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Susan Walls, Ph.D.

Susan Walls is a research wildlife biologist who serves as the coordinator and lead scientist for the southeastern region of the Amphibian Research and Monitoring Initiative (ARMI). 

ARMI is a national program for which funding was appropriated by Congress in 2000 in response to mounting evidence and concern for declines of amphibians in the U.S. and worldwide. Susan's research group establishes and implements long-term monitoring of amphibians at key sites within the southeastern U.S. (AL, GA, FL, SC, NC and TN) and conducts research on potential causes of declines. The team focuses on model-based monitoring to assess the impacts of climate change, emerging diseases, habitat restoration, and invasive species on amphibian communities.

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Filter Total Items: 47

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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Ecosystems, Eastern Ecological Science Center, National Wildlife Health Center, Northern Rocky Mountain Science Center, Patuxent Wildlife Research Center, Upper Midwest Environmental Sciences Center, Western Ecological Research Center (WERC), Wetland and Aquatic Research Center

Editorial: Contributions of behavior and physiology to conservation biology

Conservation biology is a rapidly evolving discipline, with its synthetic, multidisciplinary framework expanding extensively in recent years. Seemingly disparate disciplines, such as behavior and physiology, are being integrated into this discipline's growing portfolio, resulting in diverse tools that can help develop conservation solutions. Behavior and physiology have traditionally been consider
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Ecosystems, Wetland and Aquatic Research Center

Category count models for adaptive management of metapopulations: Case study of an imperiled salamander

Managing spatially structured populations of imperiled species presents many challenges. Spatial structure can make it difficult to predict population responses to potential recovery activities, and learning through experimentation may not be advised if it could harm threatened populations. Adaptive management provides an appealing framework when experimentation is considered too risky or time con
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Ecosystems, Wetland and Aquatic Research Center

Integrating behavior and physiology into strategies for amphibian conservation

The amphibian decline crisis has been challenging to address because of the complexity of factors—and their multitude of interactive effects—that drive this global issue. Dissecting such complexity could benefit from strategies that integrate multiple disciplines and address the mechanistic underpinnings of population declines and extirpations. We examine how the disciplines of behavior and physio
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Ecosystems, Wetland and Aquatic Research Center

Seeking shelter from the storm: Conservation and management of imperiled species in a changing climate

Climate change is anticipated to exacerbate the extinction risk of species whose persistence is already compromised by habitat loss, invasive species, disease, or other stressors. In coastal areas of the southeastern United States (USA), many imperiled vertebrates are vulnerable to hurricanes, which climate models predict to become more severe in the 21st century. Despite this escalating threat, e
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Ecosystems, Wetland and Aquatic Research Center

A new parameterization for estimating co‐occurrence of interacting species

Models currently used to estimate patterns of species co‐occurrence while accounting for errors in detection of species can be difficult to fit when the effects of covariates on species occurrence probabilities are included. The source of the estimation problems is the particular parameterization used to specify species co‐occurrence probability. We develop a new parameterization for estimating pa
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Ecosystems, Wetland and Aquatic Research Center

Linking variability in climate to wetland habitat suitability: Is it possible to forecast regional responses from simple climate measures?

Temporary wetlands have value to both ecological and social systems. Interactions between local climate and the surrounding landscape result in patterns of hydrology that are unique to temporary wetlands. These seasonal and annual fluctuations in wetland inundation contribute to community composition and richness. Thus, predicting wetland community responses to environmental change is tied to the
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Ecosystems, Eastern Ecological Science Center, Western Ecological Research Center (WERC), Patuxent Wildlife Research Center

Identifying management-relevant research priorities for responding to disease-associated amphibian declines

A research priority can be defined as a knowledge gap that, if resolved, identifies the optimal course of conservation action. We (a group of geographically distributed and multidisciplinary research scientists) used tools from nominal group theory and decision analysis to collaboratively identify and prioritize information needs within the context of disease-associated amphibian decline, in order
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Ecosystems, Water Resources, Fish & Wildlife Disease, Wildlife Program, Eastern Ecological Science Center, Forest and Rangeland Ecosystem Science Center, Fort Collins Science Center, National Wildlife Health Center, New Jersey Water Science Center, Northern Rocky Mountain Science Center, Patuxent Wildlife Research Center, Western Ecological Research Center (WERC), Wetland and Aquatic Research Center

