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Herpetological Research Team (FRESC) Active

By Forest and Rangeland Ecosystem Science Center September 20, 2017

The Herpetological Research Team focuses on issues related to conservation and management of amphibians and other aquatic and semi-aquatic species. Among our current studies are effects of invasive species, disease, and land use change on the dynamics of amphibian communities to inform conservation and management decision making.

Many of our projects are supported by the USGS Amphibian Research and Monitoring Initiative (ARMI). ARMI works with Department of Interior (DOI) and other federal and state agencies to respond to information gaps that are critical to the implementation of effective conservation and management strategies for amphibian communities. ARMI’s work includes research on the status and threats of native species, development and evaluation of quantitative and field methods, and monitoring designs to address conservation and management information needs at multiple spatial and temporal scales.

Principal Investigator

Michael Adams  - Supervisory Research Ecologist

Federal Staff

Brome McCreary - Wildlife Biologist

Christopher Pearl - Wildlife Biologist

Jennifer Rowe - Wildlife Biologist

Affiliate

Adam Duarte - Research Ecologist at Oregon State University

 

 

 

Science Themes of the FRESC Herpetological Research Team are highlighted below.

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An American bullfrog.

American Bullfrog Invasion and Impacts on Native Species in the Pacific Northwest

The Herpetological Research Team at the USGS Forest and Rangeland Ecosystem Science Center uses innovative tools to investigate the invasion and spread of American bullfrogs in Washington and Oregon and understand how bullfrogs are interacting with native amphibians.
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Forest and Rangeland Ecosystem Science Center
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American Bullfrog Invasion and Impacts on Native Species in the Pacific Northwest

The Herpetological Research Team at the USGS Forest and Rangeland Ecosystem Science Center uses innovative tools to investigate the invasion and spread of American bullfrogs in Washington and Oregon and understand how bullfrogs are interacting with native amphibians.
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Parameterization of spatial multistate occupancy model for estimation of probability of Oregon spotted frog reproduction

Quantitative and Other Methods

Applying quantitative methods to evaluate ecological hypotheses for wild animal populations is inherently challenging due to the complexity of ecological systems and the sampling process that is used to monitor them.
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Ecosystems Mission Area, Species Management Research Program, Forest and Rangeland Ecosystem Science Center
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Quantitative and Other Methods

Applying quantitative methods to evaluate ecological hypotheses for wild animal populations is inherently challenging due to the complexity of ecological systems and the sampling process that is used to monitor them.
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Testing for Bsal

Disease

Disease is a major threat facing amphibian and reptile populations around the world. Our research addresses interactions between pathogens, the environment, and hosts to better understand ways to prevent the spread of disease.
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Forest and Rangeland Ecosystem Science Center
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Disease

Disease is a major threat facing amphibian and reptile populations around the world. Our research addresses interactions between pathogens, the environment, and hosts to better understand ways to prevent the spread of disease.
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Oregon Spotted Frog

The Oregon spotted frog (Rana pretiosa) is a medium-sized anuran native to the northwestern United States. Body coloration ranges from brown or tan to brick red, usually overlaid with dark, ragged spots. Oregon spotted frogs can be distinguished from other native species by their relatively short hind legs, orange or red wash of color on underside of abdomen and legs, and upturned chartreuse eyes...
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Species Management Research Program, Forest and Rangeland Ecosystem Science Center
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Oregon Spotted Frog

The Oregon spotted frog (Rana pretiosa) is a medium-sized anuran native to the northwestern United States. Body coloration ranges from brown or tan to brick red, usually overlaid with dark, ragged spots. Oregon spotted frogs can be distinguished from other native species by their relatively short hind legs, orange or red wash of color on underside of abdomen and legs, and upturned chartreuse eyes...
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Mink Lake Basin, Oregon

Aquatic Habitats and Communities

The Pacific Northwest includes a patchwork of public lands managed by numerous state and federal agencies. Our research informs and supports these agencies as they conserve and manage native amphibian species, including pre- and post-treatment assessment, decision support, long-term monitoring, population translocation, and habitat restoration.
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Forest and Rangeland Ecosystem Science Center
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Aquatic Habitats and Communities

The Pacific Northwest includes a patchwork of public lands managed by numerous state and federal agencies. Our research informs and supports these agencies as they conserve and manage native amphibian species, including pre- and post-treatment assessment, decision support, long-term monitoring, population translocation, and habitat restoration.
Learn More
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Foothill yellow-legged frog

