The Ecologically-Driven Exposure pathways team identifies internal and external pathways and processes that can alter exposure and toxicity of contaminants and pathogens to wildlife the environment. That information is used to distinguish actual health risks to fish and wildlife. If actual risks are identified this project will inform how to economically and effectively minimize risk by providing scientific data and understandings about the management practice as well as related environmental transport, fate, and exposure pathways of contaminants and pathogens. Emphasis will be placed on addressing these issues on public and Department of the Interior managed landscapes.
Contaminant and pathogen exposure alone does not necessarily result in adverse health outcomes in fish, wildlife, or humans. There are numerous pathways and processes that can alter the toxicity of naturally occurring and human-made contaminants in the environment.
The team uses their broad scientific expertise in hydrology, geochemistry, biology, and ecotoxicoogy to understand the complexities associated with the movement of toxicants and pathogens through the environment and within individual organisms. That information is used to determine how, where, and when exposure occurrs and if exposure results in health risks to wildlife and humans.
Current Science Questions and Activities
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What are the various ecological factors, such as habitats and foraging strategies, that influence the pathways of contaminant exposure, health risks to fish and wildlife?
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What are the major intrinsic and extrinsic drivers of mercury exposure and risk to humans, fish, and wildlife at a global scale?
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What are the internal physiological determinants such as metababolism, transfer of mercury to offspring, changes in body mass, and molting that influence exposure and health risks in fish and wildlife?
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How do the internal factors differ among species and life stages?
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What are the Influences of landscape alterations, perturbations, and restoration on pathways and movement of contaminants through ecosystems and bioaccumulation into the food web of aquatic biota?
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Do multiple types and chemical mixtures have additive, synergistic, or antagonistic effects that influence the health of fish and wildlife?
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What are the internal and external drivers and regulators of human exposure to mercury?
- What is the risk of pathogen exposure and transmission among wildlife, livestock, and humans?
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What are the key environmental factors that control the viability of avian influenza virus shed by wild birds and what are the key environmental pathways of exposure and transmission of the virus?
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What is the role of soil, water, and vegetation in disease transmission such as Chronic Wasting Disease?
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How do invasive species influence the timing of contaminant uptake and bioaccumulation in fish and wildlife?
USGS science related to this science team’s activities.
Food Web Changes Dampen Expected Reductions in Lake Trout Mercury Levels in Lake Michigan—Invasive Species Play Major Role
Mercury Isotope Ratios used to Determine Sources of Mercury to Fish in Northeast U.S. Streams
Science to Help Understand Exposure and Toxicological Effects of Environmental Mercury to Representative Birds
No Adverse Reproductive Effects Observed in Tree Swallows Exposed to Perfluoroalkyl Substances in Clarks Marsh, Michigan
Roadmap to Understanding Factors Influencing Mercury Exposure and Adverse Health Effects
Systematic Approach to Understanding Tree Swallow Health in the Great Lakes Region—Science to Inform Restoration
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
Simple Ways to Avoid Public Exposures to Infectious Wildlife Diseases Summarized
New Method Can Measure Naturally Occurring Element Exposure in Hummingbirds Without Harm
Body Symmetry in Forster's Terns Related to Mercury Exposure
Efficacy of Eggshell Analyses as a Nonlethal Method to Estimate Mercury Exposure in Bird Embryos
New Method Improves Measurement of Bullet Fragments in Culled Varmints
- Overview
The Ecologically-Driven Exposure pathways team identifies internal and external pathways and processes that can alter exposure and toxicity of contaminants and pathogens to wildlife the environment. That information is used to distinguish actual health risks to fish and wildlife. If actual risks are identified this project will inform how to economically and effectively minimize risk by providing scientific data and understandings about the management practice as well as related environmental transport, fate, and exposure pathways of contaminants and pathogens. Emphasis will be placed on addressing these issues on public and Department of the Interior managed landscapes.
Sources/Usage: Public Domain.Photograph showing white-faced ibis nesting at Bear River Migratory Bird Refuge, Great Salt Lake, Utah. U.S. Geological Survey (USGS) scientists evaluated a nonlethal method to estimate mercury in the embryos of 23 bird species using mercury content in eggshells. This method was effective for a wide range of ages and species.(Credit: Josh T. Ackerman, Western Ecological Research Center. Public domain.) Contaminant and pathogen exposure alone does not necessarily result in adverse health outcomes in fish, wildlife, or humans. There are numerous pathways and processes that can alter the toxicity of naturally occurring and human-made contaminants in the environment.
The team uses their broad scientific expertise in hydrology, geochemistry, biology, and ecotoxicoogy to understand the complexities associated with the movement of toxicants and pathogens through the environment and within individual organisms. That information is used to determine how, where, and when exposure occurrs and if exposure results in health risks to wildlife and humans.
