, 2004
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Foster's Tern (Sterna forsteri) While Hunting in Flight
Photo of Foster's Tern (Sterna forsteri) while hunting. Forster’s terns are among the most at-risk wildlife species to mercury toxicity in western North America.
By
Contaminant Biology
Toxic Substances Hydrology
Environmental Health Program
December 23, 2019
Synthesis of maternal transfer of mercury in birds: Implications for altered toxicity risk
Synthesis of maternal transfer of mercury in birds: Implications for altered toxicity risk
Maternal transfer is the predominant route of methylmercury (MeHg) exposure to offspring. We reviewed and synthesized published and unpublished data on maternal transfer of MeHg in birds. Using paired samples of females’ blood (n=564) and their eggs (n=1814) from 26 bird species in 6 taxonomic orders, we conducted a meta-analysis to evaluate whether maternal transfer of MeHg to eggs...
Authors
Joshua T. Ackerman, Mark P. Herzog, David C. Evers, Daniel A. Cristol, Kevin P. Kenow, Gary Heinz, Raphael A Lavoie, Rebecka Brasso, Mark L. Mallory, Jennifer F Provencher, Birgit M Braune, Angela Matz, Joel A. Schmutz, Collin A. Eagles-Smith, Lucas J Savoy, Michael W. Meyer, C. Alex Hartman
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
Filter Total Items: 206
March 5, 2026
Monitoring nesting waterbirds for the South Bay Salt Pond Restoration Project—2024 breeding season
Monitoring nesting waterbirds for the South Bay Salt Pond Restoration Project—2024 breeding season
The San Francisco Bay supports thousands of breeding waterbirds annually and hosts large populations of American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), and Forster’s terns (Sterna forsteri). These three species have relied largely on former commercial salt ponds in south San Francisco Bay, which provide wetland foraging habitat and island nesting...
Authors
Joshua T. Ackerman, C. Alex Hartman, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
January 23, 2026
Waterfowl move less in heterogeneous and human-populated landscapes, with implications for spread of avian influenza viruses
Waterfowl move less in heterogeneous and human-populated landscapes, with implications for spread of avian influenza viruses
Animal movements contribute to the spread of infectious diseases and are driven in part by environmental conditions. We investigated the links among the environment, animal movement, and infectious disease dynamics in waterfowl, which are among the primary wildlife hosts of avian influenza viruses. By combining telemetry data on 4606 individuals from 26 waterfowl species with data on...
Authors
Claire Stewart Teitelbaum, Diann J. Prosser, Joshua T. Ackerman, Sakib Ahmed, A.B.M. Sarowar Alam, Kazi Zenifar Azmiri, Nyambaya Batbayar, Joël Bêty, Abigail Blake-Bradshaw, Dmitrijs Boiko, Nelleke H. Buitendijk, Jeffrey J. Buler, David Cabot, Michael L. Casazza, Bradley S. Cohen, Batmunkh Davaasuren, Sébastien Farau, Jamie Feddersen, John R. Fieberg, Wolfgang Fiedler, Peter Glazov, Larry R. Griffin, Matthieu Guillemain, Heath Hagy, Matthew J. Hardy, Cory Highway, David Hoffman, Tehan Kang, Allison Keever, Jennifer Kilburn, Andrea Kölzsch, Helmut Kruckenberg, Toni Laaksonen, Brian S. Ladman, Hansoo Lee, Siwan Lee, Josée Lefebvre, Pierre Legagneux, Hans Linssen, Jesper Madsen, Nicholas M. Masto, Scott R. McWilliams, Tori Mezebish Quinn, Carl P.J. Mitchell, Axelle Moreau, Gerhard Müskens, Scott Newman, Bart A. Nolet, Rascha J.M. Nuijten, Jay Osenkowski, Cory T. Overton, Antti Piironen, Betty Plaquin, Andrew M. Ramey, Jean Rodrigue, David Rodrigues, Kees H.T. Schreven, Yali Si, Jeffery D. Sullivan, John Takekawa, Philippe J. Thomas, Mariëlle van Toor, Jonas Waldenström, Christopher K. Williams, David W. Wolfson, Fei Xu, Ian G. Brosnan, Susan E.W. De La Cruz
By
Cooperative Research Units
September 18, 2025
Habitat features influencing waterbird use of managed wetlands enrolled in a public-private partnership for land conservation: The California Waterfowl Habitat Program
Habitat features influencing waterbird use of managed wetlands enrolled in a public-private partnership for land conservation: The California Waterfowl Habitat Program
Draining, water diversion, and development have greatly reduced the availability of freshwater wetland habitat around the world, and many remaining wetlands are on private lands. Public–private partnership programs can be an important means for promoting habitat conservation and management on private lands. We investigated bird use of 117 wetlands enrolled in the California Waterfowl...
