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.
Science and Products
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...
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.
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.
Adaptive Habitat Conservation for Flatwoods Salamanders
USGS scientists investigate adaptive habitat conservation for Flatwoods salamanders.
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...
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...
Fish, amphibian, and conductance data from Panacea Unit, St. Marks National Wildlife Refuge, FL, 2009-2016 Fish, amphibian, and conductance data from Panacea Unit, St. Marks National Wildlife Refuge, FL, 2009-2016
These data are meant to support a publication "Disentangling direct and indirect effects of extreme events on coastal wetland communities" in the Journal of Animal Ecology. This dataset contains both amphibian and fish observations based on our use of plastic minnow traps. Additionally we present (specific) conductance values observed during our trapping periods.
Data release for Predicting the impacts of future sea level rise on specialist snake species in the imperiled pine rockland ecosystem of South Florida Data release for Predicting the impacts of future sea level rise on specialist snake species in the imperiled pine rockland ecosystem of South Florida
Approximately 90% of pine rockland habitat in South Florida and the Florida Keys, USA, has been lost, fragmented, and degraded due to urbanization and other anthropogenic disturbances. Low-lying islands and coastal areas are also becoming increasingly vulnerable to sea-level rise and high tide flooding, which is rapidly increasing in frequency, depth, and extent, putting these areas and...
Corticosterone release rates, water quality, microbiome, and mucosome data for analysis of Pseudacris ornata sites Corticosterone release rates, water quality, microbiome, and mucosome data for analysis of Pseudacris ornata sites
We measured environmental variables at multiple spatial scales and their effect on three physiological health metrics of ornate chorus frog (Pseudacris ornata) tadpoles to identify potential correlates of population declines. To accomplish this, we measured corticosterone (glucocorticoid hormone associated with the stress response in amphibians) release rates, as well as the skin mucosal...
Specific conductance of flatwood salamander breeding ponds: pre- and post-Hurricane Michael, 2013-2018 Specific conductance of flatwood salamander breeding ponds: pre- and post-Hurricane Michael, 2013-2018
Hurricane Michael impacted the gulf coast of the southeastern USA in October 2018. During this storm, St. Marks National Wildlife Refuge, located along the northern Gulf of Mexico's coast in the panhandle region of Florida, experienced storm surge that was 2.3 to 3.3 m above sea level. Storm surge pushed sea water into some ephemeral freshwater ponds used for breeding by the federally...
Hydrological measurements of 300 US temporary wetlands from 2004-2014 Hydrological measurements of 300 US temporary wetlands from 2004-2014
This dataset includes hydrological measurements of 300 US temporary wetlands from 2004-2014.
Computer automated frog vocalization results from Picayune Strand State Forest, Florida 2011-2012 Computer automated frog vocalization results from Picayune Strand State Forest, Florida 2011-2012
This dataset includes the results of a computer automated anuran vocalization recognition analysis of audio recordings made at Picayune Strand State Forest in 2011 and 2012. The audio files were scanned for 11 species of frogs and toads using the commercially available software program Song Scope (ver. 4.1.3). All detections by the software are listed here along with a "result" field...
Filter Total Items: 61
Vulnerability of endemic insular mole skinks to sea-level rise Vulnerability of endemic insular mole skinks to sea-level rise
Although coastal islands are home to many endemic species, they are also at risk of inundation from storm surge and sea level rise. Three subspecies of mole skink (Plestiodon egregius egregius, P. e. insularis, and the Egmont Key Mole Skink known from a single occurrence) occur on a small number of islands off the Gulf Coast of Florida, USA. We used the most recent sea level rise...
Authors
Erin L. Koen, William Barichivich, Susan Walls
Climate change Climate change
Amphibian ecology and distribution are strongly correlated with climate. Regional patterns of amphibian biodiversity are intimately linked to temperature, evapotranspiration rate, and clines in humidity. While amphibians are and will continue to be adversely affected by recent and projected changes in climate, research suggests that adaptation may happen more slowly than the expected...
Authors
David Bickford, Guinevere O.U. Wogan, Deanna H. Olson, K.S. Seshadri, Mark C. Urban, Ana Carnaval, John Measey, Jodi J.L. Rowley, Sean Rovito, Rudolf von May, Susan Walls
The sands of time: Predicting sea level rise impacts to barrier island habitats The sands of time: Predicting sea level rise impacts to barrier island habitats
Coastal beach ecosystems support critical habitat for numerous species and are vulnerable to sea level rise. Sand beaches are spatially and temporally dynamic, making it difficult to accurately predict future habitat loss – estimates that are crucial as species are being assessed for protection. We mapped sand beach habitat on 12 focal barrier islands and low-lying beaches off the Gulf...
