Geographic and altitudinal distribution of the insular endemic frog Hylodes fredi (Anura: Hylodidae) of the Atlantic coast of southeastern Brazil

Autor: Helena Godoy Bergallo, Caroline Nogueira Conde Reis, Tatiana Motta-Tavares, Carlos Frederico Duarte Rocha
Rok vydání: 2019
Předmět:
Zdroj: Journal of Coastal Conservation. 23:615-621
ISSN: 1874-7841
1400-0350
Popis: Our main goal was to understand the distribution across the horizontal (coordinates) and vertical (altitude) space of the island endemic stream dwelling anura Hylodes fredi, in order to improve strategies for its conservation. We conducted auditory and visual surveys along trails and streams in Ilha Grande (an Atlantic forested island in southeast Brazil, the only place where the species occurs), to estimate the frequency of occurrence and the density of H. fredi between the island slopes (according to the ridgeline which crosses the island from east to west) and along the streams. Hylodes fredi was detected in 31.5% of the streams sampled, occurring only in forested localities. We did not record H. fredi in streams with any sort of human disturbance (like buildings, pollution and/or pipes). Hylodes fredi had a higher frequency of occurrence in streams of the oceanic slope (42.6%) than in continental slope (23.1%), probably due to the higher levels of precipitation in this slope together with the reduced levels of human occupation in comparison with the continental slope. We found an overall average density of 0.04 individuals per meter of stream, possibly because of its territorial behaviour and specific habitat requirements. The distribution of H. fredi along the island is probably consequence of the species’ restrict habitat requirement, together with a possible negative impact of human occupation in lower altitudes.
Databáze: OpenAIRE
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