Authors
C. Alex Hartman, Joshua T. Ackerman, Sarah H. Peterson, Brady Lynn Fettig, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
November 20, 2024
Surveying waterfowl broods in wetlands using aerial drones
Surveying waterfowl broods in wetlands using aerial drones
Effective waterfowl management relies on the collection of relevant demographic data to inform land management decisions; however, some types of data are difficult to obtain. For waterfowl, brood surveys are difficult to conduct because wetland habitats often obscure ducklings from being visually assessed. Here, we used Unoccupied Aerial Systems (UAS) to assess what wetland habitat...
Authors
Desmond Alexander Mackell, Michael L. Casazza, Cory T. Overton, Kevin J. Buffington, Chase M. Freeman, Joshua T. Ackerman, Karen M. Thorne
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
November 20, 2024
Bird habitat value and management priorities of the California Winter Rice Habitat Incentive Program
Bird habitat value and management priorities of the California Winter Rice Habitat Incentive Program
Flooding rice (Oryza sativa) agricultural fields during winter to facilitate rice straw decomposition has mitigated the loss of some of the natural wetlands in California’s Central Valley. We conducted bird surveys in 253 rice checks (2,158 ha) within 177 rice fields in the Sacramento Valley during the fall and winter of 2021-2022 and 2022-2023 to evaluate factors influencing bird use of...
Authors
Sarah H. Peterson, Joshua T. Ackerman, Carley R. Schacter, C. Alex Hartman, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
August 12, 2024
Body mass changes of dabbling and diving ducks wintering in California
Body mass changes of dabbling and diving ducks wintering in California
Bird body mass is often used as an index of body condition and fluctuates throughout the year in response to environmental conditions and avian life-history events. We examined the body mass of 59,572 ducks representing 13 species (7 dabbling duck species and 6 diving duck species) harvested within the 3 regions of the Central Valley in California, USA (Sacramento Valley, Suisun Marsh...
Authors
Mark P. Herzog, Joshua T. Ackerman, Jeffrey D. Kohl, Brady Lynn Fettig, C. Alex Hartman, Sarah H. Peterson, Michael L. Casazza, Joseph P. Fleskes
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
July 18, 2024
Mitigating risk: Predicting H5N1 avian influenza spread with an empirical model of bird movement
Mitigating risk: Predicting H5N1 avian influenza spread with an empirical model of bird movement
Understanding timing and distribution of virus spread is critical to global commercial and wildlife biosecurity management. A highly pathogenic avian influenza virus (HPAIv) global panzootic, affecting ~600 bird and mammal species globally and over 83 million birds across North America (Dec 2023), poses a serious global threat to animals and public health. We combined a large, long-term...
Authors
Fiona McDuie, Cory T. Overton, Austen Lorenz, Elliott Matchett, Andrea Mott, Desmond Alexander Mackell, Joshua T. Ackerman, Susan E.W. De La Cruz, Vijay P. Patil, Diann Prosser, John Y. Takekawa, Dennis L. Orthmeyer, Maurice E. Pitesky, Samuel L. Diaz-Munoz, Brock M. Riggs, Joseph Gendreau, Eric T. Reed, Mark J. Petrie, Chris K. Williams, Jeffrey J. Buler, Matthew J. Hardy, Brian S. Ladman, Pierre Legagneux, Joel Bety, Philippe J. Thomas, Jean Rodrigue, Josee Lefebvre, Michael L. Casazza
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
June 10, 2024
Egg mercury concentration and egg size varies with position in the laying sequence in two songbird species
Egg mercury concentration and egg size varies with position in the laying sequence in two songbird species
In birds, mercury embryotoxicity can occur through the transfer of mercury from the female to her eggs. Maternal transfer of mercury can vary by egg position in the laying sequence, with first-laid eggs often exhibiting greater mercury concentrations than subsequently laid eggs. We studied egg mercury concentration, mercury burden (total amount of mercury in the egg), and egg...
