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Brittany Ewing

Brittany Ewing is a Biologist with the U.S. Geological Survey's Western Ecological Research Center.

Science and Products

Pacific pocket mouse in the grass
Pacific pocket mouse
Pacific pocket mouse
Pacific pocket mouse in the grass

Pacific pocket mouse

Pacific pocket mouse

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.

By
Ecosystems, Western Ecological Research Center (WERC)
Pacific pocket mouse in the grass

Pacific pocket mouse

Pacific pocket mouse

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.

By
Ecosystems, Western Ecological Research Center (WERC)

Prioritizing the risk and management of introduced species in a landscape with high indigenous biodiversity

Risk analysis protocols for prioritizing the management of non-native species are numerous, yet few incorporate risk and management in the same analysis or accommodate a broad diversity of taxa outside of a specific geographic area. We adapted a protocol that accounts for these factors to address non-native animal species in the Southern California/Northern Baja California Coast Ecoregion near the
Authors
Jonathan Q. Richmond, Jennifer Kingston, Brittany Ewing, Wendy M Bear, Stacie A. Hathaway, Cedric Lee, Camm C. Swift, Kristine L. Preston, Allison J. Schultz, Barbara E. Kus, Kerwin Russell, Philip Unitt, Bradford D. Hollingsworth, Robert E. Espinoza, Michael Wall, Scott Tremor, Kai Palenscar, Robert N. Fisher
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

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.Methods: We
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)

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) Movement di
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)

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 towards the p
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)

Research to inform Caltrans best management practices for reptile and amphibian road crossings

In October of 2014, the U.S. Geological Survey (USGS) began a 5-year project to conduct research to inform Best Management Practices (BMPs) for amphibian and reptile crossing and barrier systems in California. To inform future conservation and transportation planning, this project involved identification of species at highest risk of negative road impacts, creation of geodatabase and spatial mapp
Authors
Cheryl S. Brehme, Robert N. Fisher, Tom E. S. Langton, Anthony P. Clevenger, Esther Adelsheim, Stephanie Barnes, Tristan Edgarian, Brittany Ewing, Stacie A. Hathaway, Michael Hobbs, Jennifer Kingston, A. Launer, Tritia A. Matsuda, Jeremy B. Sebes, C. Vaughn, Elise Watson
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Science and Products