Diversity and Abundance of Litter Frogs in a Montane Forest of Southeastern Brazil: Seasonal and Altitudinal Changes¹

Abstract

We sampled litter frogs in an 1800-ha mid-elevation seasonal forest in southeastern Brazil. One hundred 8 X 8-m plots were sampled during the dryicold season and wetiwarm season (unburned areas); we also examined the effects of fire in recently burned areas. A total of 267 frogs (305 g), belonging to 16 species (4 families) were caught. A single species comprised 78.5 percent of the individuals in the dryicold season and 54.3 percent in the wetiwarm season. The density of individuals did not change significantly with season, biomass did. Density and biomass of frog5 were positively correlated with altitude. A Mantel test indicated that biological data (species and their abundance) were significantly associated with environmental parameters. The burned areas showed low values in richness, density and biomass of frogs. Harsh seasonal climate and a history of human disturbance may produce the low observed diversity values. The greater densities of frogs in sites of higher elevation may primarily result from mist-generated humidity, which diminishes the harshness of the dryicold season in relation to lower sites.

Species richness, relative abundance, and habitat of reproduction of terrestrial frogs in the Triângulo Mineiro region, Cerrado biome, southeastern Brazil

“…High values of dominance, such as those found for P. cuvieri at Uberlândia are typical of seasonally stressed environments, as found in other frog species communities (GIARETTA et al, 1997(GIARETTA et al, , 1999. Our results did not support the expected inverse correlation between specific abundance and body size (DINIZ-FILHO et al, 2004).…”

“…Differences among localities may in part also be attributed to the sampling effort, and to the degree of human disturbance, since around human settlements the presence of ponds and lakes may allow greater population densities of those species that otherwise would occur in undetectable densities. The expected decrease in species richness of frogs with increasing altitude (FAUTH et al, 1989;GIARETTA et al, 1999) may also play a role within the Cerrado biome. Keeping in mind the problems regarding taxonomic resolution, the estimated number of shared species (terrestrial frogs) between the Triângulo Mineiro and other localities varied from 11 (Serra da Canastra, HADDAD et al, 1988) to 15 (Brasília).…”

“…However, the number of terrestrial frogs found in the Triângulo Mineiro was similar (Boracéia, São Paulo, ca. 29 spp;HEYER et al, 1990) or even larger (GIARETTA et al, 1997(GIARETTA et al, , 1999 than forested localities in southeastern Brazil. Our results call attention to the possibility that the distinguishable rich terrestrial frog fauna of the Atlantic Forest (e. g. Boracéia, HEYER et al, 1990) is due to a disproportional contribution of its riparian species.…”

Herpetofauna of an Atlantic rainforest area (Morro São João) in Rio de Janeiro State, Brazil

“…In their study of leaf-litter anurofauna of an Atlantic forest area in São Paulo State, Giaretta et al (1999) calculated density values only for frogs, but mentioned that two reptiles (one lizard and one snake) were also found in plots. As the total area sampled in their study was 6400 m 2 , the local reptile density can thus be estimated at 0.03/100 m 2 and the lizard density at 0.015/100 m 2 , which is considerably lower than the value reported in the present study (0.8/100 m 2 ).…”

Patterns of parasitism by Amblyomma rotundatum (Ixodidae) on Rhinella schneideri (Bufonidae) in islands of São Francisco River, Minas Gerais, Brazil

“…It is well known that toads increase foraging activity in the wet season (Giaretta et al 1999) which may favors encounters with ticks.…”