Authors
C. Alex Hartman, Joshua T. Ackerman, Breanne Cooney, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
May 13, 2024
Duckling survival increased with availability of flooded wetland habitat and decreased with salinity concentrations in a brackish marsh
Duckling survival increased with availability of flooded wetland habitat and decreased with salinity concentrations in a brackish marsh
Waterfowl population recruitment is sensitive to duckling survival. We quantified predator types and survival rates for Anas platyrhynchos (Mallard) and Mareca strepera (Gadwall) ducklings in one of the largest brackish water marshes in western North America (Suisun Marsh, California) using 556 radio-tagged ducklings from 284 broods tracked during the 2016 to 2019 breeding seasons...
Authors
Sarah H. Peterson, Joshua T. Ackerman, C. Alex Hartman, Andrew C. Greenawalt, Michael L. Casazza, Mark P. Herzog
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
April 29, 2024
Global mercury concentrations in biota: Their use as a basis for a global biomonitoring framework
Global mercury concentrations in biota: Their use as a basis for a global biomonitoring framework
An important provision of the Minamata Convention on Mercury is to monitor and evaluate the effectiveness of the adopted measures and its implementation. Here, we describe for the first time currently available biotic mercury (Hg) data on a global scale to improve the understanding of global efforts to reduce the impact of Hg pollution on people and the environment. Data from the peer...
Authors
David C. Evers, Joshua T. Ackerman, Staffan Akerblom, Dominique Bally, Niladri Basu, Kevin Bishop, Nathalie Bodin, Hans Fredrik Veitberg Braaten, Mark Burton, Paco Bustamante, Celia Y. Chen, John Chetelat, Linroy Christian, Rune Dietz, Paul Drevnick, Collin A. Eagles-Smith, Luis Fernandez, Neil Hammerschlag, Mireille Harmelin-Vivien, Agustin Harte, Eva Kruemmel, Jose Lailson-Brito, Gabriella Medina, Cesar Rodriguez, Iain Stenhouse, Elsie M. Sunderland, Akinori Takeuchi, Timothy Tear, Claudia Vega, Simon Wilson, Pianpian Wu
By
Ecosystems Mission Area
Contaminant Biology
Environmental Health Program
Forest and Rangeland Ecosystem Science Center
Western Ecological Research Center (WERC)
April 29, 2024
Methylmercury effects on birds: A review, meta-analysis, and development of toxicity reference values for injury assessment based on tissue residues and diet
Methylmercury effects on birds: A review, meta-analysis, and development of toxicity reference values for injury assessment based on tissue residues and diet
Birds are used as bioindicators of environmental mercury (Hg) contamination, and toxicity reference values are needed for injury assessments. We conducted a comprehensive review, summarized data from 168 studies, performed a series of Bayesian hierarchical meta-analyses, and developed new toxicity reference values for the effects of methylmercury (MeHg) on birds using a benchmark dose...
Authors
Joshua T. Ackerman, Sarah H. Peterson, Mark P. Herzog, Julie L. Yee
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
April 24, 2024
Eggshell membrane thickness and its contribution to total eggshell thickness for 13 waterbird species
Eggshell membrane thickness and its contribution to total eggshell thickness for 13 waterbird species
Eggshell thickness can be an indicator of environmental pollution in wild birds and shell quality in wild and domestic birds, but it is difficult to measure calcite eggshell thickness due to the presence of the adherent outer eggshell membrane. Eggshells of 13 waterbird species were divided in half longitudinally and the outer membrane was removed from one of the halves. Subsequently, we...
Authors
Gary M. Santolo, Sarah H. Peterson, Breanne Cooney, C. Alex Hartman, Mark P. Herzog, Joshua T. Ackerman
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
February 26, 2021
Waterfowl Ecology in Suisun Marsh and the Pacific Flyway
Waterfowl Ecology in Suisun Marsh and the Pacific Flyway
Learn about waterfowl research by scientists at the USGS Western Ecological Research Center.
By
Ecosystems Mission Area
Western Ecological Research Center (WERC)
San Francisco Bay and Sacramento-San Joaquin Delta Estuary
April 29, 2024
Methylmercury Effects on Birds: Percent Injury Tool
Methylmercury Effects on Birds: Percent Injury Tool
Welcome to The Bird Mercury Tool website. Please follow the guidance below to download the tool and user guide. The Bird Mercury Tool: Estimating Methylmercury Injury to Birds can be used by practitioners to help interpret injury to birds caused by methylmercury concentrations in bird tissues or diet. The dataset, statistical models, and assumptions used within this tool have been...