Declining Amphibians

Amphibian populations world-wide are declining for reasons that include disease, habitat loss, and invasive species. Our research addresses these threats as part of the Amphibian Research and Monitoring Initiative (ARMI), a nationwide, federally funded program. We work with resource managers to provide information that improves understanding of status of amphibians and the implications of...
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Biological Threats and Invasive Species Research Program, Species Management Research Program, Forest and Rangeland Ecosystem Science Center
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Declining Amphibians

Amphibian populations world-wide are declining for reasons that include disease, habitat loss, and invasive species. Our research addresses these threats as part of the Amphibian Research and Monitoring Initiative (ARMI), a nationwide, federally funded program. We work with resource managers to provide information that improves understanding of status of amphibians and the implications of...
Learn More
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Bullfrog Young Adult

Aquatic Invasive Species

Aquatic invasive species, like bullfrogs, stocked fish, crayfish, and reed canarygrass can affect aquatic systems in a variety of ways and have been linked to declines in some amphibians.
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Biological Threats and Invasive Species Research Program, Forest and Rangeland Ecosystem Science Center
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Aquatic Invasive Species

Aquatic invasive species, like bullfrogs, stocked fish, crayfish, and reed canarygrass can affect aquatic systems in a variety of ways and have been linked to declines in some amphibians.
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If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.

Filter Total Items: 17

Oregon spotted frog (Rana pretiosa) telemetry and habitat use at Crane Prairie Reservoir in Oregon, USA

We used radio-telemetry to study late-season movement and habitat use by Oregon spotted frogs (Rana pretiosa) at Crane Prairie Reservoir in Oregon. This dataset includes individual frog location data and habitat use during each tracking event that occurred roughly weekly between September and late November of 2018.
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Forest and Rangeland Ecosystem Science Center

Oregon spotted frog (Rana pretiosa) observations in Oregon (ver. 5.0, January 2023)

This dataset contains information from surveys conducted 2016-2022 by USGS as part of an ongoing Oregon spotted frog (Rana pretiosa) monitoring effort in Oregon. USGS research activities 2016-2022 were divided into seven study design categories: breeding (egg mass counts), mid-level (visual encounter surveys for occupancy monitoring), apex (mark-recapture), telemetry, trapping, water quality (skin
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Forest and Rangeland Ecosystem Science Center

Annotated bibliography of grazing effects on amphibians and their habitats (ver. 2.0, February 2022)

This database contains literature citations and associated summaries pertaining to livestock grazing effects on amphibians and their habitats, with an emphasis on the Oregon spotted frog (Rana pretiosa) and other listed/sensitive wetland-breeding amphibians in the western United States. This is not meant to be an exhaustive list, nor did we perform a systematic meta-analysis; rather, literature re
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Forest and Rangeland Ecosystem Science Center

Capture-mark-recapture data for Oregon spotted frogs (Rana pretiosa) along the Deschutes River, Oregon, 2016-2019

This dataset contains information from capture-mark-recapture sampling of Oregon spotted frogs (Rana pretiosa) conducted 2016-2019 by USGS as part of a study relating R. pretiosa survival and abundance to wetland inundation in the upper Deschutes River. Data consist of site, survey, habitat, and species detection covariates, as well as 10 years of hydrological and drought metrics used to establish
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Forest and Rangeland Ecosystem Science Center

North Coast and Cascades Network consolidated amphibian database (1984-2005)

This data set is an amalgamation of twenty-nine original data sets, which represent amphibian surveys in the seven national parks comprising the North Coast and Cascades Network (NCCN) of the National Park Service. The data were collected from 1984-2005, and include the localities of 19 species of amphibians at various life stages, 18 native to the Pacific Northwest and one invasive species.
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Forest and Rangeland Ecosystem Science Center

Oregon spotted frog (Rana pretiosa) monitoring data for metademographic analysis 2010-2018, Oregon

This dataset contains information from surveys conducted 2010-2018 by USGS as part of a long-term Oregon spotted frog monitoring effort in the central Oregon range. Data consist of site, survey, habitat, and species detection covariates, as well as inter-site distance measurements.
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Forest and Rangeland Ecosystem Science Center

Oregon spotted frog (Rana pretiosa) telemetry and habitat use at Klamath Marsh National Wildlife Refuge in Oregon, USA

