The frogs of the family Ceratophryidae (comprised of three genera containing 12 species) are well known for their voracious feeding behavior and unique morphologies in both larval and post-metamorphic life stages. Nevertheless, relatively little is known about the diet of these species, especially in nature. We summarized the current knowledge of the diet of larval and post-metamorphic ceratophryids in both natural and experimental settings by conducting a literature review, specimen dissections, and field observations. Prior to this study, diet information did not exist for one fourth of the species in the family: Ceratophrys calcarata, Ceratophrys joazeirensis Ceratophrys stolzmanni, and Ceratophrys testudo. We add, for the first time, information on the diet of Ceratophrys calcarata. In addition, our survey revealed that relatively few detailed studies with large sample sizes have been conducted on the diet of these frogs. Frequently, knowledge of the diet of a species is derived from palatability experiments using captive individuals (often a single individual). From those diet studies that were conducted under natural conditions, ceratophryids can be classified as generalist, opportunistic predators, often preying on a wide variety of invertebrate and vertebrate prey. All species of ceratophryids for which we obtained information on diet were found to consume vertebrates, with anuran prey occurring in nearly all species. Even less is known about the diet of the tadpoles of these species; while cannibalism is assumed to be widespread, we found evidence for cannibalism at the larval stage in only three species. Future studies should attempt to understand the trophic ecology of these species under natural scenarios at both life stages, and an ontogenetic approach using individuals across multiple size classes could elucidate the niche shifts associated with these species from larva to adult.

Temporal variation represents an important component in understanding the structure of ecological communities and species coexistence. We examined calling phenology of an assemblage of anurans in the Gran Chaco ecoregion of Bolivia by deploying automated recording devices to document nocturnally vocalizing amphibians nightly at seven ponds from 20 January 2011 until 31 October 2011. Using logistic regression, we modelled the relationships between temperature, rainfall and photoperiod with calling activity. There was a distinct seasonal effect with calling activity concentrated in the rainy season with no species detected during the dry season from June until the end of October. Calling activity was positively and significantly correlated with photoperiod in 9 of the 10 species analyzed, but there were distinct species-specific relationships associated with rainfall and temperature. All of these species utilize ephemeral ponds as breeding sites, which can account for their reliance on rainfall as an important driver in calling activity. Two prolonged breeders exhibited similar seasonal breeding patterns across the rainy season, but differed in their response to daily abiotic factors, which might be attributed to the constraints imposed by their reproductive mode. Explosive breeders needed several days of rain to elicit calling. Two pairs of congeners had distinct species-specific relationships between their calling activity and abiotic factors, even though the congeners shared the same reproductive mode, suggesting that the reproductive modes vary in the constraints imposed on calling activity. The patterns observed suggest that calling phenology of tropical anurans is determined by the interaction of exogenous factors (i.e. climatic variables) and endogenous factors (i.e. reproductive modes).

Summary Freshwater pond communities exhibit strong patterns in species composition in response to environmental gradients such as ecosystem size, disturbance and productivity, serving as excellent systems for studies of food‐web structure. We surveyed 13 ponds that varied along environmental gradients of canopy cover, pond size and hydroperiod at the beginning and end of the rainy season in the semi‐arid thorn forests of the Gran Chaco ecoregion of Bolivia. We collected basal resources and consumers (tadpoles, macroinvertebrates and fishes) from these ponds and used stable isotope ratios of carbon (13C/12C) and nitrogen (15N/14N), to quantify the spatiotemporal dynamics of the food webs in these tropical ponds. There were no relationships between vertical structure of the food webs and the environmental gradients associated with the ponds. Consumers within these ponds exhibited high trophic variability, with multiple taxa occupying more than one trophic position across space or time. Consumers from larger ponds had a greater degree of trophic redundancy. More shaded ponds supported food webs that had lower trophic diversity. More permanent ponds had significantly greater trophic diversity as well as a greater range of basal resource diversity. The breeding ponds utilised by tadpoles and macroinvertebrates are patchily distributed across space and time. In these dynamic habitats, a feeding strategy of trophic generalism and plasticity enables consumers to exploit a broad range of resources and promote species coexistence. These results suggest that high diversity in tropical ponds does not necessarily translate into specialisation of trophic function.

