Onde cantam as pererecas: A influência da vegetação na seleção de habitat por Phyllomedusa iheringii (Anura: Phyllomedusidae)

Abstract

Local and landscape structural characteristics may have Strong influence on amphibians abundance and distribution. However, factors modeling habitat and microhabitat selection are unknown for most Neotropical anuran species. Phyllomedusa iheringii is a treefrog endemic to the Pampa biome, whose ecology remains poorly understood. Herein we analyzed spatial and micro spatial distribution of males in 12 ponds, monitored monthly across three breeding seasons, testing the hypothesis of the role of local and landscape variables on the distribution and abundance of P. iheringii. We georeferenced the occurrence of 256 individuals of P. iheringii along the monitored waterbodies We used multiple linear regressions to test the possible influence of environmental variables on the variation of abundance among the ponds. In addition, we used circular statistics (Rayleigh test) to test the null hypothesis of uniform distribution of individuals along the pond edges. Additionally, we employed the Spearman rank coefficient in order to test possible correlations of male calling site concentration with the vegetation type available (herbaceous and arboreal) at the pond edges or with the male abundance. Abundance of P. iheringii males increases in ponds with high percentage of arboreal vegetation. . Most ponds (54% of total) showed that calling sites were spatially concentrated at pond edges. However, P. iheringii concentration was not correlated with individual abundance or with the arboreal/herbaceous coverage percentage In this case, other factors related with lek maintenance, such as acoustic/calling site suitability or the characteristics of the vegetation available for oviposition, may be most suitable to explain observed patterns, and deserve future investigations.