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Most translocation efforts are unsuccessful, often for unknown reasons. We assessed factors linked with population persistence for 25 years of translocations of the federally threatened Chiricahua Leopard Frog. Local features were paramount, including habitat, predators, and restoration history. Timing and life stages stocked affected persistence, but rearing environment did not. Two or more translocations produced an approximate 4-yr increase in predicted population persistence.

To inform responsible energy development, it is important to understand the ecological effects of contamination events. Wastewaters from oil and gas extraction often contain high concentrations of sodium chloride (NaCl) and heavy metals (e.g., strontium and vanadium), but studies of their influence on microbial communities are limited. We sampled water, sediment, and larval amphibian skin (four species) across a gradient of contamination (0.04–17500 mg/L Cl) in a large energy production area of North America. NaCl concentrations affected the similarity among microbiomes of water, sediment, and amphibian skin, but not the diversity or richness of water and skin microbiomes. Strontium concentrations were associated with lower diversity and richness of sediment microbial communities. Amphibian microbiomes were similar to those of water, but not sediment, and sediment microbiomes were similar to those of water. Species identity was the strongest predictor of amphibian microbiomes; frog microbiomes were similar but differed from that of the salamander, whose microbiome had the lowest richness and diversity. Understanding whether effects of wastewaters on microbial communities also influences their ecosystem function will be an important next step. Our study provides novel insight into associations among different wetland microbial communities and effects of wastewaters from energy production.

Dedicated long-term monitoring at appropriate spatial and temporal scales is necessary to develop effective conservation plans. Using an amphibian monitoring program for a network of U.S. National Parks, we compare monitoring program designs. Designs that reduce biases in parameter estimates are needed to guide conservation policy and management decisions in the face of broad scaled environmental challenges; the optimal design is sensitive to the specific objectives of a monitoring program.

This website provides an application for exploring modeling results from a U.S. Geological Survey (USGS) project titled Mapping Climate Change Resistant Vernal Pools in the Northeastern U.S. The purpose of this project was to improve understanding of the factors that control inundation patterns in vernal pools of the northeastern United States, so as to identify pools that might function as hydrologic refugia under climate change.

Altered flow regimes can contribute to dissociation between life history strategies and environmental conditions, leading to reduced persistence reported for many wildlife populations inhabiting regulated rivers. The Oregon spotted frog Rana pretiosa is a threatened species occurring in floodplains, ponds, and wetlands in the Pacific Northwest with a core range in Oregon, USA. All life stages of R. pretiosa are reliant on aquatic habitats, and inundation patterns across the phenological timeline can have implications for population success. We conducted capture–mark–recapture (CMR) sampling of adult and subadult R. pretiosa at three sites along the Deschutes River downstream from two dams that regulate flows. We related the seasonal extent of inundated habitat at each site to monthly survival probabilities using a robust design CMR model. We also developed matrix projection models to simulate population dynamics into the future under current river flows. Monthly survival was strongly associated with the extent and variability of inundated habitat, suggesting some within-season fluctuations at higher water levels could be beneficial. Seasonal survival was lowest in the winter for all three sites, owing to limited water availability and the greater number of months within this season relative to other seasons. Population growth for the two river-connected sites was most strongly linked to adult survival, whereas population growth at the river-disconnected site was most strongly tied to survival in juvenile stages. This research identifies population effects of seasonally limited water and highlights conservation potential of enhancing survival of particularly influential life stages.

We observed multiple toads in amplexus and depositing egg strings among the vegetation. The following night (2230 h on 28 May 2021) a convergence of over a dozen Western Tiger Salamander (Ambystoma mavortium) individuals was observed consuming A. boreas eggs that had been deposited 24-48 hours earlier

Northern Red-Bellied Cooters (Pseudemys rubriventris) have a disjunct distribution with a relictual population in southeastern Massachusetts and a larger range across the mid-Atlantic United States. The relictual population is currently listed with protections under the U.S. Endangered Species Act but the status of the population in the remainder of the species' range has not been assessed, and there is concern that it may be at risk of extinction without protection. The U.S. Fish and Wildlife Service requires scientific information of the species' status to inform conservation decisions. There is little empirical information available from P. rubriventris[I/] populations and, furthermore, the majority of what exists comes from the disjunct northern subpopulation. To fill data gaps in the species' life history and reduce geographic bias, we supplement available data from P. rubriventris[I/] with demographic rate estimates from other Pseudemys species to parameterize an age-structured population projection model. Our estimate of mean population growth rate was https://0.987 (0.92–1.04), indicating that P. rubriventris[I/] populations may be in decline. However, there was considerable uncertainty in our results, with 35% of projections resulting in stable or increasing populations. Additional uncertainty about parameter values, geographic variation, and current threats limit the assessment. We discuss the merits and limitations of our population projection modeling (PPM) approach where other analytical methods are precluded by lack of available data.