Quantifying climate sensitivity and climate-driven change in North American amphibian communities

Changing climate will impact species’ ranges only when environmental variability directly impacts the demography of local populations. However, measurement of demographic responses to climate change has largely been limited to single species and locations. Here we show that amphibian communities are responsive to climatic variability, using >500,000 time-series observations for 81 species across 8
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Ecosystems, Water Resources, Wildlife Program, Eastern Ecological Science Center, Forest and Rangeland Ecosystem Science Center, Fort Collins Science Center, Northern Rocky Mountain Science Center, Patuxent Wildlife Research Center, South Atlantic Water Science Center (SAWSC), Southwest Biological Science Center, Upper Midwest Environmental Sciences Center, Western Ecological Research Center (WERC), Wetland and Aquatic Research Center , John Wesley Powell Center for Analysis and Synthesis

Coping with constraints: Achieving effective conservation with limited resources

Conservation resources have become increasingly limited and, along with social, cultural and political complexities, this shortfall frequently challenges effectiveness in conservation. Because conservation can be costly, efforts are often only initiated after a species has declined below a critical threshold and/or when statutory protection is mandated. However, implementing conservation proactive
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Ecosystems, Wetland and Aquatic Research Center

Book review: Behavioral ecology of the eastern red-backed salamander: 50 years of research

In commemoration of the 100th anniversary of the British Ecological Society, Sutherland et al. (2013) identified 100 questions of fundamental significance in “pure” (i.e., not applied) ecology. A somewhat unexpected outcome of these authors’ exercise was the realization that, after 100 years of comprehensive, intensive scientific research, there remained “profound knowledge gaps” in ecology, such
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Ecosystems, Wetland and Aquatic Research Center

A new framework for analysing automated acoustic species detection data: Occupancy estimation and optimization of recordings post-processing

The development and use of automated species-detection technologies, such as acoustic recorders, for monitoring wildlife are rapidly expanding. Automated classification algorithms provide a cost- and time-effective means to process information-rich data, but often at the cost of additional detection errors. Appropriate methods are necessary to analyse such data while dealing with the different typ
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Ecosystems, Wetland and Aquatic Research Center
Filter Total Items: 13
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Rimrock crowned snake

Informing Future Condition Scenario Planning for Habitat Specialists of the Imperiled Pine Rockland Ecosystem of South Florida

South Florida's pine rockland ecosystem represents less than 3% of its original extent. This project will evaluate habitat conditions for two pine rockland snake species to develop future habitat condition scenarios for Species Status Assessments.
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Ecosystems, Wetland and Aquatic Research Center
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Informing Future Condition Scenario Planning for Habitat Specialists of the Imperiled Pine Rockland Ecosystem of South Florida

South Florida's pine rockland ecosystem represents less than 3% of its original extent. This project will evaluate habitat conditions for two pine rockland snake species to develop future habitat condition scenarios for Species Status Assessments.
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Longleaf Pine forest in Florida

Developing Future Habitat Condition Scenarios for Wildlife in the Imperiled Pine Rockland Ecosystem of South Florida

The pine rockland ecosystem is found only in south Florida and the Bahamas and provides important habitat for numerous rare and endemic plants and animals. These include 18 species that are already federally listed as threatened or endangered and four other species petitioned for listing that are scheduled for development of Species Status Assessments (SSAs). Today, south Florida’s pine rockland e...
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Climate Adaptation Science Centers, Climate Adaptation Science Center
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Developing Future Habitat Condition Scenarios for Wildlife in the Imperiled Pine Rockland Ecosystem of South Florida

The pine rockland ecosystem is found only in south Florida and the Bahamas and provides important habitat for numerous rare and endemic plants and animals. These include 18 species that are already federally listed as threatened or endangered and four other species petitioned for listing that are scheduled for development of Species Status Assessments (SSAs). Today, south Florida’s pine rockland e...
Learn More
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Longleaf Pine forest in Florida

Developing Future Habitat Condition Scenarios for Wildlife in the Imperiled Pine Rockland Ecosystem of South Florida

