Skip to main content

Hardin Waddle

thumbnail
Elucidating mechanisms underlying amphibian declines in North America using hierarchical spatial models
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...
thumbnail
All samples were collected within a 9km stretch of the Santa Fe River in northern Florida, USA. In 2019 and 2020 we sampled claw tissue from Macrochelys suwanniensis, Chelydra serpentina, and Trachemys scripta scripta, from three different sampling locations. We collected Vegetation and potential prey tissue samples within close proximity of turtle captures from two of the three capture locations. All tissues were used for stable carbon and nitrogen isotope analysis.
thumbnail
This dataset contains the results from 80 visual encounter surveys at two wetlands in Palmetto Island State Park, Vermillion Parish, Louisiana from August 2015 to April 2019. These surveys mainly targeted snakes but small turtles and anoles were also opportunistically captured. Captured animals were swabbed to determine the prevalence of Ophidiomyces ophiodiicola, the causative agent of Snake Fungal Disease. Physical measurements were taken on all captured individuals. This dataset also includes environmental data such as temperature, water level, and humidity at the study site.
thumbnail
This data release includes the data and computer code that we produced to fit two open-robust design removal models developed to simultaneously model population dynamics, temporary emigration, and imperfect detection: a random walk linear trend model (estimable without ancillary information), and a 2-age class integrated population model (IPM) that used prior information for age-structured vital rates and relative juvenile availability. To evaluate the effectiveness of management programs, we applied both models to a multi-year, removal trapping time-series data set of a large invasive lizard (Argentine black and white tegu, Salvator merianae) in three management areas of South Florida collected from 2016-1018....
thumbnail
Comma-separated values (.csv) file containing data related to amphibian sampling across the United States between 2016 and 2021. Data files contain mercury concentrations in amphibian and dragonfly tissues, mercury concentrations in sediment, as well as amphibian morphometrics, and habitat and climate characteristics where the samples were collected.
View more...
ScienceBase brings together the best information it can find about USGS researchers and offices to show connections to publications, projects, and data. We are still working to improve this process and information is by no means complete. If you don't see everything you know is associated with you, a colleague, or your office, please be patient while we work to connect the dots. Feel free to contact sciencebase@usgs.gov.