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Cheryl Brehme (Former Employee)

Science and Products

A Yosemite toad looks through a mesh fence, holding itself up on its back legs

Reptile and Amphibian Road Ecology

USGS is working with many partners to help reptiles, amphibians and other animals cross roads safely, improving access to essential habitat.
By
Ecosystems Mission Area, Species Management Research Program, Western Ecological Research Center (WERC)
Reptile and Amphibian Road Ecology

Reptile and Amphibian Road Ecology

USGS is working with many partners to help reptiles, amphibians and other animals cross roads safely, improving access to essential habitat.
Learn More
Stephens’ kangaroo rat

Stephens’ Kangaroo Rat Research and Monitoring Program

Western Ecological Research Center (WERC) scientists provide valuable support to management agencies as they work toward recovery of the threatened Stephens’ kangaroo rat (Dipodomys stephensi). The Stephen’s kangaroo rat (SKR) occupies a limited range of habitat within southern California. WERC’s long-term monitoring of SKR at several sites has revealed local trends in distribution and abundance...
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Stephens’ Kangaroo Rat Research and Monitoring Program

Stephens’ Kangaroo Rat Research and Monitoring Program

Western Ecological Research Center (WERC) scientists provide valuable support to management agencies as they work toward recovery of the threatened Stephens’ kangaroo rat (Dipodomys stephensi). The Stephen’s kangaroo rat (SKR) occupies a limited range of habitat within southern California. WERC’s long-term monitoring of SKR at several sites has revealed local trends in distribution and abundance...
Learn More
Pacific pocket mouse

Pacific Pocket Mouse Monitoring and Research Program

Once thought to be extinct, the Pacific pocket mouse ( Perognathus longimembris pacificus) was rediscovered in 1993 and is currently found at three population sites along the southern California coast. USGS researchers and their partners developed a comprehensive long-term research and monitoring plan to assess the status and trends of Pacific pocket mouse and identify important drivers of...
By
Species Management Research Program, Western Ecological Research Center (WERC)
Pacific Pocket Mouse Monitoring and Research Program

Pacific Pocket Mouse Monitoring and Research Program

Once thought to be extinct, the Pacific pocket mouse ( Perognathus longimembris pacificus) was rediscovered in 1993 and is currently found at three population sites along the southern California coast. USGS researchers and their partners developed a comprehensive long-term research and monitoring plan to assess the status and trends of Pacific pocket mouse and identify important drivers of...
Learn More

Species Observations from Pitfall Trap Arrays, Species Pool Matrices, and Patch Locations in Southern California from 1995-2015 Species Observations from Pitfall Trap Arrays, Species Pool Matrices, and Patch Locations in Southern California from 1995-2015

Observations (reduced to detected/not detected) of 45 vertebrate species (seven mammals, seven amphibians, and 31 reptiles) across Southern California pitfall sampling projects conducted between 1995 through 2015. Habitat patch locations of every pitfall sampling project presented in a shapefile. Habitat patches were measured based on the size when pitfall sampling began within each...
By
Western Ecological Research Center (WERC)

Masticophis occupancy in southern California, 1995-2000 Masticophis occupancy in southern California, 1995-2000

These data are CSV files comprised of a heading and tables from Appendix 1 and Appendix 2 in the accompanying paper. The tables show the sampling dates and locations for the coachwhip (Masticophis flagellum) and striped racer (Masticophis lateralis) in pit-fall arrays (Fisher et al. 2008) monitored in southern California from 1995-2000. GPS data are shown in decimal degrees and were...
By
Western Ecological Research Center (WERC)
A Yosemite toad on a road
Yosemite Toad on a Road
Yosemite Toad on a Road
A Yosemite toad on a road

Yosemite Toad on a Road

Yosemite Toad on a Road

A Yosemite toad on a road. Amphibians and reptiles are particularly susceptible to negative effects of roads within their habitat. Many are slow moving, do not avoid roads, and are simply too small for drivers to see and avoid. During rains many amphibians travel long distances regardless of the presence of intersecting roadways.

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
A Yosemite toad on a road

Yosemite Toad on a Road

Yosemite Toad on a Road

A Yosemite toad on a road. Amphibians and reptiles are particularly susceptible to negative effects of roads within their habitat. Many are slow moving, do not avoid roads, and are simply too small for drivers to see and avoid. During rains many amphibians travel long distances regardless of the presence of intersecting roadways.

