Cheryl Brehme
Biography
Cheryl has been a biologist with the USGS, Western Ecological Research Center since 2003. She specializes in long-term monitoring programs, conservation ecology and road ecology. She uses current ecological concepts and principles to design, implement, improve, and interpret complex research and monitoring projects for reptiles, amphibians and mammals. In addition to conducting fieldwork for her projects, she models a variety of spatial and demographic population processes and community dynamics in response to habitat change.
Long-Term monitoring
Cheryl has been integral in the design, fieldwork and dynamic occupancy analysis of data for long-term monitoring of endangered species on MCB Camp Pendleton to inform species status and trends and effective habitat and species management actions. These include the arroyo toad (since 2003), Stephens kangaroo rat (since 2005) and Pacific pocket mouse (since 2011).
Road Ecology
Cheryl leads a wide array of research on road ecology, particularly with respect to reptiles and amphibians for the Department of Transportation and other partners. Projects range from assessing risk of road impacts across multiple species, testing the effectiveness of individual components of crossing systems, designing new passages, to conducting wide scale landscape connectivity projects.
American Badger Research
Since 2011, Cheryl has led research studying badger distribution and activity in San Diego County using canine scent detection, badger sign surveys, infrared cameras, facial recognition, hair snags, outreach efforts, and road mortality to document their distribution and core use areas. Future goals include distribution mapping, designing a long-term monitoring program, and employing the use of radiotelemetry to better understand their space use patterns and conservation needs.
Highlighted Publications, Reports and Presentations by Topic
Road Ecology
Brehme CS, S Barnes, JA Tracey, BAI Ewing, C Vaughan ,and RN Fisher. 2020. Movement of Yosemite Toads Along Barrier Fencing and a Novel Elevated Road Segment in Sierra National Forest, CA. 2019. A New Road Crossing Structure for Small Animals: Case study with the Yosemite Toad. Presented at International Conference on Ecology and Transportation, Sacramento, CA Sept 22-26, 2019.
Brehme CS, JA Tracey, BAI Ewing, MJ Hobbs, A Launer, E Adelsheim, and RN Fisher. 2019. Movement of California Tiger Salamanders along barrier fencing and underpasses in Stanford, CA. Poster presented at International Conference on Ecology and Transportation, Sacramento, CA Sept 22-26, 2019.
Brehme, C.S., Hathaway, S.A. and Fisher, R.N., 2018. An objective road risk assessment method for multiple species: ranking 166 reptiles and amphibians in California. Landscape ecology, 33(6), pp.911-935.
Tracey, J. A., C. S. Brehme*, Rochester, C., Clark D., and R. N. Fisher. 2015. The differential use of large underpasses by small animals and effects of adding structure. Presented at 2015 International Conference on Ecology & Transportation, Sep. 20-24, Raleigh, NC.
Tracey, J. A., C. S. Brehme, Rochester, C., Clark D., and R. N. Fisher. 2014. A Field Study of Small Vertebrate Use of Wildlife Underpasses in San Diego County, 2014. U.S. Geological DRAFT Data Summary prepared for California Department of Fish and Wildlife. 74 pp.
Brehme, C.S., Tracey, J.A., Mcclenaghan, L.R. and Fisher, R.N., 2013. Permeability of roads to movement of scrubland lizards and small mammals. Conservation Biology, 27(4), pp.710-720.
Brehme, C.S., 2003. Responses of Small Terrestrial Vertebrates to Roads in Coastal Sage Scrub Ecosystem. MS Thesis, San Diego State University, CA
Long-term Monitoring
Brehme, C.S., Matsuda, T.A., Adsit-Morris, D.T., Clark, D.R., Sebes, J.B., Burlaza, M.A.T. and Fisher, R.N., 2019. Track tube construction and field protocol for small mammal surveys with emphasis on the endangered Pacific pocket mouse (Perognathus longimembris pacificus) (No. 2A15). US Geological Survey.