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Tadpoles are diverse and abundant consumers, and knowledge of their feeding ecology and trophic status is essential in understanding their functional roles within aquatic habitats. Here we revisit Altig, Whiles, and Taylor (2007)'s paper, which highlighted the knowledge gaps in tadpole feeding ecology and the application of modern techniques, such as stable isotope and fatty acid analyses to better quantify dominant food resources, food assimilation, and the trophic status of tadpoles. We reviewed the ecological studies that have been published since 2007 that used stable isotopes and fatty acid analyses, also metagenomics and ecological stoichiometry analyses. We describe the ecological roles of tadpoles in freshwater ecosystems and identify knowledge gaps regarding tadpole feeding ecology across biogeographic regions. Worldwide declines in amphibian abundance and diversity create an urgent need to document their feeding ecology and trophic status. As consumers, tadpoles play important functional roles in nutrient cycling, energy flow, and bioturbation. They also exhibit context‐dependent trophic plasticity in response to abiotic and biotic gradients, which complicates understanding of their trophic roles. Most studies of tadpole trophic ecology have been conducted primarily on species from the families Ranidae, Bufonidae, and Hylidae from Neotropic and Nearctic regions, while species in tropical regions such as Africa and Asia lack ecological information for tadpoles. There continues to be a need for studies of tadpole diets and/or trophic ecology in Africa and Southeast Asia regions where species endemism is threated by the growth of anthropogenic activities. The majority of studies have focused on trophic ecology of tadpoles from the perspective of single species or at relatively small spatial and temporal scales. Studies that address questions from an ecosystem perspective were scarce, but are critical for conservation and management. Future research should aim to address the role of tadpoles as consumers across broader spatiotemporal scales.

Animal road mortality is the product of multiple factors. We sought to examine the impact of roads on Bolivian biodiversity by quantifying road mortality in a community of tropical snakes and examine variation in road-kills in the context of extrinsic (seasonal effects) and intrinsic factors (habitat guild, sex). From 2007 to 2011, we surveyed the old Santa Cruz-Cochabamba highway and local dirt roads in Florida Province, Santa Cruz Department, Bolivia. We observed 1,444 snake road-kills comprised at least 32 species from 21 genera and 4 families. Nearly one fifth (18.4%) of road-killed species are endemic to the region. A temporal peak in road mortality was observed in February in the middle of the rainy season and was lowest in July coinciding with the dry season. Male snakes were more frequently killed than females and male mortality peaked during the mid to late rainy season. Habitat guild had a significant influence on the species occurrence during the road surveys; roadkills of terrestrial snakes were observed more frequently compared with fossorial, arboreal, semi-arboreal, and semi-aquatic species. The impact of roads on Bolivian biodiversity, including snakes, is expected to increase, as road networks in the region continue to expand. Documenting additional interspecific and intraspecific variation in vulnerabilities to road mortality is needed to better understand the long-term impacts of roads on population persistence as well as inform the design and implementation of mitigation efforts.

Description Functions to implement model selection and multimodel inference based on Akaike's information criterion (AIC) and the second-order AIC (AICc), as well as their quasilikelihood counterparts (QAIC, QAICc) from various model object classes. The package implements classic model averaging for a given parameter of interest or predicted values, as well as a shrinkage version of model averaging parameter estimates or effect sizes. The package includes diagnostics and goodness-of-fit statistics for certain model types including those of 'unmarkedFit' classes estimating demographic parameters after accounting for imperfect detection probabilities. Some functions also allow the creation of model selection tables for Bayesian models of the 'bugs' and 'rjags' classes. Functions also implement model selection using BIC. Objects following model selection and multimodel inference can be formatted to LaTeX using 'xtable' methods included in the package.

With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14‐week period (17 August–24 November of 2019). We sampled wildlife at 1,509 camera trap sites from 110 camera trap arrays covering 12 different ecoregions across four development zones. This effort resulted in 166,036 unique detections of 83 species of mammals and 17 species of birds. All images were processed through the Smithsonian’s eMammal camera trap data repository and included an expert review phase to ensure taxonomic accuracy of data, resulting in each picture being reviewed at least twice. The results represent a timely and standardized camera trap survey of the United States. All of the 2019 survey data are made available herein. We are currently repeating surveys in fall 2020, opening up the opportunity to other institutions and cooperators to expand coverage of all the urban–wild gradients and ecophysiographic regions of the country. Future data will be available as the database is updated at eMammal.si.edu/snapshot‐usa, as will future data paper submissions. These data will be useful for local and macroecological research including the examination of community assembly, effects of environmental and anthropogenic landscape variables, effects of fragmentation and extinction debt dynamics, as well as species‐specific population dynamics and conservation action plans. There are no copyright restrictions; please cite this paper when using the data for publication.