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Woman looks down at a dog sitting in the grass
Conservation Canine alerts his handler that Pacific pocket mouse scent
Conservation Canine alerts his handler that Pacific pocket mouse scent
Woman looks down at a dog sitting in the grass

Conservation Canine alerts his handler that Pacific pocket mouse scent

Conservation Canine alerts his handler that Pacific pocket mouse scent

Conservation Canine alerts his handler that Pacific pocket mouse scent

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Woman looks down at a dog sitting in the grass

Conservation Canine alerts his handler that Pacific pocket mouse scent

Conservation Canine alerts his handler that Pacific pocket mouse scent

Conservation Canine alerts his handler that Pacific pocket mouse scent

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Mouse standing at the opening of a metal trap
Pacific pocket mouse in Sherman trap
Pacific pocket mouse in Sherman trap
Mouse standing at the opening of a metal trap

Pacific pocket mouse in Sherman trap

Pacific pocket mouse in Sherman trap

Pacific pocket mouse in Sherman trap

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Mouse standing at the opening of a metal trap

Pacific pocket mouse in Sherman trap

Pacific pocket mouse in Sherman trap

Pacific pocket mouse in Sherman trap

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Hand holding a tiny mouse between two fingers
Pacific pocket mouse in hand
Pacific pocket mouse in hand
Hand holding a tiny mouse between two fingers

Pacific pocket mouse in hand

Pacific pocket mouse in hand

Pacific pocket mouse in hand

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Hand holding a tiny mouse between two fingers

Pacific pocket mouse in hand

Pacific pocket mouse in hand

Pacific pocket mouse in hand

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Filter Total Items: 32

Long-term occupancy monitoring reveals value of moderate disturbance for an open-habitat specialist, the Stephens' kangaroo rat (Dipodomys stephensi) Long-term occupancy monitoring reveals value of moderate disturbance for an open-habitat specialist, the Stephens' kangaroo rat (Dipodomys stephensi)

For species of conservation concern, long-term monitoring is vital to properly characterize changes in population distribution and abundance over time. In addition, long-term monitoring guides management decisions by informing and evaluating the efficacy of management actions. A long-term monitoring initiative for the federally threatened Stephens' Kangaroo rat (Dipodomys stephensi, SKR)...
Authors
Cheryl S. Brehme, Philip Robert Gould, Denise Clark, Robert N. Fisher
By
Ecosystems Mission Area, Species Management Research Program, Western Ecological Research Center (WERC)

Interactions among rainfall, fire, forbs and non-native grasses predict occupancy dynamics for the endangered Pacific pocket mouse (Perognathus longimembris pacificus) in a Mediterranean-type ecosystem Interactions among rainfall, fire, forbs and non-native grasses predict occupancy dynamics for the endangered Pacific pocket mouse (Perognathus longimembris pacificus) in a Mediterranean-type ecosystem

It is important to understand species-habitat relationships to implement effective adaptive management for rare species. However, it can be challenging to assess habitat associations and their relationships to abiotic stressors in dynamic habitats without the insights that can be gained from long-term monitoring. We report results from the first six years of extensive track tube...
Authors
Cheryl S. Brehme, Sarah Kay Thomsen, Devin T. Adsit-Morris, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Fecal metabarcoding of the endangered Pacific pocket mouse (Perognathus longimembris pacificus) reveals a diverse and forb rich diet that reflects local habitat availability Fecal metabarcoding of the endangered Pacific pocket mouse (Perognathus longimembris pacificus) reveals a diverse and forb rich diet that reflects local habitat availability

Information on diet breadth and preference can assist in understanding links between food resources and population growth and inform habitat restoration for rare herbivores. We assessed the diet of the endangered Pacific pocket mouse using metabarcoding of fecal samples and compared it to plant community composition in long-term study plots in two populations on Marine Corps Base Camp...
Authors
A.G. Vandergast, Cheryl S. Brehme, Deborah Iwanowicz, Robert S. Cornman, Devin T. Adsit-Morris, Robert N. Fisher
By
Ecosystems Mission Area, Eastern Ecological Science Center, Western Ecological Research Center (WERC)

