Date of Award:

8-2015

Document Type:

Dissertation

Degree Name:

Doctor of Philosophy (PhD)

Department:

Wildland Resources

Advisor/Chair:

Karen H. Beard

Abstract

The Atlantic Forest extends mainly along the Atlantic coast of Brazil, but today the native habitat is reduced to 14.5% of its historical range. This biome is among the fifth most important biodiversity hotspots in the world due to the high richness and endemism and also high degree of human-induced habitat modification. Understanding the response of species with differing life-history traits to habitat modification such as forest edges and matrix types helps predict species occurrence across changing landscapes. Previous studies have used amphibians as a biological indicator of habitat quality due to their physiological and morphological constraints. Amphibians are also an excellent taxon model to study antipredator behavior due to their variety of defensive postures, vocalizations, skin secretions and aposematic colors. Brazil has currently 1026 recognized amphibian species, of which 60 species were described in the past five years, mostly from the Atlantic Forest biome. New species are increasingly described with the increase in sampling effort at microhabitats from remote areas. My study aimed to understand frog response to habitat modification and their antipredator behaviors, and also to describe a new frog species. First, I demonstrated that the breeding guild was the most important variable explaining frog response to edge effects and matrix types. Leaf-litter and bromeliad breeders decreased in richness and abundance from the forest interior toward the matrix habitats. Water-body breeders increased in richness toward the matrix and remained relatively stable in abundance across distances. Second, I created a database comprising 224 records of frog antipredator behavior, of which 102 (45%) were collected during our fieldwork, 116 (52%) were compiled from the literature, and six (3%) were reported by colleagues. The 224 records represented 165 species, and included 16 families of anurans. Lastly, I described the first bromeliad-dwelling species among the 96 species of the genus Dendropsophus. The new species was diagnosed by its small size, framed dorsal color pattern, medium-sized vocal sac, and short membrane in the fifth toe. Phylogenetic analysis based on molecular data indicated this new species should not be assigned to any of the currently recognized species groups of Dendropsophus.

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