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Ophidiomycosis in snakes is caused by the fungus Ophidiomyces ophidiicola. Clinical signs associated with the disease range from minor skin lesions to severe swelling of the face. In some cases, the fungus invades the snake's underlying muscle and bone and internal organs; disease severity appears to peak during brumation. We quantified the prevalence of O. ophidiicola and ophidiomycosis in free-ranging snakes to explore seasonal variation in detection of the pathogen and disease. We collected skin swabs (n=464 samples) from seven species of free-ranging snakes (n=336) from Rondeau Provincial Park (Ontario, Canada) and tested the swabs for O. ophidiicola using quantitative PCR. We also assessed individuals for lesions consistent with ophidiomycosis and monitored changes in gross lesions over time in recaptured individuals. Eastern foxsnakes (Pantherophis vulpinus) had the highest prevalence of O. ophidiicola (24/84) and of lesions consistent with ophidiomycosis (34/84). On other species (Nerodia sipedon, Storeria dekayi, Thamnophis sirtalis, and Thamnophis sauritus), we detected the pathogen on only 4/229 snakes and observed gross lesions consistent with ophidiomycosis on 24/229 snakes. Body length of eastern foxsnakes was associated with detection of O. ophidiicola, suggesting that eastern foxsnakes' large size increases the risk of pathogen exposure relative to the other, smaller, species at our study site. Ophidiomyces ophidiicola and lesions consistent with ophidiomycosis were detected most frequently in eastern foxsnakes soon after emergence from brumation and less frequently later in the active season (O. ophidiicola: April=29.8%, October=3.9%; lesions: April=36.1%, October=5.5%). This decrease corresponded with resolution of lesions in 6/13 resampled eastern foxsnakes. Considering the seasonal cycle of O. ophidiicola and ophidiomycosis when planning disease surveillance research may improve detection probabilities for ophidiomycosis in Nearctic snakes.

Invasive species can significantly impact native wildlife by structurally altering habitats and access to resources. Understanding how native species respond to habitat modification by invasive species can inform effective habitat restoration, avoiding inadvertent harm to species at risk. The invasive graminoids Phragmites australis australis (hereafter Phragmites) and Typha × glauca are increasingly dominating Nearctic wetlands, often outcompeting native vegetation. Previous research suggests that turtles may avoid invasive Phragmites when moving through their home ranges, but the mechanisms driving avoidance are unclear. We tested two hypotheses that could explain avoidance of invaded habitat: (1) that stands of invasive macrophytes (Phragmites and Typha x glauca) impede movement, and (2) that they provide inadequate thermal conditions for turtles. We quantified active-season movements of E. blandingii (n = 14, 1328 relocations) and spotted turtles (Clemmys guttata; n = 12, 2295 relocations) in a coastal wetland in the Laurentian Great Lakes. Neither hypothesis was supported by the data. Phragmites and mixed-species Typha stands occurred within the home ranges of mature, active E. blandingii and C. guttata, and were used similarly to most other available habitats, regardless of macrophyte stem density. Turtles using stands of invasive macrophytes did not experience restricted movements or cooler shell temperatures compared to other wetland habitat types. Control of invasive macrophytes can restore habitat heterogeneity and benefit native wetland species. However, such restoration work should be informed by the presence of at-risk turtles, as heavy machinery used for control or removal may injure turtles that use these stands as habitat.

Habitat loss and road mortality pose severe threats to wildlife by reducing available resources, increasing mortality rates, and fragmenting remaining habitat into smaller patches. The combined threats of habitat loss and road mortality may amplify each other to increase extinction risks. Understanding how several threats can act alone or synergistically to affect species is key to implementing recovery actions. We tested how habitat loss and road density affect occupancy probability of reptiles, and how these factors interact, while accounting for the effects of climate on habitat suitability. We built occupancy models using observations of squamates (29,833 observations of 15 species) and turtles (39,925 observations of 7 species) from community science data in the Ontario Reptile and Amphibian Atlas. We predicted that habitat loss and road density would amplify each other and negatively affect occupancy probability. At the scale of our analyses (10 × 10 km squares used in this community science database), habitat loss negatively affected occupancy probability for 19 of 22 species, but the magnitude varied considerably between species. Surprisingly, road density did not affect occupancy of most species. Three species had synergistic effects of habitat loss and road density on occupancy, but the interaction terms had weak predictive power. Overall, habitat loss was a strong predictor of reptile occupancy, but there was not strong evidence that road density or the synergistic effects of habitat loss and road density negatively affected reptile occupancy in our study area. Future research should explore how the relative effects of habitat loss, road density and synergistic effects may differ at other spatial scales. Our results highlight the importance of conserving and restoring habitat to meet conservation goals for reptiles within our study area.