Fisher, R.N., Brehme, C.S., Hathaway, S.A., Hovey, T.E., Warburton, M.L. and Stokes, D.C., 2018. Longevity and population age structure of the arroyo southwestern toad (Anaxyrus californicus) with drought implications. Ecology and evolution, 8(12), pp.6124-6132.
Mitrovich, M.J., Diffendorfer, J.E., Brehme, C.S. and Fisher, R.N., 2018. Effects of urbanization and habitat composition on site occupancy of two snake species using regional monitoring data from southern California. Global ecology and conservation, 15, p.e00427.
Miller, D.A., Grant, E.H.C., Muths, E., Amburgey, S.M., Adams, M.J., Joseph, M.B., Waddle, J.H., Johnson, P.T., Ryan, M.E., Schmidt, B.R. and Calhoun, D.L…..Fisher, R.N.,…..Brehme, C.S(41 authors)., 2018. Quantifying climate sensitivity and climate-driven change in North American amphibian communities. Nature communications, 9(1), p.3926.
Hobbs, M.T. and Brehme, C.S., 2017. An improved camera trap for amphibians, reptiles, small mammals, and large invertebrates. PloS one, 12(10), p.e0185026.
Matsuda T.A., Brehme, C.S. (co-primary authors), and R.N. Fisher. 2017. MCBCP Arroyo Toad Monitoring Results for 2016 with Trend Analysis from 2003-2016. U.S. Geological Survey Data Summary prepared for Marine Corps Base Camp Pendleton. 65 pp.
Brehme, C.S., D. Adsit-Morris, M. Burlaza, and R.N. Fisher. 2016. Pacific Pocket Mouse Monitoring 2015, MCB, Camp Pendleton. Prepared for AC/S Environmental Security, Marine Corps Base, Camp Pendleton. 53p.
Brehme, C.S., D.R. Clark, and Fisher, R.N. 2016. Stephens’ Kangaroo Rat Monitoring on MCB Camp Pendleton: Results and Trend Analyses for Fall-Winter 2015-16. Report prepared for AC/S Environmental Security, Marine Corps Base, Camp Pendleton. 52pp.
Iwanowicz, D.D., Vandergast, A.G., Cornman, R.S., Adams, C.R., Kohn, J.R., Fisher, R.N. and Brehme, C.S., 2016. Metabarcoding of fecal samples to determine herbivore diets: A case study of the endangered Pacific pocket mouse. PloS one, 11(11), p.e0165366.
Brehme, C.S., Clark, D.R., Rochester, C.J. and Fisher, R.N., 2011. Wildfires alter rodent community structure across four vegetation types in southern California, USA. Fire Ecology, 7(2), pp.81-98.
Matsuda, T., Turschak, G., Brehme, C., Rochester, C., Mitrovich, M. and Fisher, R., 2011. Effects of large-scale wildfires on ground foraging ants (Hymenoptera: Formicidae) in southern California. Environmental Entomology, 40(2), pp.204-216.
Rochester, C.J., Brehme, C.S., Clark, D.R., Stokes, D.C., Hathaway, S.A. and Fisher, R.N., 2010. Reptile and amphibian responses to large-scale wildfires in southern California. Journal of Herpetology, 44(3), pp.333-352.
Brehme, C.S., Boarman, W.I., Hathaway, S.A., Herring, A., Lyren, L., Mendelsohn, M., Pease, K., Rahn, M., Rochester, C., Stokes, D. and Turschak, G., 2009. Spatial and temporal patterns across an ecological boundary: allochthonous effects of a young saltwater lake on a desert ecosystem. Journal of arid environments, 73(9), pp.811-820.
Mendelsohn, M.B., Brehme, C.S., Rochester, C.J., Stokes, D.C., Hathaway, S.A. and Fisher, R.N., 2008. Responses in bird communities to wildland fires in southern California. Fire Ecology, 4(2), pp.63-82.
American Badger Research
Brehme, C.S., M.A. Burlaza, and R.N. Fisher. 2016. Research Results for American Badgers in Western San Diego County, 2015. Data Summary prepared for the San Diego Association of Governments. 27pp.