Interstate 15 wildlife crossing design considerations for focal wildlife species - Santa Ana-Palomar Mountains Linkage southern California Interstate 15 wildlife crossing design considerations for focal wildlife species - Santa Ana-Palomar Mountains Linkage southern California

The Nature Conservancy (TNC) and the California Department of Transportation (Caltrans), along with landowners including San Diego State University, California Department of Fish and Wildlife, Western Riverside Regional Conservation Authority and Riverside County Flood Control District are developing wildlife crossing infrastructure projects along a 3-mile stretch of Interstate 15 (I-15)...
Authors
Trish Smith, Cheryl S. Brehme, Jill Carpenter, Nancy A. Frost, Megan Jennings, Barbara E. Kus, Scott Quinnell, Spring Straham, T. Winston Vickers
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Elevated road segment (ERS) passage design may provide enhanced connectivity for amphibians, reptiles, and small mammals Elevated road segment (ERS) passage design may provide enhanced connectivity for amphibians, reptiles, and small mammals

Introduction: Designs for safe and effective road crossing structures for small animals are typically under-road microtunnels and culverts which have varying levels of effectiveness reported in the scientific literature. Many species, particularly migratory amphibians, may have limited ability to find and use passages if they are too far apart, resulting in substantial barrier effects...
Authors
Cheryl S. Brehme, Stephanie Barnes, Brittany Ewing, Philip Robert Gould, Cassie Vaughan, Michael Hobbs, Charles Tornaci, Sarah Holm, Hanna Sheldon, Jon Fiutak, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Internal structural cover and ledges facilitate the use of large underpasses by multiple wildlife species and groups Internal structural cover and ledges facilitate the use of large underpasses by multiple wildlife species and groups

No abstract available.
Authors
Cheryl S. Brehme, Jeff A. Tracey, Philip Robert Gould, Carlton J. Rochester, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Quantitative SWOT analysis: A structured and collaborative approach to reintroduction site selection for the endangered Pacific pocket mouse Quantitative SWOT analysis: A structured and collaborative approach to reintroduction site selection for the endangered Pacific pocket mouse

Species extinction and loss of biodiversity are major crises in the Anthropocene. Translocations of threatened and endangered species, the movement of individuals to augment existing or establish new populations, are increasingly important conservation tools, but have historically had limited success. Selection of a suitable receiver site is essential to translocation success, with poor...
Authors
Rachel Y. Chock, William B Miller, Shauna N D King, Cheryl S. Brehme, Robert N. Fisher, Hans Sin, Peggy Wilcox, Jill Terp, Scott Tremor, Matthew R Major, Korie Merrill, Wayne D Spencer, Sherri Sullivan, Deborah M Shier
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Research to inform passage spacing for migratory amphibians and to evaluate efficacy and designs for open elevated road segment (ERS) passages Research to inform passage spacing for migratory amphibians and to evaluate efficacy and designs for open elevated road segment (ERS) passages

This is a multifaceted project that includes three main areas of research targeted to inform effective crossing systems for migratory amphibians, a large group of species which are at very high risk from negative impacts from roads within their habitats (Glista et al. 2008, Hamer and McDonnell 2008, Semlitsch 2008, Brehme et al. 2018). The three projects presented in this report are:1)...
Authors
Cheryl S. Brehme, Stephanie Barnes, Brittany Ewing, Cassie Vaughan, Michael Hobbs, Charles Tornaci, Philip Robert Gould, Sarah Holm, Hanna Sheldon, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Range-wide persistence of the endangered arroyo toad (Anaxyrus californicus) for 20+ years following a prolonged drought Range-wide persistence of the endangered arroyo toad (Anaxyrus californicus) for 20+ years following a prolonged drought

