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.
His 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.
Education
- Ph.D. 2002, Ecology, University of California-Davis
- B.S. 1997 (Magna Cum Laude), Wildlife, Fish, and Conservation Biology, University of California-Davis
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
Selected Publications
2020 Ackerman, JT, MP Herzog, DC Evers, DA Cristol, KP Kenow, GH Heinz, RA Lavoie, RL Brasso, ML Mallory, JF Provencher, BM Braune, A Matz, JA Schmutz, CA Eagles-Smith, LJ Savoy, MW Meyer, and CA Hartman. Synthesis of maternal transfer of mercury in birds: implications for altered toxicity risk. Environmental Science and Technology 54:2878-2891.
2016 Ackerman, JT, CA Eagles-Smith, MP Herzog, CA Hartman, SH Peterson, DC Evers, AK Jackson, JE Elliott, SS Vander Pol, and CE Bryan. Avian mercury exposure and toxicological risk across western North America: a synthesis. Science of the Total Environment 568:749-769.
2014 Ackerman, JT, MP Herzog, GS Yarris, ML Casazza, E Burns, and JM Eadie. Chapter 5: Waterfowl ecology and management in Suisun Marsh: Ecological History and Possible Futures. University of California Press: Berkeley, California.
Science and Products
Avian Influenza Prevalence Correlated to Mercury Concentrations in Wild Waterfowl
Ecologically-Driven Exposure Pathways Science Team
Wetland Management Technique Designed to Reduce Mercury in Water and Fish Tested During a Short-Term Field Study
Science to Help Understand Exposure and Toxicological Effects of Environmental Mercury to Representative Birds
Suisun Marsh Waterfowl and Wildlife Studies
Scientists Identify Processes that Affect Fish Mercury Concentrations in Estuarine Wetlands
New Method Can Measure Naturally Occurring Element Exposure in Hummingbirds Without Harm
Waterbird Breeding Ecology and Management
Mercury Bioaccumulation in Wetlands
Breeding and Wintering Ecology of Waterfowl
Contaminants in Waterbirds and Effects on Avian Reproduction
Efficacy of Eggshell Analyses as a Nonlethal Method to Estimate Mercury Exposure in Bird Embryos
Predator Movements and Duck Nests in Relation to Habitat Features in Suisun Marsh, CA (2016-2019)
Data describing infection status and movement ecology of North American waterfowl
Data measuring avian influenza infection, mercury concentration, and body condition in wild waterfowl
Nocturnal Incubation Recess and Flushing Behavior by Duck Hens Nesting in Grizzly Island Wildlife Area 2015-2018
Migration stopover ecology of cinnamon teal in western North America
Egg Morphometric Data Obtained for White-faced Ibis Nesting in Bear River Migratory Bird Refuge, Great Salt Lake, Utah (2010-2012)
How Mallard and Gadwall Hens Nesting in Grizzly Island Wildlife Area Respond when Flushed (2015 - 2018)
Breeding Waterbird Populations in South San Francisco Bay 2005-2019
Mercury Concentrations in Western Gulls along the West Coast, USA, 2015-2017
Hair and blood total mercury concentrations in raccoons and striped skunks from Suisun Marsh 2016 to 2019
Avian Eggshell Thickness for 12 Species in the Western U.S. from 2014 to 2018
Mercury Bioaccumulation in US National Parks Using Dragonfly Larvae as Biosentinels, 2009-2018
South San Francisco Bay Salt Pond Restoration Project—A synthesis of Phase-1 mercury studies
Waterfowl recently infected with low pathogenic avian influenza exhibit reduced local movement and delayed migration
Dabbling duck eggs hatch after nest abandonment in the wild
Postbreeding movements and molting ecology of female gadwalls and mallards
Predator movements in relation to habitat features reveal vulnerability of duck nests to predation
Avian influenza antibody prevalence increases with mercury contamination in wild waterfowl
Spatiotemporal changes in influenza A virus prevalence among wild waterfowl inhabiting the continental United States throughout the annual cycle
Mercury contamination and potential health risks to Arctic seabirds and shorebirds
Machine learned daily life history classification using low frequency tracking data and automated modelling pipelines: Application to North American waterfowl
Quantitative meta-analysis reveals no association between mercury contamination and body condition in birds
Pathways for avian influenza virus spread: GPS reveals wild waterfowl in commercial livestock facilities and connectivity with the natural wetland landscape
Host correlates of avian influenza virus infection in wild waterfowl of the Sacramento Valley, California
Re-establishing Waterbird Breeding Colonies in San Francisco Bay
