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This dataset includes data on the growth, fecundity, and survival of Giant Gartersnakes (Thamnophis gigas) in the Sacramento Valley of California from 1995-2017. These data support the following publication: Rose, J.P., Ersan, J.S., Wylie, G.D., Casazza, M.L. and Halstead, B.J., 2019. Demographic factors affecting population growth in giant gartersnakes. The Journal of Wildlife Management, 83(7), pp.1540-1551.
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The dataset consists of two csv files one for home range and net displacement analysis for adult snakes with at least 20 locations collected during the study period and one for the analysis of movement metrics for all adult snakes in the study. The home range data contains the calculated 100 percent and 95 percent minimum convex polygons (MCP) and 95 percent adaptive local convex hull (a-LoCoH) home range estimates, 3 measures of net displacement from the release location of the snake as well as other pertinent information about individual snakes (year included in study, id, treatment group, site, snout to vent length (SVL)). The movement data contains calculations of the following movement metrics: sinuosity, start-to-end...
Many coastal dune ecosystems have been degraded by non-native dune vegetation, but these systems might still provide valuable habitat for some taxa, including amphibians. Because restoration of degraded dune systems is occurring and likely to continue, we examined the occurrence of amphibians in drainages associated with a coastal dune ecosystem degraded by invasive plants (European Beachgrass, Ammophila arenaria, and Iceplant, Carpobrotus edulis). We found that occupancy of three amphibian species (California Red-legged Frog, Rana draytonii; sierran treefrog, Pseudacris sierra; and Rough-skinned Newt, Taricha granulosa) among 21 coastal dune drainages was high, with most coastal dune drainages occupied by all three...
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These data provide information on the survival of California red-legged frogs in a unique ecosystem to better conserve this threatened species while restoring habitat for rare dune plants and animals.
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This dataset includes data on the growth, fecundity, and survival of Giant Gartersnakes (Thamnophis gigas) in the Sacramento Valley of California from 1995-2017. In addition, the dataset includes R code to replicate the Integral Projection Model construction and analysis presented in the paper "Demographic drivers of population growth in a threatened snake" by Rose et al. published in Journal of Wildlife Management in 2019. These data support the following publication: Rose, J.P., Ersan, J.S., Wylie, G.D., Casazza, M.L. and Halstead, B.J., 2019. Demographic factors affecting population growth in giant gartersnakes. The Journal of Wildlife Management, 83(7), pp.1540-1551.
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These data are from joint visual encounter and environmental DNA (eDNA) surveys conducted for northwestern pond turtles (Actinemys marmorata) in streams on privately-owned timberlands in northern California.
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This is an examination of the diet of a threatened snake, giant gartersnake (Thamnophis gigas). Prey preference, prey selection and prey availability (in the laboratory and the field) were measured to understand prey dynamics for better conservation of this snake. In the laboratory, olfactory trials were performed on neonate snakes and tongue-flicks, lounges and attacks were counted and calculated into 'tongue-flick attack scores', a measure of prey preference. Prey-choice trials were used to measure prey selection in the laboratory. In the field, we measured prey choice and prey availability to gain an understanding of prey choice in nature. These data support the following publication: Ersan, J.S., Halstead,...
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Stream-obligate amphibians are important indicators of ecosystem health in the Pacific Northwest, but distributional information to improve forest management is lacking in many regions. We analyzed archived DNA extracted from water samples in 60 pools within streams in private timberlands in Mendocino County, California, for 3 California Species of Special Concern - Coastal Tailed Frogs (Ascaphus truei), Foothill Yellow-legged Frogs (Rana boylii), and Southern Torrent Salamanders (Rhyacotriton variegatus) - to better understand their distributions in the region. These data support the following publication: Brian J Halstead, Caren S Goldberg, Robert B Douglas, Patrick M Kleeman, and David W Ulrich "OCCURRENCE OF...