Current Science Questions and Activities
-
What are the various ecological factors, such as habitats and foraging strategies, that influence the pathways of contaminant exposure, health risks to fish and wildlife?
-
What are the major intrinsic and extrinsic drivers of mercury exposure and risk to humans, fish, and wildlife at a global scale?
-
What are the internal physiological determinants such as metababolism, transfer of mercury to offspring, changes in body mass, and molting that influence exposure and health risks in fish and wildlife?
-
How do the internal factors differ among species and life stages?
-
What are the Influences of landscape alterations, perturbations, and restoration on pathways and movement of contaminants through ecosystems and bioaccumulation into the food web of aquatic biota?
-
Do multiple types and chemical mixtures have additive, synergistic, or antagonistic effects that influence the health of fish and wildlife?
-
What are the internal and external drivers and regulators of human exposure to mercury?
- What is the risk of pathogen exposure and transmission among wildlife, livestock, and humans?
-
What are the key environmental factors that control the viability of avian influenza virus shed by wild birds and what are the key environmental pathways of exposure and transmission of the virus?
-
What is the role of soil, water, and vegetation in disease transmission such as Chronic Wasting Disease?
-
How do invasive species influence the timing of contaminant uptake and bioaccumulation in fish and wildlife?
-
- Science
USGS science related to this science team’s activities.
Filter Total Items: 21Food Web Changes Dampen Expected Reductions in Lake Trout Mercury Levels in Lake Michigan—Invasive Species Play Major Role
Combined analyses of mercury, nitrogen, and carbon isotopes in archived lake trout (Salvelinus namaycush) tissues and sediment cores in Lake Michigan from 1978 to 2012 indicated that lake trout mercury concentrations mirrored declines in mercury sources prior to the arrival of invasive species that changed mercury transfer through the food and dampened the expected decreases in mercury...Mercury Isotope Ratios used to Determine Sources of Mercury to Fish in Northeast U.S. Streams
Mercury isotope analyses were used to distinguish different sources of mercury to fish in 23 streams along a forested-rural to urban-industrial land-use gradient in the Northeastern United States. The use of mercury isotope measurements in fish tissue allow for distinguishing different sources of mercury that are bioaccumulating into the food web. Mercury isotope signatures in fish in forested...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...No Adverse Reproductive Effects Observed in Tree Swallows Exposed to Perfluoroalkyl Substances in Clarks Marsh, Michigan
Perfluoroalkyl substance (PFAS) concentrations in tree swallows (Tachycineta bicolor) breeding at Clarks Marsh near a decommissioned U.S. Air Force base in Michigan were among the highest concentrations ever documented in birds indicating significant PFAS exposures. In contrast to previous studies where reproductive impairment was documented at lower PFAS exposure, there were no adverse effects on...Roadmap to Understanding Factors Influencing Mercury Exposure and Adverse Health Effects
In a comprehensive overview, scientists explain that human and wildlife exposure and toxicological responses to mercury are dependent on factors that operate across global, individual, and molecular scales. They provide a roadmap for unified research to facilitate a better understanding of human and wildlife health risks from mercury exposure.Systematic Approach to Understanding Tree Swallow Health in the Great Lakes Region—Science to Inform Restoration
Four papers by U.S. Geological Survey (USGS) scientists document tree swallow (Tachycineta bicolor) chemical exposure, physiological responses, and reproductive success in the Great Lakes region. These studies were designed to understand if there are health threats to swallows from contaminant exposure, and to provide resource managers with information about the actual as opposed to the perceived...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.Simple Ways to Avoid Public Exposures to Infectious Wildlife Diseases Summarized
The U.S. Geological Survey (USGS), in collaboration with the U.S. Fish and Wildlife Service (USFWS) and other disease specialists, have published reports during the past 12 years with information about the geographic distribution of diseases, specific pathogens, disease ecology, and strategies to avoid human exposure and infection for seven zoonotic diseases.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...Body Symmetry in Forster's Terns Related to Mercury Exposure
Body symmetry of Forster's terns (Sterna forsteri) in San Francisco Bay was related to blood and feather mercury concentrations. Body asymmetry can affect a bird's fitness by reducing flight efficiency, thus increasing energetic costs (especially during migration) and interrupting normal feeding and breeding behaviors.Efficacy of Eggshell Analyses as a Nonlethal Method to Estimate Mercury Exposure in Bird Embryos
U.S. Geological Survey (USGS) scientists evaluated a nonlethal method to estimate mercury in the embryos of 23 bird species using mercury content in eggshells. This method was effective for a wide range of ages and species.New Method Improves Measurement of Bullet Fragments in Culled Varmints
A creative combination of radiography and techniques borrowed from meat processing and gold prospecting led to a better method for determining the lead content in ground squirrels shot by hunters to evaluate potential exposure risk to avian scavengers such as golden eagles (Aquila chrysaetos). - Data
- Publications