We used radio-telemetry to study late-season movement and habitat use by Oregon spotted frogs (Rana pretiosa) at Klamath Marsh National Wildlife Refuge in Oregon. This data release includes frog location and habitat use data, as well as visualizations of telemetry data. Tracking events occurred roughly weekly between August and December of 2017.
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Forest and Rangeland Ecosystem Science Center

Nutrients, estrogenicity, and fecal indicators in surface water collected from wetlands in the Klamath Marsh National Wildlife Refuge, Oregon, 2017-2018

The data was gathered to determine the effects of cattle grazing on wetland water quality in the Klamath National Wildlife Refuge in Oregon. Surface water samples from sites representing a range of grazing histories were collected between June and October in 2017 and 2018. Samples were analyzed for nutrients (ammonia, nitrate plus nitrite, nitrite and orthophosphate), total coliforms, E. coli, ent
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Forest and Rangeland Ecosystem Science Center

Amphibian capture mark-recapture

These data represent capture mark recapture data along with associated disease status for boreal toads (Anaxyrus boreas) from Wyoming and Montana from 2004-2016 and four frog species (Rana draytonii, R. muscosa, R. pretiosa, R. sierrae) from 2001-2016.
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Species Management Research Program, National Wildlife Health Center

Trask Watershed Study Amphibian Survival and Movement Data, 2008-2015

This data set contains mark-recapture information for individuals of Dicamptodon tenebrosus and Ascaphus truei marked for individual recognition. Amphibians represented in this data set were captured in 14 first-order perennial and seasonally intermittent streams in the East Fork of the South Fork of the Trask River in the northern Oregon Coast Range. Individuals are larval and mature aquatic Dica
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Forest and Rangeland Ecosystem Science Center

Terrestrial salamander captures after the 2003 Clark Fire, Willamette National Forest, OR

Data are the result of fixed-area, time-constrained searches for terrestrial salamanders within and nearby a wildfire-affected area of the Willamette National Forest, OR. The spatial extent of the study was within one kilometer of the border of the Clark fire that burned an area of 2,009 ha in 2003. Site surveys occurred during March and April, 2005. An important feature of the data is that 100m2
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Forest and Rangeland Ecosystem Science Center

Long-term amphibian monitoring data from the Willamette Valley, Oregon (2004-2015)

This dataset contains information from surveys conducted 2004-2015 by USGS as part of a long-term amphibian monitoring effort in the Willamette Valley, Oregon. Data consist of site, survey, habitat, and species detection covariates.
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Forest and Rangeland Ecosystem Science Center

If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.

Early action to address an emerging wildlife disease

A deadly fungal pathogen, Batrachochytrium salamandrivorans (Bsal) that affects amphibian skin was discovered during a die-off of European fire salamanders (Salamandra salamandra) in 2014. This pathogen has the potential to worsen already severe worldwide amphibian declines. Bsal is a close relative to another fungal disease known as Batrachochytrium dendrobatidis (Bd). Many scientists consider Bd
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M. J. Adams, M. Camille Harris, Daniel A. Grear
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Forest and Rangeland Ecosystem Science Center, National Wildlife Health Center
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Late season movement and habitat use by Oregon spotted frog (Rana pretiosa) in a large reservoir in Oregon, USA

Dam-created reservoirs are common landscape features that can provide habitat for amphibians, but their water level fluctuations and nonnative predators can differ markedly from more natural habitats. We compared fall movement and habitat use by the Oregon Spotted Frog (Rana pretiosa) in the reservoir pool with nearby river and pond habitats at Crane Prairie Reservoir in central Oregon, USA. Movem
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Christopher Pearl, Jennifer Rowe, Brome McCreary, Michael Adams
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Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Looking ahead, guided by the past: The role of U.S. national parks in amphibian research and conservation

Protected areas like national parks are essential elements of conservation because they limit human influence on the landscape, which protects biodiversity and ecosystem function. The role of national parks in conservation, however, often goes far beyond limiting human influence. The U.S. National Park Service and its system of land units contribute substantively to conservation by providing prote
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Brian J. Halstead, Andrew M. Ray, Erin L. Muths, Evan H. Campbell Grant, Rob Grasso, Michael Adams, Kathleen Semple Delaney, Jane Carlson, Blake R. Hossack
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Ecosystems Mission Area, Western Ecological Research Center (WERC)

