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Amphibians are more threatened than any other vertebrate class, yet evidence for many threats is missing. The Cape lowland fynbos (endemic scrub biome) is threatened by habitat loss, and natural temporary freshwater habitats are removed in favour of permanent impoundments. In this study, we determine amphibian assemblages across different freshwater habitat types with special attention to the presence of invasive fish. We find that anuran communities differ primarily by habitat type, with permanent water habitats having more widespread taxa, while temporary water bodies have more range restricted taxa. Invasive fish are found to have a significant impact on frogs with toads most tolerant of their presence. Temporary freshwater habitats are a conservation priority in the area, and their amphibian assemblages represent endemic taxa that are intolerant of invasive fish. Conservation of a biodiverse amphibian assemblage in lowland fynbos areas will rely on the creation of temporary freshwater habitats, rather than a northern hemisphere pond based solution. [ABSTRACT FROM AUTHOR]

The study of the environmental features affecting amphibian communities is a priority task for addressing effective conservation initiatives. In the southern edge of the Apennines (Sila Massif, Calabria Region, Italy), we surveyed the distribution of amphibians in lotic freshwater habitats (eight rivers, 17 sampling stations, 87 transects) and recorded nine environmental variables, including the occurrence of potential predators (fish and Eurasian otter Lutra lutra), potentially affecting the distribution and breeding success of amphibian species. A total of seven amphibian species was recorded (75.9% of transects). Fish occurred in all rivers while the otter was found in four rivers (Amato, Lese, Neto, and Savuto). Illuminance and bank heterogeneity were the main factors affecting amphibian reproduction, while neither otter nor fish presence showed significant effects on the amphibian community. Overall, habitat complexity and coevolution history seemed to shape the distribution of amphibians and their breeding sites, while the ongoing recolonization of the study area by the otter is expected to have a negligible impact on the richness of the amphibian community. [ABSTRACT FROM AUTHOR]

Metacommunity ecology provides a basis for understanding how ecological communities are assembled. Metacommunity theory can be applied to assess the effects of anthropogenic disturbance on freshwater communities. However, few studies have examined how species-specific responses to environmental covariates can generate broader patterns in freshwater metacommunities. I determined occupancy patterns in an amphibian metacommunity to identify important predictors of reproduction at wetland sites. I conducted surveys at 49 wetlands for tadpoles with fish traps and dip netting in an urbanising region in southeastern Australia. The larvae of seven frog species were detected. There were negative relationships between the probabilities of reproduction at a site and the relative abundance of the eastern mosquitofish (Gambusia holbrooki) and wetland electrical conductivity. There was a positive relationship between tadpole occupancy and the proportion of accessible habitat within 1000 m of a site, a measure of the combined effects of roads and habitat amount. These results highlight the negative effect of predatory Gambusia on frog communities and illustrate the importance of the species-sorting and mass-effect perspectives of metacommunity theory at multiple spatial scales. Habitat restoration projects for amphibians should remove exotic fish or prevent their establishment in managed wetlands and maintain habitat connectivity to facilitate dispersal. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) have been reported to threaten a wide variety of terrestrial, marine, and freshwater organisms. However, knowledge about the effects of MPs on anuran amphibians, one of the most threatened taxa worldwide, is still limited. To assess the effects of MPs on the growth and survival of the Italian agile frog (Rana latastei) and green toad (Bufotes balearicus) , we exposed tadpoles to three different concentrations (1, 7, and 50 mg L−1) of an environmental relevant mixture of microplastics (HPDE, PVC, PS and PES), recording data on their activity level, weight and mortality rates. While the effects of MPs on green toad tadpoles were negligible, Italian agile frog tadpoles were severely affected both in terms of growth and activity level, with high mortality rates even at the lowest MP density (1 mg L−1). Our results suggest that MP contamination of freshwater habitats may contribute to the ongoing decline of anuran amphibians. [Display omitted] • Ingestion of polyester fibers affects the growth and survival of agile frog larvae. • Tadpole feeding efficiency is affected by direct damage or induced satiety. • Polymer type, particle size, morphology and color affect intake by anuran larvae. • Microplastic may contribute to the decline of vulnerable anuran species. [ABSTRACT FROM AUTHOR]