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Brian J Halstead

Supv. Research Wildlife Biologist

Western Ecological Research Center

Office Phone: 530-669-5076
Fax: 707-678-5039
ORCID: 0000-0002-5535-6528

800 Business Park Drive
Dixon , CA 95620

Supervisor: Tom S Kimball
We conducted a radio telemetry study of adult western spadefoots (Spea hammondii) at 2 sites in southern California to characterize their survival, behavior, and movements from breeding through aestivation to inform conservation and management for the species. These data support the following publication: Halstead, B.J., Baumberger, K.L., Backlin, A.R., Kleeman, P.M., Wong, M.N., Gallegos, E.A., Rose, J.P., and Fisher, R.N., 2021. Conservation implications of spatiotemporal variation in the terrestrial ecology of an ephemeral pool-breeding amphibian. The Journal of Wildlife Management.
These data include egg mass counts and adult capture-mark-recapture histories for Foothill Yellow-legged frogs (Rana boylii) at two streams in northern California. Data were collected from the South Fork Eel River and its tributary, Fox Creek, from 1993-2019. Data from Hurdygurdy Creek were collected from 2002-2008.
This U.S. Geological Survey data release includes tabular data collected to characterize the habitat and movement of Dixie Valley toads. Data were collected in Dixie Valley, Nevada, in autumn 2018 and spring 2019. These data support the following publication: Halstead, B.J., Kleeman, P.M., Rose, J.P. and Fouts, K.J., 2021. Water Temperature and Availability Shape the Spatial Ecology of a Hot Springs Endemic Toad (Anaxyrus williamsi). Herpetologica, 77(1), pp.24-36.
Conversion and fragmentation of wildlife habitat often leads to smaller and isolated populations and can reduce a species’ ability to disperse across the landscape. As a consequence, genetic drift can quickly lower genetic variation and increase vulnerability to extirpation. For species of conservation concern, quantification of population size and connectivity can clarify the influence of genetic drift in local populations and provides important information for conservation management and recovery strategies. Here, we used genome-wide single nucleotide polymorphism (SNP) data and capture-mark-recapture methods to evaluate the population structure, genetic diversity and abundance of seven focal sites of the endangered...
These data describe the location (terrestrial or aquatic) and activity status (active or inactive) of giant gartersnakes (Thamnophis gigas) by individual and location.
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