Prolonged drought due to climate change has negatively impacted amphibians in southern California, U.S.A. Due to the severity and length of the current drought, agencies and researchers had growing concern for the persistence of the arroyo toad (Anaxyrus californicus), an endangered endemic amphibian in this region. Range-wide surveys for this species had not been conducted for at least...
Authors
Cynthia Joan Hitchcock, Elizabeth Gallegos, Adam R. Backlin, Russell Barabe, Peter H. Bloom, Kimberly Boss, Cheryl S. Brehme, Christopher W. Brown, Denise Clark, Elizabeth R. Clark, Kevin Cooper, Julie Donnell, Edward L Ervin, Peter Famolaro, Kim M. Guilliam, Jaquelyn Hancock, Nicholas Hess, Steven Howard, Valerie Hubbartt, Patrick Lieske, Robert E. Lovich, Tritia Matsuda, Katherin Meyer-Wilkins, Kamarul Muri, Barry Nerhus, Jeffrey A. Nordland, Brock Ortega, Robert Packard, Ruben Ramirez, Sam C. IV Stewart, Samuel Sweet, Manna L. Warburton, Jeffrey Wells, Ryan Winkleman, Kirsten Winter, Brian Zitt, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Impacts of a non-indigenous ecosystem engineer, the American beaver (Castor canadensis), in a biodiversity hotspot Impacts of a non-indigenous ecosystem engineer, the American beaver (Castor canadensis), in a biodiversity hotspot

Non-native species having high per capita impacts in invaded communities are those that modulate resource availability and alter disturbance regimes in ways that are biologically incompatible with the native biota. In areas where it has been introduced by humans, American beaver (Castor canadensis) is an iconic example of such species due to its capacity to alter trophic dynamics of...
Authors
Jonathan Q. Richmond, Camm C. Swift, Thomas A. Wake, Cheryl S. Brehme, Kristine L. Preston, Barbara E. Kus, Edward L Ervin, Scott Tremor, Tritia Matsuda, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Responses of migratory amphibians to barrier fencing inform the spacing of road underpasses: A case study with California tiger salamanders (Ambystoma californiense) in Stanford, CA, USA Responses of migratory amphibians to barrier fencing inform the spacing of road underpasses: A case study with California tiger salamanders (Ambystoma californiense) in Stanford, CA, USA

Migratory amphibians are at high risk of negative impacts when roads intersect their upland and breeding habitats. Road mortality can reduce population abundance, survivorship, breeding, recruitment, and probability of long-term persistence. Increasingly, environmental planners recommend installation of under-road tunnels with barrier fencing to reduce mortality and direct amphibians...
Authors
Cheryl S. Brehme, Jeff A. Tracey, Brittany Ewing, Michael J. Hobbs, Alan E. Launer, Tritia Matsuda, Esther M. Cole Adelsheim, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Predictability of invasive Argentine ant distribution across Mediterranean ecoregions of southern California Predictability of invasive Argentine ant distribution across Mediterranean ecoregions of southern California

The invasiveness of nonnative taxa can vary across a landscape due to environmental gradients, suggesting that location-dependent management strategies may be more effective at reducing spread compared to a “one size fits all” approach across the entire introduced range. Using bait stations placed along linear transects within habitat preserves, we tested for effects of ecoregion...
Authors
Jonathan Q. Richmond, Tritia Matsuda, Cheryl S. Brehme, Emily E. Perkins, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Animal Crossing: New Research Guides Efforts to Protect California’s Amphibians and Reptiles from Road Danger

Animal Crossing: New Research Guides Efforts to Protect California’s Amphibians and Reptiles from Road Danger

Roads can be dangerous for California’s reptiles and amphibians, but a five-year study and new video show that there are effective strategies to help...

Read Article
Caught on Camera: Sierra Martens and Flying Squirrels Using Wildlife Passage

Caught on Camera: Sierra Martens and Flying Squirrels Using Wildlife Passage

The adorable Sierra Marten pictured below was caught on wildlife camera in October. The camera was set up to study animal movement under a new road...

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

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...

Read Article
Toad Crossing Ahead: New Study Tests Elevated Roads as Underpasses for Rare Toad

Toad Crossing Ahead: New Study Tests Elevated Roads as Underpasses for Rare Toad

Many amphibians are either too small or too slow to avoid an oncoming car. For some populations of the Federally threatened Yosemite toad (Anaxyrus...

Read Article
New USGS Study Paves a Path Forward for Reptiles, Amphibians, and Roadways

New USGS Study Paves a Path Forward for Reptiles, Amphibians, and Roadways

In a new study, U.S. Geological Survey (USGS) scientists ranked more than 160 species and sub-species of reptiles and amphibians in terms of their...

Read Article
Paved Roadways Can Disrupt Movement of Small Wildlife

Paved Roadways Can Disrupt Movement of Small Wildlife

When does the pocket mouse cross the road? If the road is paved, it may not. As evidenced by many a roadkill carcass, high traffic roads pose an...