This U.S. Geological Survey (USGS), Western Ecological Research Center (WERC) story map details how partners are using science and management to maintain and establish new bird nesting colonies in support of the South Bay Salt Pond Restoration Project. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Science and Products
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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.Ecologically-Driven Exposure Pathways Science Team
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...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.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...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.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.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...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.Mercury Bioaccumulation in Wetlands
Wetlands provide numerous ecosystem services, but also can be sources of methylmercury production and export. Click the next tab to learn how WERC's Dr. Josh Ackerman is evaluating the ecological factors that drive contaminant bioaccumulation in wetland-dependent fish and wildlife.Breeding and Wintering Ecology of Waterfowl
Western U.S. wetlands provide critical habitat for wintering and breeding waterfowl in California. WERC's Dr. Josh Ackerman is working toward collecting data to understand factors influencing duck nest success, to improve and restore breeding habitat for resident duck populations in California, and understand composition of predator communities. To learn more about how USGS WERC is implementing...Contaminants in Waterbirds and Effects on Avian Reproduction
California’s Central Valley and San Francisco Bay Estuary have a long history of mercury contamination from past mercury mining and gold extraction. Waterbirds are particularly susceptible to mercury because of their use of wetland habitats where methylmercury (the most toxic and biologically available form) is produced and relatively low methylmercury exposure can reduce reproductive success...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. - Data
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Predator Movements and Duck Nests in Relation to Habitat Features in Suisun Marsh, CA (2016-2019)
This dataset describes mesopredator locations (raccoons and striped skunks), dabbling duck nest locations (mallard, gadwall, and cinnamon teal), northern harrier nest locations, and random locations in relation to a set of habitat features in Suisun Marsh, California during 2016 through 2019. We designed a series of questions to link fine-scale predator movements and vulnerability of dabbling duckData describing infection status and movement ecology of North American waterfowl
These data, which support a USGS authored manuscript, describe how active and previous previous infection with avian influenza impacts the movement ecology of several wild waterfowl species that overwinter in California. Results varied by species and demonstrate that the relationships between avian influenza infection and wild bird movements are context- and species-dependent.Data measuring avian influenza infection, mercury concentration, and body condition in wild waterfowl
These data represent mercury contamination, influenza infection, and body condition in 11 species of dabbling and diving ducks in the Pacific Flyway. These data support a USGS lead scientific publication.Nocturnal Incubation Recess and Flushing Behavior by Duck Hens Nesting in Grizzly Island Wildlife Area 2015-2018
This dataset describes nocturnal incubation recess behavior for mallard and gadwall hens nesting in Grizzly Island Wildlife Area in breeding seasons 2015-2018. It includes the frequency, start time and duration of recesses, and details a method for determining whether a recess was initiated in response to a predator at the nest using nest temperature data. These data support the following pubMigration stopover ecology of cinnamon teal in western North America
Identifying migration routes and fall stopover sites of cinnamon teal (Spatula cyanoptera septentrionalium) can provide a spatial guide to management and conservation efforts, and address vulnerabilities in wetland networks that support migratory waterbirds. Using high spatio-temporal resolution GSM-GPS transmitters, we tracked the fall migration of 61 cinnamon teal across western North America ovEgg Morphometric Data Obtained for White-faced Ibis Nesting in Bear River Migratory Bird Refuge, Great Salt Lake, Utah (2010-2012)
This data consists of egg morphometric data from white-faced ibis. Eggs were collected in the field and then measured and dissected in the lab to obtain estimates of length, width and mass. This data supports the following publication: Herzog, M.P., Ackerman, J.T. and Hartman, C.A., 2021. Egg morphometrics and egg shape coefficients for White-faced Ibis (Plegadis chihi). The Wilson JournalHow Mallard and Gadwall Hens Nesting in Grizzly Island Wildlife Area Respond when Flushed (2015 - 2018)
