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Translocation is increasingly used to move animals of conservation concern away from sites where habitat will be destroyed (mitigation translocation), but outcomes have rarely been adequately monitored, particularly for amphibians. We used radiotelemetry monitoring to assess survival and movement of 23 experimentally translocated, adult Gopher Frogs (Lithobates capito) at a recipient site in north-central Florida, USA. Although posttranslocation monitoring was our primary goal, we also compared our results with those of 24 nontranslocated frogs that were monitored in three previous efforts, conducted at different locations and times. For both translocated and nontranslocated frogs, movement was the most important predictor of mortality, with translocated frogs having a significantly higher probability of movement and higher mortality during the first month following release. However, there was no effect of translocation on survival after controlling for probability of movement because movement was dangerous for both translocated and nontranslocated frogs. Movement by translocated frogs was likely a behavioral response to the translocation experience, whereas movement by nontranslocated frogs was associated with breeding pond visitation, which was not observed within the translocated group. Survival was high for both groups once they settled into underground refugia and movement declined. Despite the comparatively high mortality of translocated frogs immediately following release, more than half survived to the end of monitoring and remained in the vicinity of the release site, meeting an early benchmark of translocation success. [ABSTRACT FROM AUTHOR]

Range‐wide species conservation efforts are facilitated by spatially explicit estimates of habitat suitability. However, species‐environment relationships often vary geographically and models assuming geographically constant relationships may result in misleading inferences. We present the first range‐wide habitat suitability model (HSM) for the federally threatened eastern indigo snake (Drymarchon couperi) as a case study illustrating an approach to account for known latitudinal variation in habitat associations. Specifically, we modeled habitat suitability using interactive relationships between minimum winter temperature and several a priori environmental covariates and compared our results to those from models assuming geographically constant relationships. We found that multi‐scale models including interactive effects with winter temperature outperformed single‐scale models and models not including interactive effects with winter temperature. Our top‐ranked model had suitable range‐wide predictive performance and identified numerous large (i.e., ≥1000 ha) potential habitat patches throughout the indigo snake range. Predictive performance was greatest in southern Georgia and northern Florida likely reflecting more restrictive indigo snake habitat associations in these regions. This study illustrates how modeling interactive effects between temperature and environmental covariates can improve the performance of HSMs across geographically varying environmental gradients. [ABSTRACT FROM AUTHOR]

Landscape features can strongly influence gene flow and the strength and direction of these effects may vary across spatial scales. However, few studies have evaluated methodological approaches for selecting spatial scales in landscape genetics analyses, in part because of computational challenges associated with optimizing landscape resistance surfaces (LRS). We used the federally threatened eastern indigo snake (Drymarchon couperi) in central Florida as a case study with which to compare the importance of landscape features and their scales of effect in influencing gene flow. We used genetic algorithms (ResistanceGA) to empirically optimize LRS using categorical land cover surfaces, multiscale resource selection surfaces (RSS), and four combinations of landscape covariates measured at multiple spatial scales (multisurface multiscale LRS). We compared LRS where scale was selected using pseudo‐ and full optimization. Multisurface multiscale LRS received more empirical support than LRS optimized from categorical land cover surfaces or RSS. Multiscale LRS with scale selected using full optimization generally outperformed those with scale selected using pseudo‐optimization. Multiscale LRS with large spatial scales (1200–1800 m) received the most empirical support. Our results highlight the importance of considering landscape features across multiple spatial scales in landscape genetic analyses, particularly broad scales relative to species movement potential. Different effects of scale on home range‐level movements and dispersal could explain weak associations between habitat suitability and gene flow in other studies. Our results also demonstrate the importance of large tracts of undeveloped upland habitat with heterogenous vegetation communities and low urbanization for promoting indigo snake connectivity. [ABSTRACT FROM AUTHOR]

Many snake populations display seasonal variation in movement patterns in response to spatiotemporal variation in prey, mates, and other resources. Eastern Indigo Snakes (Drymarchon couperi) are federally threatened and endemic to the southeastern coastal plain of the United States. Although previous studies have described seasonal variation in D. couperi movement patterns at the northern limit of their range (southern Georgia), such information is currently lacking from peninsular Florida. We describe sex-specific seasonal variation in D. couperi movement patterns and space use in peninsular Florida across multiple temporal scales. We found that males made longer, more frequent movements, and had larger home ranges than females during the winter breeding season. Although movement frequency and distance were similar between sexes during the nonbreeding season, males still had larger home ranges. The degree of within-individual home-range overlap was consistent over time and not indicative of seasonal migrations between winter and summer habitats. Our observations of increased male movements during the winter are consistent with observations of breeding activity by snakes at our study sites, and across the species' range. The levels of winter activity that we observed for D. couperi contrast with the spring/autumn breeding seasons and low winter activity reported for other North American snake species. In contrast to our results, previous studies of D. couperi in southern Georgia found that both sexes exhibited the lowest rates of movement and smallest home-range sizes during winter, despite the occurrence of breeding activity. We hypothesize that differences in winter climate between these two areas allow for greater surface activity among snakes in peninsular Florida. [ABSTRACT FROM AUTHOR]