An updated assessment of status and trend in the distribution of the Cascades frog (Rana cascadae) in Oregon, USA

Conservation efforts need reliable information concerning the status of a species and their trends to help identify which species are in most need of assistance. We completed a comparative evaluation of the occurrence of breeding for Cascades Frog (Rana cascadae), an amphibian that is being considered for federal protection under the U.S. Endangered Species Act. Specifically, in 2018–2019 we resur
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Adam Duarte, Christopher Pearl, Brome McCreary, Jennifer Rowe, Michael Adams
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Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Demography of the Oregon spotted frog along a hydrologically modified river

Altered flow regimes can contribute to dissociation between life history strategies and environmental conditions, leading to reduced persistence reported for many wildlife populations inhabiting regulated rivers. The Oregon spotted frog (Rana pretiosa) is a threatened species occurring in floodplains, ponds, and wetlands in the Pacific Northwest with a core range in Oregon, USA. All life stages of
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Jennifer Rowe, Adam Duarte, Christopher Pearl, Brome McCreary, Patricia Haggerty, John W. Jones, Michael Adams
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Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Enhanced between-site biosecurity to minimize herpetofaunal disease-causing pathogen transmission

Pathogens and their associated diseases have the potential to severely affect wildlife populations, including herpetofauna. Concern is increasing for transmission pathways of herpetofaunal diseases, especially for amphibians affected by the fungal pathogens Batrachochytrium dendrobatidis (Bd: Longcore et al. 1999) and B. salamandrivorans (Bsal: Martel et al. 2013), and amphibians and reptiles affe
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Deanna H. Olson, Katherine H. Haman, Matthew J. Gray, Reid N. Harris, Tracy Thompson, Marley Iredale, Michelle Christman, Jennifer M. Williams, Michael Adams, Jennifer R. Ballard
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Forest and Rangeland Ecosystem Science Center

Monitoring wetland water quality related to livestock grazing in amphibian habitats

Land use alteration such as livestock grazing can affect water quality in habitats of at-risk wildlife species. Data from managed wetlands are needed to understand levels of exposure for aquatic life stages and monitor grazing-related changes afield. We quantified spatial and temporal variation in water quality in wetlands occupied by threatened Oregon spotted frog (Rana pretiosa) at Klamath Marsh
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Kelly Smalling, Jennifer Rowe, Christopher Pearl, Luke R. Iwanowicz, Carrie E. Givens, Chauncey W. Anderson, Brome McCreary, Michael Adams
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Ecosystems Mission Area, Water Resources Mission Area, Eastern Ecological Science Center, Forest and Rangeland Ecosystem Science Center, New Jersey Water Science Center, Oregon Water Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Batrachochytrium salamandrivorans (Bsal) not detected in an intensive survey of wild North American amphibians

The salamander chytrid fungus (Batrachochytrium salamandrivorans [Bsal]) is causing massive mortality of salamanders in Europe. The potential for spread via international trade into North America and the high diversity of salamanders has catalyzed concern about Bsal in the U.S. Surveillance programs for invading pathogens must initially meet challenges that include low rates of occurrence on the l
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Hardin Waddle, Daniel A. Grear, Brittany Mosher, Evan H. Campbell Grant, Michael Adams, Adam R. Backlin, William Barichivich, Adrianne B. Brand, Gary M. Bucciarelli, Daniel L. Calhoun, Tara Chestnut, Jon M. Davenport, Andrew E. Dietrich, Robert N. Fisher, Brad Glorioso, Brian J. Halstead, Marc P Hayes, R. Ken Honeycutt, Blake R. Hossack, Patrick M. Kleeman, Julio A. Lemos-Espinal, Jeffrey M. Lorch, Robert W. Atkinson, Erin L. Muths, Christopher Pearl, Katherine Richgels, Charles W Robinson, Mark F. Roth, Jennifer Rowe, Walter Sadinski, Brent H. Sigafus, Iga Stasiak, Samuel Sweet, Susan C. Walls, Gregory J Watkins-Colwell, C. LeAnn White, Lori A Williams, Megan E. Winzeler
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Ecosystems Mission Area, Eastern Ecological Science Center, National Wildlife Health Center, Northern Rocky Mountain Science Center, Upper Midwest Environmental Sciences Center, Western Ecological Research Center (WERC), Wetland and Aquatic Research Center

Oregon spotted frog (Rana pretiosa) migration from an aquatic overwintering site: Timing, duration, and potential environmental cues