Roads are one of the most widespread human‐caused habitat modifications that can increase wildlife mortality rates and alter behavior. Roads can act as barriers with variable permeability to movement and can increase distances wildlife travel to access habitats. Movement is energetically costly, and avoidance of roads could therefore impact an animal's energy budget. We tested whether reptiles avoid roads or road crossings and explored whether the energetic consequences of road avoidance decreased individual fitness. Using telemetry data from Blanding's turtles (Emydoidea blandingii; 11,658 locations of 286 turtles from 15 sites) and eastern massasaugas (Sistrurus catenatus; 1,868 locations of 49 snakes from 3 sites), we compared frequency of observed road crossings and use of road‐adjacent habitat by reptiles to expected frequencies based on simulated correlated random walks. Turtles and snakes did not avoid habitats near roads, but both species avoided road crossings. Compared with simulations, turtles made fewer crossings of paved roads with low speed limits and more crossings of paved roads with high speed limits. Snakes made fewer crossings of all road types than expected based on simulated paths. Turtles traveled longer daily distances when their home range contained roads, but the predicted energetic cost was negligible: substantially less than the cost of producing one egg. Snakes with roads in their home range did not travel further per day than snakes without roads in their home range. We found that turtles and snakes avoided crossing roads, but road avoidance is unlikely to impact fitness through energetic expenditures. Therefore, mortality from vehicle strikes remains the most significant impact of roads on reptile populations.

Burton Richter had an enormous impact on the field of accelerator science and technology. This paper recounts some of that impact through seven short essays from people who viewed his contributions to aspects of the field with topics ranging from colliding beam rings, linear colliders to Free Electron Lasers.

Wildlife diversity and abundance are declining globally and population reinforcement with captive‐reared animals is a common intervention used to prevent extinctions. Released captive‐reared individuals may undergo an acclimation period before their behavior and success is comparable to wild‐reared individuals because they lack experience with predators, complex habitats and variable environmental conditions. Quantifying post‐release acclimation effects on fitness and behavior is important for maximizing the success of reintroduction programs and for predicting the number of captive‐reared animals required for release. Endangered Blanding's turtles Emydoidea blandingii exhibit low recruitment and may benefit from population reinforcement with captive‐reared, ‘headstarted’ individuals (headstarts). We used 6 years of data to compare survival, growth, habitat use and movement ecology between wild‐hatched juvenile turtles and headstarts reared from eggs rescued from injured females. We found strong evidence of an acclimation effect in headstarts, with lower movement, growth, and survival during the first one to two years post‐release. Following this acclimation period, headstarts had movement, growth and survival similar to wild‐hatched juveniles. Habitat use did not differ between headstarts and wild‐hatched juveniles. We hypothesize that the acclimation period occurred because headstarts were introduced directly into the wild (i.e. ‘hard release’) and that providing additional support before or after release may improve the success of headstarts. Headstarts had a monthly survival probability of 0.89 in the first year post‐release, and 0.98 after the first year post‐release. We estimated that headstarts at our sites have approximately three times higher probability of surviving to 10 years of age, compared to wild‐hatched individuals at other sites. Our results highlight that headstarts should be released into habitat individually rather than in clusters, and highlight the need to investigate whether post‐release mortality of captive‐reared animals could be mitigated by increased acclimation to wild conditions, for example through prerelease periods in outdoor pens.

Habitat selection models can explain spatial patterns in the relative abundance of animals in different habitats based on the assumption that fitness declines as density in a habitat increases. Ectotherms, such as lizards, may not follow predictions of density-dependent habitat selection models because temperature, which is unaffected by density, strongly influences their habitat selection. If competition for limited resources decreases fitness, then crowding should cause a decrease in body size and growth rates. We used skeletochronology and body size data from tree lizards (Urosaurus ornatus) at six sites that each spanned two habitats varying in quality to test the hypothesis that habitat selection is density dependent because growth is limited by competition for resources and by habitat quality. First, we tested that the maximum body size of lizards decreased with higher densities in a habitat by comparing growth between sites. Second, we tested whether body size and growth were higher in the habitat with more resources by controlling for density in a habitat and comparing growth between habitats in different sites. We found evidence of density-dependent growth in females, but not in males. Females in more crowded sites reached a smaller maximum size. Females in the higher quality habitat also grew larger than females in the lower quality habitat after controlling for differences in density between the habitats. Therefore, we found partial support for our hypothesis that competition for resources limits growth and causes density-dependent habitat selection.

