Western Ecological Research Center
Assessing effects of nonnative crayfish on mosquito survival
Introductions of nonnative predators often reduce biodiversity and affect natural predator–prey relationships and may increase the abundance of potential disease vectors (e.g., mosquitoes) indirectly through competition or predation cascades. The Santa Monica Mountains (California, U.S.A.), situated in a global biodiversity hotspot, is an area of...Bucciarelli, Gary M.; Suh, Daniel; Davis Lamb, Avery; Roberts, Dave; Sharpton, Debra; Shaffer, H. Bradley; Fisher, Robert N.; Kats, Lee B.
Modeling resource selection of bobcats (Lynx rufus) and vertebrate species distributions in Orange County, southern California
For nature reserves in urban settings, wildlife and wildlife habitats may be affected by recreational activities and intensive, adjacent development. Sustaining biodiversity in such reserves is a challenge for land and natural resource managers, but identification of core areas and key resources for wildlife species may help in planning for...Boydston, Erin E.; Tracey, Jeff A.
Spatial decision‐support tools to guide restoration and seed‐sourcing in the Desert Southwest
Altered disturbance regimes and shifting climates have increased the need for large‐scale restoration treatments across the western United States. Seed‐sourcing remains a considerable challenge for revegetation efforts, particularly on public lands where policy favors the use of native, locally sourced plant material to avoid maladaptation. An...Shryock, Daniel F.; DeFalco, Lesley A.; Esque, Todd C.
California Gull population growth and ecological impacts in the San Francisco Bay estuary, 1980–2016
The breeding population of California Gulls (Larus californicus) in the San Francisco Bay estuary increased from 24 individuals in 1980 to a peak of over 53,000 in 2014, then declined to 38,040 in 2016. The expansion of the breeding population may be related to the availability of suitable nesting sites in close proximity to anthropogenic food...Burns, Catherine E.; Ackerman, Joshua T.; Washburn, Natalie B.; Bluso-Demers, Jill; Robinson-Nilsen, Caitlin; Strong, Cheryl
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, Michael 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; 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
Drivers of chaparral type conversion to herbaceous vegetation in coastal Southern California
AimIn Southern California, native woody shrublands known as chaparral support exceptional biodiversity. However, large‐scale conversion of chaparral into largely exotic herbaceous cover is a major ecological threat and serious conservation concern. Due to substantial uncertainty regarding the causes and extent of this vegetation change, we aimed...Syphard, Alexandra D.; Brennan, Teresa J.; Keeley, Jon E.
California sea otter (Enhydra lutris nereis) census results, spring 2018
The 2018 census of southern sea otters (Enhydra lutris nereis) was conducted from late April to mid-May along the mainland coast of central California and in April at San Nicolas Island in southern California. The 3-year average of combined counts from the mainland range and San Nicolas Island was 3,128, a decrease of 58 sea otters from the...Hatfield, Brian B.; Yee, Julie L.; Kenner, Michael C.; Tomoleoni, Joseph A.; Tinker, M. Tim
Toward salt marsh harvest mouse recovery: A review
The salt marsh harvest mouse (SMHM, Reithrodontomys raviventris) is an endangered species, endemic to the San Francisco Estuary. Despite being protected for almost half a century and being included in a large number of recovery, restoration, and management plans, significant data gaps hinder conservation and management of the species, a...Smith, Katherine R.; Riley, Melissa K.; Barthman-Thompson, Laureen; Woo, Isa; Statham, Mark J.; Estrella, Sarah; Kelt, Douglas A.
Collision and displacement vulnerability to offshore wind energy infrastructure among marine birds of the Pacific Outer Continental Shelf
Marine birds are vulnerable to collision with and displacement by offshore wind energy infrastructure (OWEI). Here we present the first assessment of marine bird vulnerability to potential OWEI in the California Current System portion of the U.S. Pacific Outer Continental Shelf (POCS). Using population size, demography, life history,...Kelsey, Emily C.; Felis, Jonathan J.; Czapanskiy, Max; Peresksta, David M.; Adams, Josh
Prioritizing conserved areas threatened by wildfire and fragmentation for monitoring and management
In many parts of the world, the combined effects of habitat fragmentation and altered disturbance regimes pose a significant threat to biodiversity. This is particularly true in Mediterranean-type ecosystems (MTEs), which tend to be fire-prone, species rich, and heavily impacted by human land use. Given the spatial complexity of overlapping...Tracey, Jeff A.; Rochester, Carlton J.; Hathaway, Stacie A.; Preston, Kristine L.; Syphard, Alexandra D.; Vandergast, Amy G.; Diffendorfer, James E.; Franklin, Janet; MacKenzie, Jason B.; Oberbauer, Tomas A.; Tremor, Scott; Winchell, Clark S.; Fisher, Robert N.
Conservation genomics of the Mogollon Narrow-headed gartersnake (Thamnophis rufipunctatus) and Northern Mexican gartersnake (Thamnophis eques megalops)
The ability of populations to persist and adapt to abiotic and biotic changes is reliant on genetic diversity. When connectivity across a species landscape is disrupted, the levels and distribution of genetic diversity can rapidly deteriorate as a result of genetic drift, leading to increased inbreeding and reduced adaptive potential. Therefore,...Wood, Dustin A.; Emmons, Iain D.; Nowak, Erika M.; Christman, Bruce L.; Holycross, Andrew T.; Vandergast, Amy G.
A new approach to automated incubation recess detection using temperature loggers
Nest attendance during incubation is an important facet of avian nesting behavior, and understanding the number, timing, and duration of incubation recesses can improve our understanding of the factors determining avian reproductive success. Temperature loggers are a low-cost, noninvasive method for studying nest attendance, but processing and...Croston, Rebecca; Hartman, C. Alex; Herzog, Mark P.; Casazza, Michael L.; Ackerman, Joshua T.