This dataset describes responses to flushes by surveyors and predators for mallard and gadwall hens nesting on the Grizzly Island Wildlife Area, Suisun Marsh, California in 2015 through 2018. It includes the start time and duration of recesses, as well as the cause of recess initiation and responses of hens to various trapping activities at the nest site. These data support the following publBreeding Waterbird Populations in South San Francisco Bay 2005-2019
The dataset includes three separate excel spreadsheets which provides waterbird (and predator) observations within individual survey units during the May 2019 breeding waterbird survey of south San Francisco Bay (2019WaterbirdSurveyFullData.xlsx), the total number of American avocets, black-necked stilts, and Forster's terns within each pond unit surveyed during the May 2019 survey (2019WaterbirdSMercury Concentrations in Western Gulls along the West Coast, USA, 2015-2017
We investigated whether foraging habitat, sex, or fidelity to a foraging area effected blood mercury concentrations in western gulls (Larus occidentalis) from three colonies on the west coast of the United States. Dataset includes total mercury concentrations in western gulls from three colony locations and associated foraging habitat of individual gulls. These data support the following publicHair and blood total mercury concentrations in raccoons and striped skunks from Suisun Marsh 2016 to 2019
Total mercury concentrations were determined in hair and whole blood of raccoons and skunks in Suisun Marsh from 2016 to 2019. Individual skunks and raccoons were identified by a unique identifier (Animal_ID) and some animals were sampled multiple times. This dataset includes animal sex, age class, the date the sample was collected, animal body mass, head length, and head-to-torso length. TheAvian Eggshell Thickness for 12 Species in the Western U.S. from 2014 to 2018
Eggshell thickness was measured at the egg equator and poles (sharp pole and blunt pole) for 12 avian species. Eggshell thickness was related to egg morphometrics (egg length and width), embryonic development, egg status, and mercury contamination. Individual eggshells each have up to 3 thickness measurements, linked by the eggshell identification. Each measurement has the corresponding egg lengthMercury Bioaccumulation in US National Parks Using Dragonfly Larvae as Biosentinels, 2009-2018
Comma-separated values (.csv) files containing data related to a National-scale assessment of mercury bioaccumulation in the US National Parks using dragonfly larvae as biosentinels through a citizen science framework. - Multimedia
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South San Francisco Bay Salt Pond Restoration Project—A synthesis of Phase-1 mercury studies
The South Bay Salt Pond Restoration Project (SBSPRP) encompasses over 6,000 hectares of former salt production ponds along the south edge of the San Francisco Bay and represents the largest wetland restoration effort on the west coast of North America. A series of studies associated with Phase 1 (2010–2018) restoration activities that are focused on a historically mercury contaminated slough and sWaterfowl recently infected with low pathogenic avian influenza exhibit reduced local movement and delayed migration
Understanding relationships between infection and wildlife movement patterns is important for predicting pathogen spread, especially for multispecies pathogens and those that can spread to humans and domestic animals, such as avian influenza viruses (AIVs). Although infection with low pathogenic AIVs is generally considered asymptomatic in wild birds, prior work has shown that influenza-infected bDabbling duck eggs hatch after nest abandonment in the wild
In most birds, parental incubation of eggs is necessary for embryo development and survival. Using a combination of weekly nest visits, temperature dataloggers, infrared video cameras, and GPS tracking of hens, we documented several instances of duck eggs hatching after being abandoned by the incubating female. Of 2826 Mallard (Anas platyrhynchos) and Gadwall (Mareca strepera) nests monitored 2015Postbreeding movements and molting ecology of female gadwalls and mallards
The wing molt is an important annual life-history event that occurs in waterfowl and molt site selection can play an important role in determining survival. We tracked postbreeding movements of gadwall (Mareca strepera) and mallard (Anas platyrhynchos) females that bred in the Suisun Marsh (Suisun) of California, USA, to determine molt site selection and wing molt chronology. We attached backpackPredator movements in relation to habitat features reveal vulnerability of duck nests to predation