By
Western Ecological Research Center (WERC)
Filter Total Items: 21
Helping the California Winter Rice Habitat Incentive Program increase bird use of winter-flooded rice fields
December 29, 2025
Helping the California Winter Rice Habitat Incentive Program increase bird use of winter-flooded rice fields
The Central Valley of California provides important habitat for waterbirds (waterfowl, shorebirds, and wading birds).
Read Article
Duckling survival is higher if nests are closer to wetland habitats flooded during the summer
December 29, 2025
Duckling survival is higher if nests are closer to wetland habitats flooded during the summer
A recent USGS study, in collaboration with the California Department of Fish and Wildlife at the Grizzly Island Wildlife Area, investigates what type...
Read Article
RESEARCH SPOTLIGHT: Understanding Mercury’s Effects on Birds
June 10, 2024
RESEARCH SPOTLIGHT: Understanding Mercury’s Effects on Birds
In a recent study published in Environmental Toxicology and Chemistry, USGS researchers have derived new mercury toxicity reference values and...
Read Article
Re-establishing Waterbird Breeding Colonies in San Francisco Bay
April 17, 2024
Re-establishing Waterbird Breeding Colonies in San Francisco Bay
Learn more about how our partners are using ​science and management to maintain and establish new ​bird ​nesting colonies in support of the South Bay...
Read Article
Research Spotlight: What Habitat Features Make Duck Nests Vulnerable to Raccoons and Striped Skunks?
April 20, 2023
Research Spotlight: What Habitat Features Make Duck Nests Vulnerable to Raccoons and Striped Skunks?
Research by USGS scientists finds that predator-specific behaviors can shape where duck nests are most vulnerable in Suisun Marsh, CA. The findings...
Read Article
Research Spotlight: High Salinity and Limited Wetlands Reduce Duckling Habitat for Waterfowl
October 5, 2021
Research Spotlight: High Salinity and Limited Wetlands Reduce Duckling Habitat for Waterfowl
A new publication by USGS scientists examines wetland availability and salinity in Suisun Marsh, with particular focus on the implications for young...
Read Article
Research Spotlight: New Study Explores Nocturnal Nest Breaks and Predation Events for Dabbling Ducks
August 18, 2021
Research Spotlight: New Study Explores Nocturnal Nest Breaks and Predation Events for Dabbling Ducks
A new study by USGS scientists, in collaboration with the California Department of Water Resources and California Department of Fish and Wildlife...
Read Article
Isotope Fractionation from In Vivo Methylmercury Detoxification in Waterbirds
July 16, 2021
Isotope Fractionation from In Vivo Methylmercury Detoxification in Waterbirds
Animals that are higher on the trophic chain, such as waterbirds that primarily rely on fish, are at risk for ingesting methylmercury in their diet...
Read Article
Research Spotlight: Precise Eggshell Thickness Measurements To Inform Bird Ecology And Mercury Monitoring
February 10, 2021
Research Spotlight: Precise Eggshell Thickness Measurements To Inform Bird Ecology And Mercury Monitoring
In a study published in the journal Ecology and Evolution, USGS biologists provide precise eggshell thickness measurements for 12 species of birds...
Read Article
Research Spotlight: Wetland Habitats and Aquatic Prey May Drive High Hair Mercury Concentrations in Suisun Marsh Raccoons
February 3, 2021
Research Spotlight: Wetland Habitats and Aquatic Prey May Drive High Hair Mercury Concentrations in Suisun Marsh Raccoons
A new study by scientists from USGS in collaboration with the California Department of Water Resources has found that mercury concentrations detected...
Read Article
Research Spotlight: Mercury Exposure in Wild Songbirds Associated with Disrupted Parental Care at the Nest
June 30, 2019
Research Spotlight: Mercury Exposure in Wild Songbirds Associated with Disrupted Parental Care at the Nest
In a study published in the journal Environmental Science and Technology, U.S. Geological Survey biologists report that methylmercury concentrations...
Read Article
Research Spotlight: Ducklings Leave Nests in Early Morning, Suggesting Predator Avoidance
June 12, 2019
Research Spotlight: Ducklings Leave Nests in Early Morning, Suggesting Predator Avoidance
In a study published in the journal Ecology and Evolution, U.S. Geological Survey (USGS) biologists put small cameras next to duck nests to determine...
Read Article
Was this page helpful?