Competition for resources is an important mechanism that shapes ecological communities. Interspecific competition can affect habitat selection, fitness, and abundance in animals. We used a removal experiment and mark–recapture to test the hypothesis that competition with the larger and more abundant Striped Plateau Lizard (Sceloporus virgatus H.M. Smith, 1938) limits habitat selection, fitness, and abundance in Ornate Tree Lizards (Urosaurus ornatus (Baird in Baird and Girard, 1852)). Ornate Tree Lizards in the plots where Striped Plateau Lizards were removed switched between habitat types more frequently and moved farther than Ornate Tree Lizards in control plots. However, there were no significant changes in the relative densities of Ornate Tree Lizards in each habitat type or in microhabitat use. We also found no changes in growth rates, survival, or abundance of Ornate Tree Lizards in response to the removal of Striped Plateau Lizards. Our results suggest that interspecific competition was not strong enough to limit habitat use or abundance of Ornate Tree Lizards. Perhaps interspecific competition is weak between coexisting species when resource levels are not severely depleted. Therefore, it is important to consider environmental conditions when assessing the importance of interspecific competition.

Density-dependent habitat selection has been used to predict and explain patterns of abundance of species between habitats. Thermal quality, a density-independent component of habitat suitability, is often the most important factor for habitat selection in ectotherms which comprise the vast majority of animal species. Ectotherms may reach high densities such that individual fitness is reduced in a habitat due to increased competition for finite resources. Therefore, density and thermal quality may present conflicting information about which habitat will provide the highest fitness reward and ectotherm habitat selection may be density-independent. Using ornate tree lizards Urosaurus ornatus at 10 sites each straddling two adjacent habitats (wash and upland), we tested the hypothesis that habitat selection is density-dependent even when thermal quality differs between habitats. We first tested that fitness proxies decline with density in each habitat, indicating density-dependent effects on habitat suitability. We also confirmed that the two habitats vary in suitability (quantified by food abundance and thermal quality). Next, we tested the predictions that habitat selection depends on density with isodar analyses and that fitness proxies are equal in the two habitats within a site. We found that monthly survival rates decreased with density, and that the wash habitat had more prey and higher thermal quality than the upland habitat. Lizards preferred the habitat with more food and higher thermal quality, lizard densities in the two habitats were positively correlated, and fitness proxies of lizards did not differ between habitats. These patterns are consistent with density-dependent habitat selection, despite differences in thermal quality between habitats. We expect that density-dependent habitat selection is widespread in terrestrial ectotherms when densities are high and temperatures are close to their optimal performance range. In areas where thermal quality is low, however, we expect that depletable resources, such as food, become less limiting because assimilating resources is more difficult. This article is protected by copyright. All rights reserved.

Wildlife rehabilitation is the treatment and subsequent release of injured wildlife. Wildlife rehabilitation benefits individual animals receiving care, but also supports Conservation Medicine approaches by providing opportunities to monitor wildlife health, contaminant loads, and disease prevalence. However, it is typically considered to have negligible effects on population growth, and has not traditionally been acknowledged as an effective tool for wildlife conservation. To explore whether rehabilitation and release could directly support population recovery in some cases (i.e., increase population growth rates), we considered five case study species along a spectrum of life-history strategies (Raccoon, Painted Turtle, Blanding’s Turtle, Snapping Turtle, and Little Brown Bat). We simulated populations over 200 years, while varying two parameters: 1) the rate of severe injury (0, 1, 2, or 5 % of the population); and 2) how many of these injured animals are successfully rehabilitated (0, 10, 25, or 50 %). The effect of the rehabilitation scenarios was largest when additive severe injury rates were highest (5 %). Species that were most sensitive to increased adult injury rates (turtles and bats) also exhibited the greatest population-level responses to rehabilitation and release interventions. We conclude that wildlife rehabilitation can support in situ recovery and help stabilize declining populations when 1) injury is an ongoing source of high additive mortality, 2) the target population is small, 3) the species exhibits a K-selected life-history strategy, 4) rehabilitation can be combined with other interventions, including in situ threat mitigations, and 5) rehabilitation efforts do not jeopardize or limit in situ conservation interventions.

