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Robert N Fisher

Supervisory Research Biologist

Western Ecological Research Center

Office Phone: 619-225-6422
Fax: 619-225-6436
ORCID: 0000-0002-2956-3240

Supervisor: Diane R Elam
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.
Amphibian populations are declining globally at unprecedented rates but statistically rigorous identification of mechanisms is lacking. Identification of reasons underlying large-scale declines is imperative to plan and implement effective conservation efforts. Most research on amphibian population decline has focused on local populations and local factors. However, the ubiquity of declines across species and landscapes suggests that causal factors at a broader scale are also important. Elucidation of the mechanisms driving population change has lagged, mainly because data have been unavailable at continental scales. We propose to address this need by assembling data to answer questions about broad-scale drivers...
Observations (reduced to detected/not detected) of 45 vertebrate species (seven mammals, seven amphibians, and 31 reptiles) across Southern California pitfall sampling projects conducted between 1995 through 2015. Habitat patch locations of every pitfall sampling project presented in a shapefile. Habitat patches were measured based on the size when pitfall sampling began within each. Sampling projects within the same geographic area may have different sized patches based on date of project sampling and if patch erosion occurred. A matrix of whether each species was expected within each habitat patch's species pool based on range maps and published records is also included. These data support the following publication:...
These data consist of microsatellite genotype scores for all samples of Santa Ana sucker (Catostomus santaanae) used in the study. Scores represent the allele calls for each microsatellite locus (i.e. DNA fragment length containing the microsatellite repeats), with each locus containing two scores representing the two allele copies detected. Included are five tables: Full dataset (includes genotypes from all samples), Santa Clara River samples only (includes genotypes only from samples collected in the Santa Clara River), Convert File format key (explains the data file format), Population identifiers (translates the numerical population identifiers to actual collecting sites), CASA sampling points (one coordinate...
The data set consists of 12 input data rasters that cover San Diego County, California. These input rasters represent criteria used in a Pareto ranking algorithm in the manuscript. These include three rasters related to fire threats, three rasters related to habitat fragmentation threats, four rasters related to species biodiversity, and two rasters related to genetic biodiversity. (see the PLOS ONE paper for details). These data support the following publication: Tracey JA, Rochester CJ, Hathaway SA, Preston KL, Syphard AD, Vandergast AG, et al. (2018) Prioritizing conserved areas threatened by wildfire and fragmentation for monitoring and management. PLoS ONE 13(9): e0200203.
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