Western Ecological Research Center
Publications
Below is a list of WERC's peer-reviewed publications. If you are searching for a specific publication and cannot find it in this list, please contact werc_web@usgs.gov
Development of demographic models to analyze populations with multi-year data—Using Agassiz’s Desert Tortoise (Gopherus agassizii) as a case study
We developed a model for analyzing multi-year demographic data for long-lived animals and used data from a population of Agassiz’s desert tortoise (Gopherus agassizii) at the Desert Tortoise Research Natural Area in the western Mojave Desert of California as a case study. The study area was 7.77 square kilometers and included two locations: inside...
Berry, Kristin H.; Yee, Julie L.
Distribution and abundance of Southwestern Willow Flycatchers (Empidonax traillii extimus) on the upper San Luis Rey River, San Diego County, California—2020 data summary
We surveyed for Southwestern Willow Flycatchers (Empidonax traillii extimus; flycatcher) along the upper San Luis Rey River, near Lake Henshaw, in Santa Ysabel, California, in 2020. Surveys were completed at four locations: three downstream from Lake Henshaw, where nest monitoring occurred from 2015 to 2019 (Rey River Ranch [RRR], Cleveland...
Howell, Scarlett L.; Kus, Barbara E.
An integrated population model for southern sea otters
Southern sea otters (Enhydra lutris nereis) have recovered slowly from their near extinction a century ago, and their continued recovery has been challenged by multiple natural and anthropogenic factors. Development of an integrated population model (IPM) for southern sea otters has been identified as a management priority, to help in evaluating...
Tinker, M. Tim; Carswell, Lilian P.; Tomoleoni, Joseph A.; Hatfield, Brian B.; Harris, Michael D.; Miller, Melissa A.; Moriarty, Megan E.; Johnson, Christine K.; Young, Colleen; Henkel, Laird A.; Staedler, Michelle M.; Miles, A. Keith; Yee, Julie L.
Integrating telemetry data at several scales with spatial capture–recapture to improve density estimates
Accurate population estimates are essential for monitoring and managing wildlife populations. Mark–recapture sampling methods have regularly been used to estimate population parameters for rare and cryptic species, including the federally listed Mojave desert tortoise (Gopherus agassizii); however, the methods employed are often plagued by...
Mitchell, Corey I; Shoemaker, Kevin T.; Esque, Todd C.; Vandergast, A. G.; Hromada, Steven J.; Dutcher, Kirsten E.; Heaton, Jill S.; Nussear, Kenneth E. Informing wetland management with waterfowl movement and sanctuary use responses to human-induced disturbance
Long-term environmental management to prevent waterfowl population declines is informed by ecology, movement behavior and habitat use patterns. Extrinsic factors, such as human-induced disturbance, can cause behavioral changes which may influence movement and resource needs, driving variation that affects management efficacy. To better...
McDuie, Fiona; Lorenz, Austen; Klinger, Robert C.; Overton, Cory T.; Feldheim, Cliff L.; Ackerman, Joshua T.; Casazza, Michael L. Sage-grouse population dynamics are adversely impacted by overabundant feral horses
In recent decades, feral horse (Equus caballus; horse) populations increased in sagebrush (Artimesia spp.) ecosystems, especially within the Great Basin, to the point of exceeding maximum appropriate management levels (AMLmax), which were set by land administrators to balance resource use by feral horses, livestock, and wildlife....
Coates, Peter S.; O'Neil, Shawn; Munoz, Diana A.; Dwight, Ian; Tull, John C. Ignitions explain more than climate or weather in driving Santa Ana Wind fires
Autumn and winter Santa Ana wind (SAW)–driven wildfires play a substantial role in area burned and societal losses in southern California. Temperature during the event and antecedent precipitation in the week or month prior play a minor role in determining area burned. Burning is dependent on wind intensity and number of human-ignited fires. Over...
Keeley, Jon; Guzman-Morales, Janin; Gershunov, Alexander; Syphard, Alexandra D.; Cayan, Daniel; Pierce, David W; Flannigan, Michael; Brown, Tim J Conservation implications of spatiotemporal variation in the terrestrial ecology of Western spadefoots
Conservation of species reliant on ephemeral resources can be especially challenging in the face of a changing climate. Western spadefoots (Spea hammondii) are small burrowing anurans that breed in ephemeral pools, but adults spend the majority of their lives underground in adjacent terrestrial habitat. Western spadefoots are of conservation...
Halstead, Brian J.; Baumberger, Katherine L.; Backlin, Adam R.; Kleeman, Patrick M.; Wong, Monique Nicole; Gallegos, Elizabeth; Rose, Jonathan P.; Fisher, Robert N.
Climate change vulnerability assessment for the California coastal national monument—Trinidad and Point Arena-Stornetta units
Executive SummaryThe California Coastal National Monument protects islets, reefs, and rock outcropping habitats in six onshore units, including the Trinidad and Point Arena-Stornetta Units.The California Coastal National Monument provides crucial habitat for resident and migratory species of seabirds, marine mammals, and invertebrates, which...
Thorne, Karen M.; Freeman, Chase M.; Buffington, Kevin J.; De La Cruz, Susan E.W. Effects of season, location, species, and sex on hematologic and plasma biochemical values and body mass in free-ranging Grebes (Aechmophorus species)
The effects of season, location, species, and sex on body weight and a comprehensive array of blood chemistry and hematology analytes were compared for free-ranging western (Aechmophorus occidentalis) and Clark's (Aechmophorus clarkii) grebes. Birds (n = 56) were collected from Puget Sound, WA, and Monterey Bay and San Francisco Bay, CA, from...
Anderson, Nancy L; De La Cruz, Susan E. W.; Gaydos, Joseph K; Ziccardi, Michael H.; Harvey, Danielle J
Least Bell's Vireos and Southwestern Willow Flycatchers at the San Luis Rey flood risk management project area in San Diego County, California—Breeding activities and habitat use—2020 annual report
Executive SummarySurveys and monitoring for the endangered Least Bell’s Vireo (Vireo bellii pusillus; vireo) were done at the San Luis Rey Flood Risk Management Project Area (Project Area) in the city of Oceanside, San Diego County, California, between March 31 and July 20, 2020. We completed four protocol surveys during the breeding season,...
Houston, Alexandra; Allen, Lisa D.; Pottinger, Ryan E.; Kus, Barbara E. A tale of two valleys: Endangered species policy and the fate of the giant gartersnake
By the mid-20th Century, giant gartersnakes (Thamnophis gigas) had lost more than 90% of their Central Valley marsh habitat and were extirpated from more than two-thirds of their range. This massive habitat loss led to their inclusion in the inaugural list of rare species under the California Endangered Species Act (CESA). Listing under the CESA...
Halstead, Brian J.; Valcarcel, Patricia; Kim, Richard; Jordan, Anna; Rose, Jonathan P.; Skalos, Shannon; Reyes, Gabriel; Ersan, Julia; Casazza, Michael L.; Essert, Allison; Fulton, Alexandria M