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Stephanie Galvan

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Batrachochytrium dendrobatidis is a fungal pathogen that is receiving attention around the world for its role in amphibian declines. Study of its occurrence patterns is hampered by false negatives: the failure to detect the pathogen when it is present. Occupancy models are a useful but currently underutilized tool for analyzing detection data when the probability of detecting a species is <1. We use occupancy models to evaluate hypotheses concerning the occurrence and prevalence of B. dendrobatidis and discuss how this application differs from a conventional occupancy approach. We found that the probability of detecting the pathogen, conditional on presence of the pathogen in the anuran population, was related to...
Categories: Publication; Types: Citation; Tags: Ecological Applications
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***This dataset is superseded by Adams, M.J., Pearl, C.A., McCreary, B., Galvan, S.K., and Rowe, J.C., 2019, Oregon Spotted Frog (Rana pretiosa) Monitoring at Jack Creek 2015-2018 (final): U.S. Geological Survey data release, https://doi.org/10.5066/P9L2XC5B.*** This dataset contains information from mark-recapture surveys conducted in 2015 by USGS as part of an ongoing Oregon spotted frog (Rana pretiosa) monitoring effort at Jack Creek, Klamath County, Oregon. Data consist of spotted frog counts aggregated by date, location, life stage, and sex, as well data on environmental conditions at the time of each survey.
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This dataset contains information from visual encounter surveys conducted between 2012 and 2016 by USGS as part of an ongoing Oregon spotted frog (Rana pretiosa) monitoring effort in the Oregon Cascade Mountain Range. We surveyed 91 sites using a rotating frame design in the Klamath and Deschutes Basins, Oregon, which encompass most of the species' core extant range. Data consist of spotted frog counts aggregated by date, location, and life stage, as well as data on environmental conditions at the time of each survey.
Categories: Publication; Types: Citation
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This dataset contains information from surveys conducted 2010-2018 by USGS as part of a long-term Oregon spotted frog monitoring effort in the central Oregon range. Data consist of site, survey, habitat, and species detection covariates, as well as inter-site distance measurements.
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Non-native fish and bullfrogs (Lithobates catesbeianus; Rana catesbeiana) are frequently cited as factors contributing to the decline of ranid frogs in the western United States (Bradford 2005). This hypothesis is supported by studies showing competition with or predation by these introduced species (Kupferberg 1997, Kiesecker and Blaustein 1998, Lawler et al. 1999, Knapp et al. 2001) and studies suggesting a deficit of native frogs at sites occupied by bullfrogs or game fish (Hammerson 1982, Schwalbe and Rosen 1988, Fisher and Shaffer 1996, Adams 1999). Conversely, other studies failed to find a negative association between native ranids and bullfrogs and point out that presence of non-native species correlates...
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