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We used genome-wide single nucleotide polymorphism (SNP) data and capture-mark-recapture methods to evaluate the genetic diversity and demography within seven focal sites of the endangered San Francisco gartersnake (Thamnophis sirtalis tetrataenia). As Thamnophis sirtalis tetrataenia is listed as endangered by the U.S. Fish and Wildlife Service (USFWS), sensitive location information can be made available upon request by contacting Brian J. Halstead and/or Amy G. Vandergast.
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Locations of sites at which U.S. Geological Survey (USGS) biologists surveyed for Temblor legless lizards (Anniella alexanderae) in 2022 and 2023 and the results of those surveys. At the time of the species description, little was known about the distribution of the Temblor legless lizard beyond a few localities. Surveys were designed to gather information on the distribution of Temblor legless lizards to help inform a Species Status Assessment by the U.S. Fish and Wildlife Service. Binary values for each year indicate whether Temblor legless lizards were detected under cover boards at a site in that year (1) or were not detected at that site in that year (0). Non-detection of Temblor legless lizards at a site does...
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These data provide information on the relationship between California red-legged frogs and their habitat in a unique ecosystem to better conserve this threatened species while restoring habitat for rare dune plants and animals.
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We compiled time series of egg mass counts (an index of adult female abundance) from Rana boylii populations in 36 focal streams and fit a Multiple Population Viability Analysis (MPVA) model to quantify how streamflow metrics, stream temperature, and surrounding land cover affect population growth. In addition, data on streamflow, stream temperature, and surrounding land cover for each stream were compiled from existing sources. These data support the following publication: Rose, J.P., Kupferberg, S.J., Peek, R.A., Ashton, D., Bettaso, J.B., Bobzien, S., Bourque, R.M., Breedveld, K.G., Catenazzi, A., Drennan, J.E., Gonsolin, E., Grefsrud, M., Herman, A.E., House, M.R., Kluber, M.R., Lind, A.J., Marlow, K.R., Striegle,...


map background search result map search result map Habitat Selection of California Red-Legged Frogs in Point Reyes Coastal Dune Drainages (2015) Survival of California Red-Legged Frogs in Point Reyes Coastal Dune Drainages (2015) Hydrological measurements of 300 US temporary wetlands from 2004-2014 Code and Data Files to Construct an Integral Projection Model for Giant Gartersnakes (Thamnophis gigas) in the Sacramento Valley, California, 1995-2017 Data files Characteristics of Sites Sampled for eDNA of Amphibians in Mendocino County, California, 2016 Genomic and Demographic Data from the San Francisco Gartersnake Giant Gartersnake (Thamnophis gigas) Prey Preference (2014) Survey Results for Temblor Legless Lizards (Anniella alexanderae) in the San Joaquin Valley of California, 2022 and 2023 Egg Mass Counts from Foothill Yellow-Legged Frogs (Rana boylii) in California from 1992-2021 Northwestern Pond Turtle Survey Data in Northern California Forest Streams, 2021-2022 Home Range and Movement Metric Data of Resident and Translocated Giant Gartersnakes (Thamnophis gigas) in Sacramento, CA, USA, in 2018 to 2021 Habitat Selection of California Red-Legged Frogs in Point Reyes Coastal Dune Drainages (2015) Survival of California Red-Legged Frogs in Point Reyes Coastal Dune Drainages (2015) Characteristics of Sites Sampled for eDNA of Amphibians in Mendocino County, California, 2016 Giant Gartersnake (Thamnophis gigas) Prey Preference (2014) Code and Data Files to Construct an Integral Projection Model for Giant Gartersnakes (Thamnophis gigas) in the Sacramento Valley, California, 1995-2017 Data files Survey Results for Temblor Legless Lizards (Anniella alexanderae) in the San Joaquin Valley of California, 2022 and 2023 Northwestern Pond Turtle Survey Data in Northern California Forest Streams, 2021-2022 Genomic and Demographic Data from the San Francisco Gartersnake Egg Mass Counts from Foothill Yellow-Legged Frogs (Rana boylii) in California from 1992-2021 Hydrological measurements of 300 US temporary wetlands from 2004-2014