Read Article

Science and Products

A Yosemite toad looks through a mesh fence, holding itself up on its back legs

Reptile and Amphibian Road Ecology

USGS is working with many partners to help reptiles, amphibians and other animals cross roads safely, improving access to essential habitat.
By
Ecosystems Mission Area, Species Management Research Program, Western Ecological Research Center (WERC)
Reptile and Amphibian Road Ecology

Reptile and Amphibian Road Ecology

USGS is working with many partners to help reptiles, amphibians and other animals cross roads safely, improving access to essential habitat.
Learn More
Stephens’ kangaroo rat

Stephens’ Kangaroo Rat Research and Monitoring Program

Western Ecological Research Center (WERC) scientists provide valuable support to management agencies as they work toward recovery of the threatened Stephens’ kangaroo rat (Dipodomys stephensi). The Stephen’s kangaroo rat (SKR) occupies a limited range of habitat within southern California. WERC’s long-term monitoring of SKR at several sites has revealed local trends in distribution and abundance...
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Stephens’ Kangaroo Rat Research and Monitoring Program

Stephens’ Kangaroo Rat Research and Monitoring Program

Western Ecological Research Center (WERC) scientists provide valuable support to management agencies as they work toward recovery of the threatened Stephens’ kangaroo rat (Dipodomys stephensi). The Stephen’s kangaroo rat (SKR) occupies a limited range of habitat within southern California. WERC’s long-term monitoring of SKR at several sites has revealed local trends in distribution and abundance...
Learn More
Pacific pocket mouse

Pacific Pocket Mouse Monitoring and Research Program

Once thought to be extinct, the Pacific pocket mouse ( Perognathus longimembris pacificus) was rediscovered in 1993 and is currently found at three population sites along the southern California coast. USGS researchers and their partners developed a comprehensive long-term research and monitoring plan to assess the status and trends of Pacific pocket mouse and identify important drivers of...
By
Species Management Research Program, Western Ecological Research Center (WERC)
Pacific Pocket Mouse Monitoring and Research Program

Pacific Pocket Mouse Monitoring and Research Program

Once thought to be extinct, the Pacific pocket mouse ( Perognathus longimembris pacificus) was rediscovered in 1993 and is currently found at three population sites along the southern California coast. USGS researchers and their partners developed a comprehensive long-term research and monitoring plan to assess the status and trends of Pacific pocket mouse and identify important drivers of...
Learn More

Species Observations from Pitfall Trap Arrays, Species Pool Matrices, and Patch Locations in Southern California from 1995-2015 Species Observations from Pitfall Trap Arrays, Species Pool Matrices, and Patch Locations in Southern California from 1995-2015

Observations (reduced to detected/not detected) of 45 vertebrate species (seven mammals, seven amphibians, and 31 reptiles) across Southern California pitfall sampling projects conducted between 1995 through 2015. Habitat patch locations of every pitfall sampling project presented in a shapefile. Habitat patches were measured based on the size when pitfall sampling began within each...
By
Western Ecological Research Center (WERC)

Masticophis occupancy in southern California, 1995-2000 Masticophis occupancy in southern California, 1995-2000

These data are CSV files comprised of a heading and tables from Appendix 1 and Appendix 2 in the accompanying paper. The tables show the sampling dates and locations for the coachwhip (Masticophis flagellum) and striped racer (Masticophis lateralis) in pit-fall arrays (Fisher et al. 2008) monitored in southern California from 1995-2000. GPS data are shown in decimal degrees and were...
By
Western Ecological Research Center (WERC)
A Yosemite toad on a road
Yosemite Toad on a Road
Yosemite Toad on a Road
A Yosemite toad on a road

Yosemite Toad on a Road

Yosemite Toad on a Road

A Yosemite toad on a road. Amphibians and reptiles are particularly susceptible to negative effects of roads within their habitat. Many are slow moving, do not avoid roads, and are simply too small for drivers to see and avoid. During rains many amphibians travel long distances regardless of the presence of intersecting roadways.

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
A Yosemite toad on a road

Yosemite Toad on a Road

Yosemite Toad on a Road

A Yosemite toad on a road. Amphibians and reptiles are particularly susceptible to negative effects of roads within their habitat. Many are slow moving, do not avoid roads, and are simply too small for drivers to see and avoid. During rains many amphibians travel long distances regardless of the presence of intersecting roadways.