The pine rockland ecosystem is found only in south Florida and the Bahamas and provides important habitat for numerous rare and endemic plants and animals. These include 18 species that are already federally listed as threatened or endangered and four other species petitioned for listing that are scheduled for development of Species Status Assessments (SSAs). Today, south Florida’s pine rockland e...
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Climate Adaptation Science Centers, Climate Adaptation Science Center
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Developing Future Habitat Condition Scenarios for Wildlife in the Imperiled Pine Rockland Ecosystem of South Florida

The pine rockland ecosystem is found only in south Florida and the Bahamas and provides important habitat for numerous rare and endemic plants and animals. These include 18 species that are already federally listed as threatened or endangered and four other species petitioned for listing that are scheduled for development of Species Status Assessments (SSAs). Today, south Florida’s pine rockland e...
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Ornate Chorus Frog, Pseudacris ornata

Monitoring of Amphibians at St. Marks National Wildlife Refuge in Northwest Florida

Freshwater wetlands provide critical habitat for a diverse array of organisms, including many amphibians. Yet, under the threat of climate change, these habitats are among the most imperiled ecosystems on Earth.
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Ecosystems, Wildlife Program, Wetland and Aquatic Research Center
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Monitoring of Amphibians at St. Marks National Wildlife Refuge in Northwest Florida

Freshwater wetlands provide critical habitat for a diverse array of organisms, including many amphibians. Yet, under the threat of climate change, these habitats are among the most imperiled ecosystems on Earth.
Learn More
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Population Demography and Food Web Analysis of Large Aquatic Salamanders (Siren and Amphiuma) in North Florida

Population Demography and Food Web Analysis of Large Aquatic Salamanders (Siren and Amphiuma) in North Florida

Understanding amphibian's life-histories can help predict how they may persist in aquatic habitats in the face of droughts and other climate change-associated events.
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Ecosystems, Wildlife Program, Wetland and Aquatic Research Center
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Population Demography and Food Web Analysis of Large Aquatic Salamanders (Siren and Amphiuma) in North Florida

Understanding amphibian's life-histories can help predict how they may persist in aquatic habitats in the face of droughts and other climate change-associated events.
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Frosted flatwoods salamander

Adaptive Habitat Conservation for Flatwoods Salamanders

USGS scientists investigate adaptive habitat conservation for Flatwoods salamanders.
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Ecosystems, Wildlife Program, Wetland and Aquatic Research Center
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Adaptive Habitat Conservation for Flatwoods Salamanders

USGS scientists investigate adaptive habitat conservation for Flatwoods salamanders.
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Evaluating the Prevalence of the Amphibian Chytrid Fungus, Batrachochytrium dendrobatidis, in the Southeastern U.S.: Any Evidenc

Evaluating the Prevalence of the Amphibian Chytrid Fungus, Batrachochytrium dendrobatidis, in the Southeastern U.S.: Any Evidence of Disease-Related Population Declines?

Pathogens and infectious disease play a role in some recent species extinctions and are likely to impact biodiversity in the future. Environmental DNA - eDNA - is coupled with traditional amphibian sampling methods to determine the distribution and prevalence of the amphibian chytrid fungus, also known as Bd, in the southeastern US.
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Ecosystems, Wildlife Program, Wetland and Aquatic Research Center
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Evaluating the Prevalence of the Amphibian Chytrid Fungus, Batrachochytrium dendrobatidis, in the Southeastern U.S.: Any Evidence of Disease-Related Population Declines?

Pathogens and infectious disease play a role in some recent species extinctions and are likely to impact biodiversity in the future. Environmental DNA - eDNA - is coupled with traditional amphibian sampling methods to determine the distribution and prevalence of the amphibian chytrid fungus, also known as Bd, in the southeastern US.
Learn More
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A Decision Support Tool for Repatriation of Aquatic Fauna: A Case Study Involving the Striped Newt (Notophthalmus perstriatus) a

A Decision Support Tool for Repatriation of Aquatic Fauna: A Case Study Involving the Striped Newt (Notophthalmus perstriatus) at St. Marks National Wildlife Refuge, Florida

The Striped Newt is a small salamander found in xeric habitats (e.g., scrub, sandhill, dry flatwoods) of the lower coastal plain and northern peninsular Florida. Though once considered "common," they are currently a candidate species for federal listing.
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Ecosystems, Wildlife Program, Wetland and Aquatic Research Center
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A Decision Support Tool for Repatriation of Aquatic Fauna: A Case Study Involving the Striped Newt (Notophthalmus perstriatus) at St. Marks National Wildlife Refuge, Florida