Authors
Erin L. Koen, William Barichivich, Susan Walls
Dietary niche of three omnivorous turtle species in a northern Florida river: Insights from stable isotope analysis Dietary niche of three omnivorous turtle species in a northern Florida river: Insights from stable isotope analysis
Macrochelys suwanniensis (Suwannee Alligator Snapping Turtle) coexists with 2 other native large omnivorous turtle species (Chelydra serpentina [Snapping Turtle] and Trachemys scripta scripta [Yellow-bellied Slider]) in a 9-km section of the Santa Fe River in northern Florida. A major shift in dominant submersed aquatic vegetation prompted us to quantify trophic position and niche...
Authors
Mathew Denton, Gerald R. Johnston, Travis M. Thomas, Hardin Waddle, Susan Walls, Kristen Hart
Disentangling direct and indirect effects of extreme events on coastal wetland communities Disentangling direct and indirect effects of extreme events on coastal wetland communities
One of the primary ways in which climate change will impact coastal freshwater wetlands is through changes in the frequency, intensity, timing and distribution of extreme weather events. Disentangling the direct and indirect mechanisms of population- and community-level responses to extreme events is vital to predicting how species composition of coastal wetlands will change under future
Authors
Courtney L. Davis, Susan E. Walls, William J. Barichivich, Mary Brown, David A.W. Miller
Future changes in habitat availability for two specialist snake species in the imperiled rocklands of South Florida, U.S.A. Future changes in habitat availability for two specialist snake species in the imperiled rocklands of South Florida, U.S.A.
Rockland habitat in South Florida, USA, is a threatened ecosystem that has been lost, fragmented, or degraded because of urbanization or other anthropogenic disturbance. Furthermore, low-lying islands and coastal areas are experiencing sea level rise (SLR) and an increased frequency and intensity of tidal flooding, putting rockland habitats there at increasing risk of ecological change...
Authors
Suresh C. Subedi, Susan C. Walls, William Barichivich, Ryan Boyles, Michael S. Ross, J. Aaron Hogan, John A. Tupy
Science and Products
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...
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.
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.
Adaptive Habitat Conservation for Flatwoods Salamanders
USGS scientists investigate adaptive habitat conservation for Flatwoods salamanders.
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...
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...
Fish, amphibian, and conductance data from Panacea Unit, St. Marks National Wildlife Refuge, FL, 2009-2016 Fish, amphibian, and conductance data from Panacea Unit, St. Marks National Wildlife Refuge, FL, 2009-2016
These data are meant to support a publication "Disentangling direct and indirect effects of extreme events on coastal wetland communities" in the Journal of Animal Ecology. This dataset contains both amphibian and fish observations based on our use of plastic minnow traps. Additionally we present (specific) conductance values observed during our trapping periods.
Data release for Predicting the impacts of future sea level rise on specialist snake species in the imperiled pine rockland ecosystem of South Florida Data release for Predicting the impacts of future sea level rise on specialist snake species in the imperiled pine rockland ecosystem of South Florida
Approximately 90% of pine rockland habitat in South Florida and the Florida Keys, USA, has been lost, fragmented, and degraded due to urbanization and other anthropogenic disturbances. Low-lying islands and coastal areas are also becoming increasingly vulnerable to sea-level rise and high tide flooding, which is rapidly increasing in frequency, depth, and extent, putting these areas and...
Corticosterone release rates, water quality, microbiome, and mucosome data for analysis of Pseudacris ornata sites Corticosterone release rates, water quality, microbiome, and mucosome data for analysis of Pseudacris ornata sites
We measured environmental variables at multiple spatial scales and their effect on three physiological health metrics of ornate chorus frog (Pseudacris ornata) tadpoles to identify potential correlates of population declines. To accomplish this, we measured corticosterone (glucocorticoid hormone associated with the stress response in amphibians) release rates, as well as the skin mucosal...
Specific conductance of flatwood salamander breeding ponds: pre- and post-Hurricane Michael, 2013-2018 Specific conductance of flatwood salamander breeding ponds: pre- and post-Hurricane Michael, 2013-2018
Hurricane Michael impacted the gulf coast of the southeastern USA in October 2018. During this storm, St. Marks National Wildlife Refuge, located along the northern Gulf of Mexico's coast in the panhandle region of Florida, experienced storm surge that was 2.3 to 3.3 m above sea level. Storm surge pushed sea water into some ephemeral freshwater ponds used for breeding by the federally...