Nest predation is the main cause of nest failure for ducks. Understanding how habitat features influence predator movements may facilitate management of upland and wetland breeding habitats that reduces predator encounter rates with duck nests and increases nest survival rates. For 1618 duck nests, nest survival increased with distance to phragmites (Phragmites australis), shrubs, telephone poles,Avian influenza antibody prevalence increases with mercury contamination in wild waterfowl
Environmental contamination is widespread and can negatively impact wildlife health. Some contaminants, including heavy metals, have immunosuppressive effects, but prior studies have rarely measured contamination and disease simultaneously, which limits our understanding of how contaminants and pathogens interact to influence wildlife health. Here, we measured mercury concentrations, influenza infSpatiotemporal changes in influenza A virus prevalence among wild waterfowl inhabiting the continental United States throughout the annual cycle
Avian influenza viruses can pose serious risks to agricultural production, human health, and wildlife. An understanding of viruses in wild reservoir species across time and space is important to informing surveillance programs, risk models, and potential population impacts for vulnerable species. Although it is recognized that influenza A virus prevalence peaks in reservoir waterfowl in late summeMercury contamination and potential health risks to Arctic seabirds and shorebirds
Since the last Arctic Monitoring and Assessment Programme (AMAP) effort to review biological effects of mercury (Hg) on Arctic biota in 2011 and 2018, there has been a considerable number of new Arctic bird studies. This review article provides contemporary Hg exposure and potential health risk for 36 Arctic seabird and shorebird species, representing a larger portion of the Arctic than during preMachine learned daily life history classification using low frequency tracking data and automated modelling pipelines: Application to North American waterfowl
BackgroundIdentifying animal behaviors, life history states, and movement patterns is a prerequisite for many animal behavior analyses and effective management of wildlife and habitats. Most approaches classify short-term movement patterns with high frequency location or accelerometry data. However, patterns reflecting life history across longer time scales can have greater relevance to species biQuantitative meta-analysis reveals no association between mercury contamination and body condition in birds
Mercury contamination is a major threat to the global environment, and is still increasing in some regions despite international regulations. The methylated form of mercury is hazardous to biota, yet its sublethal effects are difficult to detect in wildlife. Body condition can vary in response to stressors, but previous studies have shown mixed effects of mercury on body condition in wildlife. UsiPathways for avian influenza virus spread: GPS reveals wild waterfowl in commercial livestock facilities and connectivity with the natural wetland landscape
Zoonotic diseases are of considerable concern to the human population and viruses such as avian influenza (AIV) threaten food security, wildlife conservation and human health. Wild waterfowl and the natural wetlands they use are known AIV reservoirs, with birds capable of virus transmission to domestic poultry populations. While infection risk models have linked migration routes and AIV outbreaks,Host correlates of avian influenza virus infection in wild waterfowl of the Sacramento Valley, California
Avian influenza viruses (AIVs) are distributed globally in members of the family Anatidae (waterfowl), and significant disease may occur when these viruses infect commercial poultry or humans. Early detection of AIV through surveillance of wild waterfowl is one measure to prevent future disease outbreaks. Surveillance efforts that are designed to account for host and environmental determinants of - Web Tools
Re-establishing Waterbird Breeding Colonies in San Francisco Bay
This U.S. Geological Survey (USGS), Western Ecological Research Center (WERC) story map details how partners are using science and management to maintain and establish new bird nesting colonies in support of the South Bay Salt Pond Restoration Project. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
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