The Striped Newt is a small salamander found in xeric habitats (e.g., scrub, sandhill, dry flatwoods) of the lower coastal plain and northern peninsular Florida. Though once considered "common," they are currently a candidate species for federal listing.
Learn More
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Use of Amphibian Communities as Indicators of Restoration Success in the Greater Everglades

Use of Amphibian Communities as Indicators of Restoration Success in the Greater Everglades

Habitat alteration and climate, when combined, are serious threats to amphibians and other wildlife. Habitat suitability models are being used to predict the responses of an amphibian community to hydrological and habitat restoration in the Greater Everglades Ecosystem.
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Ecosystems, Wetland and Aquatic Research Center
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Use of Amphibian Communities as Indicators of Restoration Success in the Greater Everglades

Habitat alteration and climate, when combined, are serious threats to amphibians and other wildlife. Habitat suitability models are being used to predict the responses of an amphibian community to hydrological and habitat restoration in the Greater Everglades Ecosystem.
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USGS science for a changing world logo

Elucidating mechanisms underlying amphibian declines in North America using hierarchical spatial models

Amphibian populations are declining globally at unprecedented rates but statistically rigorous identification of mechanisms is lacking. Identification of reasons underlying large-scale declines is imperative to plan and implement effective conservation efforts. Most research on amphibian population decline has focused on local populations and local factors. However, the ubiquity of declines across
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John Wesley Powell Center for Analysis and Synthesis
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Elucidating mechanisms underlying amphibian declines in North America using hierarchical spatial models

Amphibian populations are declining globally at unprecedented rates but statistically rigorous identification of mechanisms is lacking. Identification of reasons underlying large-scale declines is imperative to plan and implement effective conservation efforts. Most research on amphibian population decline has focused on local populations and local factors. However, the ubiquity of declines across
Learn More
link
Coping with Invasive Alien Species and Environmental Stressors: Linking Behavioral Studies with Management for Anuran Amphibians

Coping with Invasive Alien Species and Environmental Stressors: Linking Behavioral Studies with Management for Anuran Amphibians

Climate change and invasive species are two key drivers of biodiversity loss. Knowing how amphibians respond to climate change and invasive species can greatly improve predictions of species' persistence in the face of these factors and can help guide resource managers and conservation biologists in developing strategies to manage for these encroaching disturbances.
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Ecosystems, Invasive Species Program, Wildlife Program, Wetland and Aquatic Research Center
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Coping with Invasive Alien Species and Environmental Stressors: Linking Behavioral Studies with Management for Anuran Amphibians

Climate change and invasive species are two key drivers of biodiversity loss. Knowing how amphibians respond to climate change and invasive species can greatly improve predictions of species' persistence in the face of these factors and can help guide resource managers and conservation biologists in developing strategies to manage for these encroaching disturbances.
Learn More
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Everglades - stock image

How will Florida’s Biodiversity Respond to Climate Change?

Florida is home to 50 endangered species, 23 National Wildlife Refuges, 9 national parks, and 119 state parks. Straddling both temperate and sub-tropical zones, the state is also unique in that it is a long and narrow peninsula, surrounded on three sides by warm water, creating a dynamic environment. The impacts of climate change, such as sea-level rise and severe storms, threaten the state’s uniq...
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Climate Adaptation Science Centers, Climate Adaptation Science Center
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How will Florida’s Biodiversity Respond to Climate Change?

Florida is home to 50 endangered species, 23 National Wildlife Refuges, 9 national parks, and 119 state parks. Straddling both temperate and sub-tropical zones, the state is also unique in that it is a long and narrow peninsula, surrounded on three sides by warm water, creating a dynamic environment. The impacts of climate change, such as sea-level rise and severe storms, threaten the state’s uniq...
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A Unified Research Strategy for Disease Management

As wildlife diseases increase globally, an understanding of host-pathogen relationships can elucidate avenues for management and improve conservation...

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Large-scale Review of Amphibian Species and Community Response to Climate Change

Amphibian species and community richness has been declining in North America and climate change may play a role in these declines. Global climate...

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