Almost all turtle species nest in terrestrial environments and maternal site selection represents a critical component of nest success. Females use cues in the current environment to predict the future conditions for embryo development. However, in disturbed landscapes, current and future conditions may not be correlated. We compared selection of nest sites by Blanding’s Turtles (Emydoidea blandingii (Holbrook, 1838)) in a (relatively undisturbed) park and a (heavily disturbed) agricultural landscape in Ontario, Canada, using field measurements and satellite imagery. Environmental variables were compared using logistic regression and Akaike’s information criterion (AIC) based on data measured at nest (presence) and random (pseudoabsence) locations. Specific environmental variables associated with site selection differed between study areas. Most notably, NDVI (normalized difference vegetation index, a proxy for vegetation cover) increased significantly during the year at the agricultural locale, corresponding with the growth of planted fields. No parallel change was observed at the park locale where canopy cover remained more consistent. An increase in vegetation cover may alter nest temperatures and soil moisture. Combined with the unpredictability in timing of crop sowing and harvesting, findings suggest that nests in agricultural fields may act as ecological sinks and that other species nesting in similarly altered habitats may be subjected to the same threats.

Biological invasions are a prominent factor contributing to global biodiversity loss. As a result, managing invasive species is a priority for many conservation scientists and natural resource managers. Invasive species management requires a multidisciplinary approach and there is increasing recognition that physiology can be used to inform conservation efforts because physiological processes underlie an individual’s response to its environment. For example, physiological concepts and tools can be used to assess the impacts of invasive animals on their new ecosystems, to predict which animal species are likely to become invasive, to prevent the introduction of non-native animals, and to control incipient or established invasions. To evaluate whether physiology is integrated within invasion science, the journal Biological Invasions was surveyed for a quantitative literature review. To determine how physiology is used to inform invasion science and which subdisciplines of physiology are particularly relevant to invasive animal management, the broader invasion literature was also reviewed to identify examples where physiology has contributed to studying and managing invasive animals. Only 6 % of articles published in Biological Invasions incorporated physiological knowledge or tools, mostly for the purposes of identifying traits associated with species invasiveness (i.e. prediction). However, the broader literature indicated that successful invasive species research and management can be supported by fundamental and applied physiological research for assessing, predicting, preventing, and controlling invasive animals. Development of new techniques and increased availability of equipment for remote or rapid monitoring of physiology in the field will increase opportunities for integrating physiology within invasion science.

Iteroparous species invest little energy into annual reproduction and tend to experience low and variable survivorship in young life stages. However, juveniles with traits that increase survival will have a fitness advantage over conspecifics, and usually bigger is better for juvenile vertebrates. Understanding behavioural and morphological characteristics that increase fitness is important for our understanding of the evolution of life-history strategies. We outfitted naturally emerging hatchlings of two species of turtles (Blanding's turtles Emydoidea blandingii and wood turtles Glyptemys insculpta) with radio transmitters to test five hypotheses related to survival from nests to overwintering sites using logistic regression models. In contrast to the widely supported hypothesis that bigger is better for survival of juveniles, we found that smaller hatchlings of both species were more likely to survive from emergence to overwintering. In E. blandingii, hatchlings that emerged later in the year, which reduced exposure time to predators and environmental risks, and spent less time in upland open habitat, were also more likely to survive. Our results demonstrate that bigger is not always better in juvenile ectotherms. Assuming bigger is better without observations of survival can lead to erroneous conclusions related to fitness proxies and the ontogeny of body size in populations. The observed relationship between habitat selection and survival in E. blandingii indicates a direct link between behaviour (habitat selection) and fitness through mortality caused by predators and environmental stressors.

Fitness proxies such as performance measures are used to quantify relative fitness in systems where direct measurements are unobtainable. To provide meaningful results at the individual level, fitness proxies must demonstrate not only repeatability, as measured by high intraclass correlation coefficients, but also rank repeatability. Here we illustrate the importance of rank repeatability in fitness proxies using a commonly employed example: righting time in hatchling turtles. Our results show that individual righting time varies strongly among trials and is not replicable enough to provide repeatable rankings of individuals or clutches. To illustrate the potential implications of this finding, we use our data to test the predication that larger turtles have faster righting times, using three consecutive trials of righting time. The resulting conclusions vary substantially among trials. Thus, we conclude that righting time does not meet the criterion of rank repeatability required for estimates of relative individual fitness, performance or phenotypic quality. Researchers employing similar proxies should assess the rank repeatability of a proxy before applying it to questions of relative individual fitness. If a measure shows satisfactory repeatability, the final test for a fitness proxy is to demonstrate a correlation with actual fitness, ideally in the organism's natural habitat.