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Woman looks down at a dog sitting in the grass
Conservation Canine alerts his handler that Pacific pocket mouse scent
Conservation Canine alerts his handler that Pacific pocket mouse scent
Woman looks down at a dog sitting in the grass

Conservation Canine alerts his handler that Pacific pocket mouse scent

Conservation Canine alerts his handler that Pacific pocket mouse scent

Conservation Canine alerts his handler that Pacific pocket mouse scent

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Woman looks down at a dog sitting in the grass

Conservation Canine alerts his handler that Pacific pocket mouse scent

Conservation Canine alerts his handler that Pacific pocket mouse scent

Conservation Canine alerts his handler that Pacific pocket mouse scent

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Mouse standing at the opening of a metal trap
Pacific pocket mouse in Sherman trap
Pacific pocket mouse in Sherman trap
Mouse standing at the opening of a metal trap

Pacific pocket mouse in Sherman trap

Pacific pocket mouse in Sherman trap

Pacific pocket mouse in Sherman trap

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Mouse standing at the opening of a metal trap

Pacific pocket mouse in Sherman trap

Pacific pocket mouse in Sherman trap

Pacific pocket mouse in Sherman trap

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Hand holding a tiny mouse between two fingers
Pacific pocket mouse in hand
Pacific pocket mouse in hand
Hand holding a tiny mouse between two fingers

Pacific pocket mouse in hand

Pacific pocket mouse in hand

Pacific pocket mouse in hand

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Hand holding a tiny mouse between two fingers

Pacific pocket mouse in hand

Pacific pocket mouse in hand

Pacific pocket mouse in hand

By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Filter Total Items: 32

Long-term occupancy monitoring reveals value of moderate disturbance for an open-habitat specialist, the Stephens' kangaroo rat (Dipodomys stephensi) Long-term occupancy monitoring reveals value of moderate disturbance for an open-habitat specialist, the Stephens' kangaroo rat (Dipodomys stephensi)

For species of conservation concern, long-term monitoring is vital to properly characterize changes in population distribution and abundance over time. In addition, long-term monitoring guides management decisions by informing and evaluating the efficacy of management actions. A long-term monitoring initiative for the federally threatened Stephens' Kangaroo rat (Dipodomys stephensi, SKR)...
Authors
Cheryl S. Brehme, Philip Robert Gould, Denise Clark, Robert N. Fisher
By
Ecosystems Mission Area, Species Management Research Program, Western Ecological Research Center (WERC)

Interactions among rainfall, fire, forbs and non-native grasses predict occupancy dynamics for the endangered Pacific pocket mouse (Perognathus longimembris pacificus) in a Mediterranean-type ecosystem Interactions among rainfall, fire, forbs and non-native grasses predict occupancy dynamics for the endangered Pacific pocket mouse (Perognathus longimembris pacificus) in a Mediterranean-type ecosystem

It is important to understand species-habitat relationships to implement effective adaptive management for rare species. However, it can be challenging to assess habitat associations and their relationships to abiotic stressors in dynamic habitats without the insights that can be gained from long-term monitoring. We report results from the first six years of extensive track tube...
Authors
Cheryl S. Brehme, Sarah Kay Thomsen, Devin T. Adsit-Morris, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Fecal metabarcoding of the endangered Pacific pocket mouse (Perognathus longimembris pacificus) reveals a diverse and forb rich diet that reflects local habitat availability Fecal metabarcoding of the endangered Pacific pocket mouse (Perognathus longimembris pacificus) reveals a diverse and forb rich diet that reflects local habitat availability

Information on diet breadth and preference can assist in understanding links between food resources and population growth and inform habitat restoration for rare herbivores. We assessed the diet of the endangered Pacific pocket mouse using metabarcoding of fecal samples and compared it to plant community composition in long-term study plots in two populations on Marine Corps Base Camp...
Authors
A.G. Vandergast, Cheryl S. Brehme, Deborah Iwanowicz, Robert S. Cornman, Devin T. Adsit-Morris, Robert N. Fisher
By
Ecosystems Mission Area, Eastern Ecological Science Center, Western Ecological Research Center (WERC)

