Aim: Predicting environmentally suitable areas for non-native species is an important step in managing biotic invasions, and ecological niche models are commonly used to accomplish this task. Depending on these models to enact appropriate management plans assumes their accuracy, but most niche model studies do not provide validation for their model outputs. South Florida hosts the world's most globally diverse nonnative lizard community, providing a unique opportunity to evaluate the predictive ability of niche models by comparing model predictions to observed patterns of distribution, abundance and physiology in established non-native populations.Location: Florida, USA. Taxon: Lizards.Methods: Using Maxent, we developed niche models for all 29 non-native lizard species with established populations in Miami-Dade County, Florida, using native range data to predict habitat suitability in the invaded range. We then used independently collected field data on abundance, geographical spread and thermal tolerances of the non-native populations to evaluate Maxent's ability to make predictions in both geographical and environmental space in the non-native range.Results: Maxent performed well in predicting across geographical space where these non-native lizards were most likely to occur, but within a given geographical extent was unable to predict which individual species would be the most abundant or widespread. Comparisons with physiological data also revealed an imperfect fit, but without any consistent biases. Main conclusions:We performed one of the most extensive field validations of Maxent's ability to predict where invasions are likely to occur, and our results support its continued use in this role. However, the program was unable to predict the relative abundance and geographical spread of established species, indicating limited utility for identifying which invasive species will be the greatest management concern. These results underscore the importance of other factors, such as time since introduction, dispersal ability and biotic interactions in determining the relative success of non-native species post-establishment. K E Y W O R D S biological invasions, climate suitability, ecological niche model, lizards, Maxent, model validation, non-native species, thermal tolerance

Pastureland currently occupies 26% of Earth's ice-free land surface. As the global human population continues to increase and developing countries consume more proteinrich diets, the amount of land devoted to livestock grazing will only continue to rise. To mitigate the loss of global biodiversity as a consequence of the ever-expanding amount of land converted from native habitat into pastureland for livestock grazing, an understanding of how livestock impact wildlife is critical. While previous reviews have examined the impact of livestock on a wide variety of taxa, there have been no reviews examining how global livestock grazing affects amphibians. We conducted both an empirical study in south-central Florida examining the impact of cattle on amphibian communities and a quantitative literature review of similar studies on five continents. Our empirical study analyzed amphibian community responses to cattle as both a binary (presence/absence) variable, and as a continuous variable based on cow pie density. Across all analyses, we were unable to find any evidence that cattle affected the amphibian community at our study site. The literature review returned 46 papers that met our criteria for inclusion. Of these studies, 15 found positive effects of livestock on amphibians, 21 found neutral/mixed effects, and 10 found negative effects. Our quantitative analysis of these data indicates that amphibian species that historically occurred in closedcanopy habitats are generally negatively affected by livestock presence. In contrast, opencanopy amphibians are likely to experience positive effects from the presence of livestock, and these positive effects are most likely to occur in locations with cooler climates and/or greater precipitation seasonality. Collectively, our empirical work and literature review demonstrate that under the correct conditions well-managed rangelands are able to support diverse assemblages of amphibians. These rangeland ecosystems may play a critical role in protecting future amphibian biodiversity by serving as an "off-reserve" system to supplement the biodiversity conserved within traditional protected areas.

Extreme climate events are predicted to increase in frequency and severity due to contemporary climate change. Recent studies have documented the evolutionary impacts of extreme events on single species, but no studies have yet investigated whether such events can drive community-wide patterns of trait shifts. On 22 January 2020, subtropical south Florida experienced an extreme cold episode during which air temperatures dropped below the lower thermal limit of resident lizard populations. In the week immediately after the cold event, we documented decreased lower thermal limits (CT min ) of six co-occurring lizard species that vary widely in ecology, body size and thermal physiology. Although cold tolerance of these species differed significantly before the cold snap, lizards sampled immediately after had converged on the same new, lower limit of thermal tolerance. Here, we demonstrate that extreme climate events can drive substantial and synchronous community-wide trait changes and provide evidence that tropical and subtropical ectotherms—often characterized as unable to withstand rapid changes in climatic conditions—can endure climatic conditions that exceed their physiological limits. Future studies investigating the mechanisms driving these trait shifts will prove valuable in understanding the ability of ectotherm communities to mitigate climate change.

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Standardized classification methods based on quantifiable risk metrics are critical for evaluating extinction threats because they increase objectivity, consistency, and transparency of listing decisions. Yet, in the United States, neither federal nor state agencies use standardized methods for listing species for legal protection, which could put listing decisions at odds with the magnitude of the risk. We used a recently developed set of quantitative risk metrics for California herpetofauna as a case study to highlight discrepancies in listing decisions made without standardized methods. We also combined such quantitative metrics with classification tree analysis to attempt to increase the transparency of previous listing decisions by identifying the criteria that had inherently been given the most weight. Federally listed herpetofauna in California scored significantly higher on the risk-metric spectrum than those not federally listed, whereas state-listed species did not score any higher than species that were not state listed. Based on classification trees, state endemism was the most important predictor of listing status at the state level and distribution trend (decline in a species' range size) and population trend (decline in a species' abundance at localized sites) were the most important predictors at the federal level. Our results emphasize the need for governing bodies to adopt standardized methods for assessing conservation risk that are based on quantitative criteria. Such methods allow decision makers to identify criteria inherently given the most weight in determining listing status, thus increasing the transparency of previous listing decisions, and produce an unbiased comparison of conservation threat across all species to promote consistency, efficiency, and effectiveness of the listing process. Article impact statement: Using standardized, quantitative methods to assess extinction risk can improve listing decisions by increasing consistency and transparency