Hydrological measurements of 300 US temporary wetlands from 2004-2014 Hydrological measurements of 300 US temporary wetlands from 2004-2014
This dataset includes hydrological measurements of 300 US temporary wetlands from 2004-2014.
Computer automated frog vocalization results from Picayune Strand State Forest, Florida 2011-2012 Computer automated frog vocalization results from Picayune Strand State Forest, Florida 2011-2012
This dataset includes the results of a computer automated anuran vocalization recognition analysis of audio recordings made at Picayune Strand State Forest in 2011 and 2012. The audio files were scanned for 11 species of frogs and toads using the commercially available software program Song Scope (ver. 4.1.3). All detections by the software are listed here along with a "result" field...
Filter Total Items: 61
Vulnerability of endemic insular mole skinks to sea-level rise Vulnerability of endemic insular mole skinks to sea-level rise
Although coastal islands are home to many endemic species, they are also at risk of inundation from storm surge and sea level rise. Three subspecies of mole skink (Plestiodon egregius egregius, P. e. insularis, and the Egmont Key Mole Skink known from a single occurrence) occur on a small number of islands off the Gulf Coast of Florida, USA. We used the most recent sea level rise...
Authors
Erin L. Koen, William Barichivich, Susan Walls
Climate change Climate change
Amphibian ecology and distribution are strongly correlated with climate. Regional patterns of amphibian biodiversity are intimately linked to temperature, evapotranspiration rate, and clines in humidity. While amphibians are and will continue to be adversely affected by recent and projected changes in climate, research suggests that adaptation may happen more slowly than the expected...
Authors
David Bickford, Guinevere O.U. Wogan, Deanna H. Olson, K.S. Seshadri, Mark C. Urban, Ana Carnaval, John Measey, Jodi J.L. Rowley, Sean Rovito, Rudolf von May, Susan Walls
The sands of time: Predicting sea level rise impacts to barrier island habitats The sands of time: Predicting sea level rise impacts to barrier island habitats
Coastal beach ecosystems support critical habitat for numerous species and are vulnerable to sea level rise. Sand beaches are spatially and temporally dynamic, making it difficult to accurately predict future habitat loss – estimates that are crucial as species are being assessed for protection. We mapped sand beach habitat on 12 focal barrier islands and low-lying beaches off the Gulf...
Authors
Erin L. Koen, William Barichivich, Susan Walls
Dietary niche of three omnivorous turtle species in a northern Florida river: Insights from stable isotope analysis Dietary niche of three omnivorous turtle species in a northern Florida river: Insights from stable isotope analysis
Macrochelys suwanniensis (Suwannee Alligator Snapping Turtle) coexists with 2 other native large omnivorous turtle species (Chelydra serpentina [Snapping Turtle] and Trachemys scripta scripta [Yellow-bellied Slider]) in a 9-km section of the Santa Fe River in northern Florida. A major shift in dominant submersed aquatic vegetation prompted us to quantify trophic position and niche...
Authors
Mathew Denton, Gerald R. Johnston, Travis M. Thomas, Hardin Waddle, Susan Walls, Kristen Hart
Disentangling direct and indirect effects of extreme events on coastal wetland communities Disentangling direct and indirect effects of extreme events on coastal wetland communities
One of the primary ways in which climate change will impact coastal freshwater wetlands is through changes in the frequency, intensity, timing and distribution of extreme weather events. Disentangling the direct and indirect mechanisms of population- and community-level responses to extreme events is vital to predicting how species composition of coastal wetlands will change under future
Authors
Courtney L. Davis, Susan E. Walls, William J. Barichivich, Mary Brown, David A.W. Miller
Future changes in habitat availability for two specialist snake species in the imperiled rocklands of South Florida, U.S.A. Future changes in habitat availability for two specialist snake species in the imperiled rocklands of South Florida, U.S.A.
Rockland habitat in South Florida, USA, is a threatened ecosystem that has been lost, fragmented, or degraded because of urbanization or other anthropogenic disturbance. Furthermore, low-lying islands and coastal areas are experiencing sea level rise (SLR) and an increased frequency and intensity of tidal flooding, putting rockland habitats there at increasing risk of ecological change...
Authors
Suresh C. Subedi, Susan C. Walls, William Barichivich, Ryan Boyles, Michael S. Ross, J. Aaron Hogan, John A. Tupy