The viability of freshwater turtle populations is largely dependent on the survivorship of reproducing females but females are frequently killed on roads as they move to nesting sites. Installing artificial nesting mounds may increase recruitment and decrease the risk of mortality for gravid females by enticing them to nest closer to aquatic habitats. We evaluated the effectiveness of artificial nesting mounds installed in Algonquin Park, Canada. Artificial mounds were monitored for 2 years to determine if turtles would select them for nest sites. We also simulated turtle paths from wetlands to nests to determine the probability that females would encounter the new habitat. A transplant experiment with clutches ofChrysemys pictaandChelydra serpentinaeggs compared nest success and incubation conditions in the absence of predation between artificial mounds and natural sites. More turtles than expected used the artificial mounds, although mounds comprised a small proportion of the available nesting habitat and the simulations predicted that the probability of females encountering mounds was low. Hatching success was higher in nests transplanted to artificial mounds (93%) than in natural nests (56%), despite no differences in heat units. Greater use than expected, high hatching success, and healthy hatchlings emerging from nests in artificial mounds suggest promise for their use as conservation tools.

Partitioning of the niche space is a mechanism used to explain the coexistence of similar species. Ectotherms have variable body temperatures and their body temperatures influence performance and, ultimately, fitness. Therefore, many ectotherms use behavioral thermoregulation to avoid reduced capacities associated with body temperatures far from the optimal temperature for performance. Several authors have proposed that thermal niche partitioning in response to interspecific competition is a mechanism that allows the coexistence of similar species of ectotherms. We reviewed studies on thermal resource partitioning to evaluate the evidence for this hypothesis. In almost all studies, there was insufficient evidence to conclude unequivocally that thermal resource partitioning allowed species coexistence. Future studies should include sites where species are sympatric and sites where they are allopatric to rule out alternative mechanisms that cause differences in thermal traits between coexisting species. There is evidence of conservatism in the evolution of most thermal traits across a wide range of taxa, but thermal performance curves and preferred temperatures do respond to strong selection under laboratory conditions. Thus, there is potential for selection to act on thermal traits in response to interspecific competition. Nevertheless, more stringent tests of the thermal resource partitioning hypothesis are required before we can assess whether it is widespread in communities of ectotherms in nature.

Corrigendum Corrigendum to “When righting is wrong: performance measures require rank repeatability for estimates of individual fitness” [Animal Behaviour 93 (2014) 15e23] C. M. Davy a, b, , J. E. Paterson c, , A. E. Leifso a, 2 a Wildlife Preservation Canada, Guelph, ON, Canada b Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada c Department of Biology, University of Ottawa, Ottawa, ON, Canada

Context Turtles are one of the most imperilled taxonomic groups worldwide and information about population ecology is essential to species recovery. Although the spatial ecology and demography of adults of several turtle species have been well studied, little is known about early life stages. The small size, soft shell, and limited mobility of hatchling turtles may cause differences in survivorship and habitat selection compared with adults. Aims We tested the hypothesis that hatchling turtles select habitat as they move away from nests, so as to reduce the risk of predation and desiccation. Methods We examined survivorship, behaviour and habitat selection at two spatial scales in hatchling Blanding’s turtles (Emydoidea blandingii) and wood turtles (Glyptemys insculpta) in 2009 and 2010, using radio-telemetry in Algonquin Provincial Park, Ontario, Canada. In addition, temperatures of sites used by hatchlings during winter were compared with those at haphazard stations in various habitats. Key results The mortality rate was high, with 42% of E. blandingii and 11% of G. insculpta hatchlings surviving to winter; most mortality was caused by predation. Most behavioural observations for both species were of individuals hiding under cover. Both species showed evidence of macrohabitat and microhabitat selection as they dispersed from nests towards overwintering sites, and important variables in the models differed between species. Likewise, the adult stages of these two species differ in their macrohabitat specialisation. There was also evidence that hatchlings chose overwintering sites on the basis of temperature. Conclusions Despite significant differences in survivorship between hatchlings and adults, resource selection was similar between these two demographic stages, and conservation plans based on adult habitat use should simultaneously protect hatchlings. Implications Understanding habitat selection by juveniles is important for testing hypotheses about ontogenetic shifts in resource selection and for protecting habitat for species at risk.