Interstate 15 wildlife crossing design considerations for focal wildlife species - Santa Ana-Palomar Mountains Linkage southern California Interstate 15 wildlife crossing design considerations for focal wildlife species - Santa Ana-Palomar Mountains Linkage southern California

The Nature Conservancy (TNC) and the California Department of Transportation (Caltrans), along with landowners including San Diego State University, California Department of Fish and Wildlife, Western Riverside Regional Conservation Authority and Riverside County Flood Control District are developing wildlife crossing infrastructure projects along a 3-mile stretch of Interstate 15 (I-15)...
Authors
Trish Smith, Cheryl S. Brehme, Jill Carpenter, Nancy A. Frost, Megan Jennings, Barbara E. Kus, Scott Quinnell, Spring Straham, T. Winston Vickers
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Elevated road segment (ERS) passage design may provide enhanced connectivity for amphibians, reptiles, and small mammals Elevated road segment (ERS) passage design may provide enhanced connectivity for amphibians, reptiles, and small mammals

Introduction: Designs for safe and effective road crossing structures for small animals are typically under-road microtunnels and culverts which have varying levels of effectiveness reported in the scientific literature. Many species, particularly migratory amphibians, may have limited ability to find and use passages if they are too far apart, resulting in substantial barrier effects...
Authors
Cheryl S. Brehme, Stephanie Barnes, Brittany Ewing, Philip Robert Gould, Cassie Vaughan, Michael Hobbs, Charles Tornaci, Sarah Holm, Hanna Sheldon, Jon Fiutak, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Internal structural cover and ledges facilitate the use of large underpasses by multiple wildlife species and groups Internal structural cover and ledges facilitate the use of large underpasses by multiple wildlife species and groups

No abstract available.
Authors
Cheryl S. Brehme, Jeff A. Tracey, Philip Robert Gould, Carlton J. Rochester, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Quantitative SWOT analysis: A structured and collaborative approach to reintroduction site selection for the endangered Pacific pocket mouse Quantitative SWOT analysis: A structured and collaborative approach to reintroduction site selection for the endangered Pacific pocket mouse

Species extinction and loss of biodiversity are major crises in the Anthropocene. Translocations of threatened and endangered species, the movement of individuals to augment existing or establish new populations, are increasingly important conservation tools, but have historically had limited success. Selection of a suitable receiver site is essential to translocation success, with poor...
Authors
Rachel Y. Chock, William B Miller, Shauna N D King, Cheryl S. Brehme, Robert N. Fisher, Hans Sin, Peggy Wilcox, Jill Terp, Scott Tremor, Matthew R Major, Korie Merrill, Wayne D Spencer, Sherri Sullivan, Deborah M Shier
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Research to inform passage spacing for migratory amphibians and to evaluate efficacy and designs for open elevated road segment (ERS) passages Research to inform passage spacing for migratory amphibians and to evaluate efficacy and designs for open elevated road segment (ERS) passages

This is a multifaceted project that includes three main areas of research targeted to inform effective crossing systems for migratory amphibians, a large group of species which are at very high risk from negative impacts from roads within their habitats (Glista et al. 2008, Hamer and McDonnell 2008, Semlitsch 2008, Brehme et al. 2018). The three projects presented in this report are:1)...
Authors
Cheryl S. Brehme, Stephanie Barnes, Brittany Ewing, Cassie Vaughan, Michael Hobbs, Charles Tornaci, Philip Robert Gould, Sarah Holm, Hanna Sheldon, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Range-wide persistence of the endangered arroyo toad (Anaxyrus californicus) for 20+ years following a prolonged drought Range-wide persistence of the endangered arroyo toad (Anaxyrus californicus) for 20+ years following a prolonged drought