Relatively few North American anurans overwinter in water and information is sparse on their movement from overwintering habitat to breeding sites. Oregon spotted frogs (Rana pretiosa) breed explosively in early spring and often overwinter submerged at sites that are distanced from breeding habitats. In montane parts of their range, wintering and breeding habitats can remain frozen for months. We
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Jay Bowerman, Christopher Pearl
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Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Estimation of metademographic rates and landscape connectivity for a conservation-reliant anuran

ContextAmphibian conservation efforts commonly assume populations are tied to waterbodies that collectively function as a metapopulation. This assumption is rarely evaluated, and there is a need to understand the degree of connectivity among patches to appropriately define, manage, and conserve biological populations.ObjectivesOur objectives were to quantify local persistence, colonization, and re
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Adam Duarte, James Peterson, Christopher Pearl, Jennifer Christine Rowe, Brome McCreary, Stephanie Galvan, Michael Adams
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Ecosystems Mission Area, Cooperative Research Units, Forest and Rangeland Ecosystem Science Center

Amphibian chytrid prevalence on boreal toads in SE Alaska and NW British Columbia: Tests of habitat, life stages, and temporal trends

Tracking and understanding variation in pathogens such as Batrachochytrium dendrobatidis ([Bd]), which causes amphibian chytridiomycosis and has caused population declines globally, is a priority for many land managers. However, there has been relatively little sampling of amphibian communities at high latitudes. We used skin swabs collected during 2005–2017 from boreal toads (Anaxyrus boreas; N =
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Blake R. Hossack, Michael Adams, R Ken Honeycutt, Jami J Belt, S Pyare
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Ecosystems Mission Area, Northern Rocky Mountain Science Center

Batrachochytrium salamandriovrans (Bsal) in Appalachia—Using scenario building to proactively prepare for a wildlife disease outbreak caused by an invasive amphibian chytrid fungus

Batrachochytrium salamandrivorans (Bsal), a pathogenic chytrid fungus, is nonnative to the United States and poses a disease threat to vulnerable amphibian hosts. The Bsal fungus may lead to increases in threatened, endangered, and sensitive status listings at State, Tribal, and Federal levels, resulting in financial costs associated with implementing the Endangered Species Act of 1973. The United
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M. Camille Hopkins, M. J. Adams, P.E. Super, D.H. Olson, C.R. Hickman, P. English, L. Sprague, I.B. Maska, A.B. Pennaz, K. A. Ludwig
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program

Effect of amphibian chytrid fungus (Batrachochytrium dendrobatidis) on apparent survival of frogs and toads in the western USA

Despite increasing interest in determining the population-level effects of emerging infectious diseases on wildlife, estimating effects of disease on survival rates remains difficult. Even for a well-studied disease such as amphibian chytridiomycosis (caused by the fungus Batrachochytrium dendrobatidis [Bd]), there are few estimates of how survival of wild hosts is affected. We applied hierarchica
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Robin E. Russell, Brian J. Halstead, Brittany Mosher, Erin L. Muths, Michael Adams, Evan H. Campbell Grant, Robert N. Fisher, Patrick M. Kleeman, Adam R. Backlin, Christopher Pearl, R. Ken Honeycutt, Blake R. Hossack
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Ecosystems Mission Area, Eastern Ecological Science Center, Forest and Rangeland Ecosystem Science Center, Fort Collins Science Center, National Wildlife Health Center, Northern Rocky Mountain Science Center, Western Ecological Research Center (WERC)

Below are news stories associated with this project.

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Image of Mike Adams

ARMI Scientist Michael Adams Receives 2020 PARC Honor

Dr. Michael Adams, Lead for the USGS Amphibian Research and Monitoring Initiative (ARMI) and Supervisory Research Ecologist at the USGS Forest and Rangeland Ecosystem Science Center, has been selected to receive the 2020 Partners in Amphibian and Reptile Conservation (PARC) Alison Haskell Award for Excellence in Herpetofaunal Conservation. 

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Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center
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Annotated Bibliography: Grazing Effects on Amphibians and Their Habitats

Livestock grazing is one of the most common land uses in the western United States, where multiple amphibians of conservation concern use habitats...

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Invasive Amphibian Fungus Could Threaten US Salamander Populations

A deadly fungus causing population crashes in wild European salamanders could emerge in the United States and threaten already declining amphibians...

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