Brehme, C, D. Adsit-Morris, H. Smith, S. Mondol, S. Wasser, R. Fisher. 2017. The use of Canine Scent Detection, DNA testing and other methods to assess the Distribution of American Badgers in western San Diego County. Presented at 2017 International Urban Ecology Conference, June 4 to 7, San Diego, CA.
Brehme, C. Rempel R*, Smith, H, Mondol S., Wasser, S. and, R. Fisher. 2013. The Use of Canine Scent Detection and DNA Testing to Assess the Distribution of Badgers in Western San Diego County. Poster presented at the International Symposium for Badgers: Biology and Conservation. Edmonton, Alberta, Canada, Oct. 1-3, 2013
Science and Products
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 monitoring plan to assess the status and trends of Pacific pocket mouse and identify important drivers of...
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.
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...
Brehme, Cheryl S.; Tracey, Jeff A.; Ewing, Brittany; Hobbs, Michael J; Launer, Alan E; Matsuda, Tritia; Adelsheim, Esther M. Cole; Fisher, R. N. 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...
Brehme, Cheryl S.; Fisher, R. N.; Langton, Tom E. S.; Clevenger, Anthony P.; Adelsheim, Esther; Barnes, Stephanie; Edgarian, Tristan; Ewing, Brittany; Hathaway, Stacie A.; Hobbs, Michael; Kingston, Jennifer; Launer, A.; Matsuda, Tritia A.; Sebes, Jeremy B.; Vaughn, C.; Watson, Elise
Track tube construction and field protocol for small mammal surveys with emphasis on the endangered Pacific pocket mouse (Perognathus longimembris pacificus)
Track tubes are used to identify small animals by their tracks. Animals that are small enough to fit into the tubes walk over ink pads and onto cardstock paper to obtain bait within the tube, leaving their footprints. The tracking tubes described in this document are designed to be set on the ground with free access and exit at either end with...
Brehme, Cheryl S.; Matsuda, Tritia A.; Adsit-Morris, Devin T.; Clark, Denise R.; Sebes, Jeremy B.; Burlaza, Melanie Anne T.; Fisher, Robert N. 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 >...
Miller, David A.W.; Campbell Grant, Evan H.; Muths, Erin L.; Amburgey, Staci M.; Adams, M.J.; Joseph, Maxwell B.; Waddle, J. Hardin; Johnson, Pieter T.J.; Ryan, Maureen E.; Schmidt, Benedikt R.; Calhoun, Daniel L.; Davis, Courtney L.; Fisher, Robert N.; Green, David M.; Hossack, Blake R.; Rittenhouse, Tracy A.G.; Walls, Susan C.; Bailey, Larissa L.; Cruickshank, Sam S.; Fellers, Gary M.; Gorman, Thomas A.; Haas, Carola A.; Hughson, Ward; Pilliod, David S.; Price, Steven J.; Ray, Andrew M.; Sadinski, Walter; Saenz, Daniel; Barichivich, William J.; Brand, Adrianne B.; Brehme, Cheryl S.; Dagit, Rosi; Delaney, Katy S.; Glorioso, Brad M.; Kats, Lee B.; Kleeman, Patrick M.; Pearl, Christopher; Rochester, Carlton J.; Riley, Seth P. D.; Roth, Mark F.; Sigafus, Brent Effects of urbanization, and habitat composition on site occupancy of two snake species using regional monitoring data from southern California
Detection data from a regional, reptile-monitoring program conducted by the U.S. Geological Survey were analyzed to understand the effects of urbanization and habitat composition on site occupancy of the coachwhip (Masticophis flagellum) and striped racer (M. lateralis) in coastal southern California. Likelihood-based occupancy models indicated...
Mitrovich, Milan J.; Diffendorfer, James E.; Brehme, Cheryl S.; Fisher, Robert N. An objective road risk assessment method for multiple species: ranking 166 reptiles and amphibians in California
ContextTransportation and wildlife agencies may consider the need for barrier structures and safe wildlife road-crossings to maintain the long-term viability of wildlife populations. In order to prioritize these efforts, it is important to identify species that are most at risk of extirpation from road-related impacts.PurposeOur goal was to...
