Spatial distribution and habitat selection by anurans in Atlantic Forest over Barreiras Formation in southeastern Brazil

Abstract

Some plants accumulate rainwater forming microenvironments to be used by amphibians. Bromeligenous frogs use these plants for reproductive purposes and bromelicolous frogs can use for refuge and foraging. The distribution of these animals as a grouped form added differences between occupied and unoccupied plants can evidence habitat selection. These possible selection can be related to the weight of the animals, under hypothesis that heavier males defend more complex plants. This behavior can be observed in bromeligenous, once defend breeding sites. This work aims study the spatial distribution pattern of the amphibian community in the occupation of plants, test for differences in the number of leaves and axils between occupied and unoccupied plants by P. luteolus, besides the relationship between these variables and the weight of this bromeligenous. Under the null hypothesis of the random or uniform distribution, no differences between occupied and unoccupied plants and no relation between weight, number of leaves and axils. The amphibians were sampled in one area of Vale Nature Reserve (RNV, due acronym in portuguese), Linhares-ES. Which was made a cartesian plane on the area and through active and listening search the animals were located and referenced in the respective plants in which they lived, which were also counted and identified. Were recorded four amphibians species (Phyllodytes luteolus, Scinax alter, Scinax argyreornatus and Trachycephalus mesophaeus) and five plants species containing water in RNV. The Poisson distribution (I) was differed among amphibians. Three amphibians species showed clumped distribution and only S. argyreornatus, distribution close to random. According to the χ²-test, the occupation of S. alter was proportional to the abundance of plants. Phyllodytes luteolus was only bromeligenous found and ,according to t-test, occupied organography more complex plants, as demonstrated in the correlation (rs), the occupancy was not correlated to the weight of the animals. The plant selection was not random and there are differences in the preference of the species, which can maintain coexistence in the community. The choice of a more complex organography can positively influence the survival and reproductive success of P. luteolus.