Prolonged drought due to climate change has negatively impacted amphibians in southern California, U.S.A. Due to the severity and length of the current drought, agencies and researchers had growing concern for the persistence of the arroyo toad (Anaxyrus californicus), an endangered endemic amphibian in this region. Range-wide surveys for this species had not been conducted for at least...
Authors
Cynthia Joan Hitchcock, Elizabeth Gallegos, Adam R. Backlin, Russell Barabe, Peter H. Bloom, Kimberly Boss, Cheryl S. Brehme, Christopher W. Brown, Denise Clark, Elizabeth R. Clark, Kevin Cooper, Julie Donnell, Edward L Ervin, Peter Famolaro, Kim M. Guilliam, Jaquelyn Hancock, Nicholas Hess, Steven Howard, Valerie Hubbartt, Patrick Lieske, Robert E. Lovich, Tritia Matsuda, Katherin Meyer-Wilkins, Kamarul Muri, Barry Nerhus, Jeffrey A. Nordland, Brock Ortega, Robert Packard, Ruben Ramirez, Sam C. IV Stewart, Samuel Sweet, Manna L. Warburton, Jeffrey Wells, Ryan Winkleman, Kirsten Winter, Brian Zitt, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Impacts of a non-indigenous ecosystem engineer, the American beaver (Castor canadensis), in a biodiversity hotspot Impacts of a non-indigenous ecosystem engineer, the American beaver (Castor canadensis), in a biodiversity hotspot

Non-native species having high per capita impacts in invaded communities are those that modulate resource availability and alter disturbance regimes in ways that are biologically incompatible with the native biota. In areas where it has been introduced by humans, American beaver (Castor canadensis) is an iconic example of such species due to its capacity to alter trophic dynamics of...
Authors
Jonathan Q. Richmond, Camm C. Swift, Thomas A. Wake, Cheryl S. Brehme, Kristine L. Preston, Barbara E. Kus, Edward L Ervin, Scott Tremor, Tritia Matsuda, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Responses of migratory amphibians to barrier fencing inform the spacing of road underpasses: A case study with California tiger salamanders (Ambystoma californiense) in Stanford, CA, USA Responses of migratory amphibians to barrier fencing inform the spacing of road underpasses: A case study with California tiger salamanders (Ambystoma californiense) in Stanford, CA, USA

Migratory amphibians are at high risk of negative impacts when roads intersect their upland and breeding habitats. Road mortality can reduce population abundance, survivorship, breeding, recruitment, and probability of long-term persistence. Increasingly, environmental planners recommend installation of under-road tunnels with barrier fencing to reduce mortality and direct amphibians...
Authors
Cheryl S. Brehme, Jeff A. Tracey, Brittany Ewing, Michael J. Hobbs, Alan E. Launer, Tritia Matsuda, Esther M. Cole Adelsheim, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Predictability of invasive Argentine ant distribution across Mediterranean ecoregions of southern California Predictability of invasive Argentine ant distribution across Mediterranean ecoregions of southern California

The invasiveness of nonnative taxa can vary across a landscape due to environmental gradients, suggesting that location-dependent management strategies may be more effective at reducing spread compared to a “one size fits all” approach across the entire introduced range. Using bait stations placed along linear transects within habitat preserves, we tested for effects of ecoregion...
Authors
Jonathan Q. Richmond, Tritia Matsuda, Cheryl S. Brehme, Emily E. Perkins, Robert N. Fisher
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
Animal Crossing: New Research Guides Efforts to Protect California’s Amphibians and Reptiles from Road Danger

Animal Crossing: New Research Guides Efforts to Protect California’s Amphibians and Reptiles from Road Danger

Roads can be dangerous for California’s reptiles and amphibians, but a five-year study and new video show that there are effective strategies to help...

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Caught on Camera: Sierra Martens and Flying Squirrels Using Wildlife Passage

Caught on Camera: Sierra Martens and Flying Squirrels Using Wildlife Passage

The adorable Sierra Marten pictured below was caught on wildlife camera in October. The camera was set up to study animal movement under a new road...

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

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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Toad Crossing Ahead: New Study Tests Elevated Roads as Underpasses for Rare Toad

Toad Crossing Ahead: New Study Tests Elevated Roads as Underpasses for Rare Toad

Many amphibians are either too small or too slow to avoid an oncoming car. For some populations of the Federally threatened Yosemite toad (Anaxyrus...

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New USGS Study Paves a Path Forward for Reptiles, Amphibians, and Roadways

New USGS Study Paves a Path Forward for Reptiles, Amphibians, and Roadways

In a new study, U.S. Geological Survey (USGS) scientists ranked more than 160 species and sub-species of reptiles and amphibians in terms of their...

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Paved Roadways Can Disrupt Movement of Small Wildlife

Paved Roadways Can Disrupt Movement of Small Wildlife

When does the pocket mouse cross the road? If the road is paved, it may not. As evidenced by many a roadkill carcass, high traffic roads pose an...

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