Brehme, Cheryl S.; Hathaway, Stacie A.; Fisher, Robert N. Longevity and population age structure of the arroyo southwestern toad (Anaxyrus californicus) with drought implications
The arroyo southwestern toad is a specialized and federally endangered amphibian endemic to the coastal plains and mountains of central and southern California and northwestern Baja California. It is largely unknown how long these toads live in natural systems, how their population demographics vary across occupied drainages, and how hydrology...
Fisher, Robert N.; Brehme, Cheryl S.; Hathaway, Stacie A.; Hovey, Tim E.; Warburton, Manna L.; Stokes, Drew C. An improved camera trap for amphibians, reptiles, small mammals, and large invertebrates
Camera traps are valuable sampling tools commonly used to inventory and monitor wildlife communities but are challenged to reliably sample small animals. We introduce a novel active camera trap system enabling the reliable and efficient use of wildlife cameras for sampling small animals, particularly reptiles, amphibians, small mammals and large...
Hobbs, Michael T.; Brehme, Cheryl S. Metabarcoding of fecal samples to determine herbivore diets: A case study of the endangered Pacific pocket mouse
Understanding the diet of an endangered species illuminates the animal’s ecology, habitat requirements, and conservation needs. However, direct observation of diet can be difficult, particularly for small, nocturnal animals such as the Pacific pocket mouse (Heteromyidae: Perognathus longimembris pacificus). Very little is known of the dietary...
Iwanowicz, Deborah D.; Vandergast, Amy G.; Cornman, Robert S.; Adams, Cynthia R.; Kohn, Joshua R.; Fisher, Robert N.; Brehme, Cheryl S. Permeability of roads to movement of scrubland lizards and small mammals
A primary objective of road ecology is to understand and predict how roads affect connectivity of wildlife populations. Road avoidance behavior can fragment populations, whereas lack of road avoidance can result in high mortality due to wildlife-vehicle collisions. Many small animal species focus their activities to particular microhabitats within...
Brehme, Cheryl S.; Tracey, Jeff A.; McClenaghan, Leroy R.; Fisher, Robert N. Joint estimation of habitat dynamics and species interactions: Disturbance reduces co-occurrence of non-native predators with an endangered toad
1. Ecologists have long been interested in the processes that determine patterns of species occurrence and co-occurrence. Potential short-comings of many existing empirical approaches that address these questions include a reliance on patterns of occurrence at a single time point, failure to account properly for imperfect detection and treating...
Miller, David A.W.; Brehme, Cheryl S.; Hines, James E.; Nichols, James D.; Fisher, Robert N. Wildfires alter rodent community structure across four vegetation types in southern California, USA
We surveyed burned and unburned plots across four habitat reserves in San Diego County, California, USA, in 2005 and 2006, to assess the effects of the 2003 wildfires on the community structure and relative abundance of rodent species. The reserves each contained multiple vegetation types (coastal sage scrub, chaparral, woodland, and grassland)...
Brehme, Cheryl S.; Clark, Denise R.; Rochester, Carlton J.; Fisher, Robert N.
Research Spotlight: New Study Identifies Effective Under-Road Passage Designs for California Tiger Salamanders
A new study by USGS researchers and partners investigated how California tiger salamanders in Stanford, California interacted with different types of barrier fencing while migrating to their annual breeding site and whether they were able to find and use an under-road tunnel passage system.
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 these animals cross roads safely.
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 crossing structure known as the “toad road” in Sierra National Forest.
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 change has led to a range shift of many wildlife species and thus understanding how these changes in species distribution can be used to predict amphibian community responses that may improve conservation efforts.
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 canorus), this has meant increased mortality from vehicle strikes in addition to other threats from disease, drought, and habitat loss.
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 vulnerability to vehicle strikes and habitat fragmentation from roadways. Their results are published in the journal Landscape Ecology....