Anurofauna of an Atlantic Rainforest fragment and its surroundings in Northern Rio de Janeiro State, Brazil

Abstract

We carried out a study on the anurofaunal community from an Atlantic Forest fragment (Monte Verde mountains) and the surrounding area in Cambuci municipality, Rio de Janeiro State, Brazil, which constitutes one of the largest fragments remaining in the largely deforested landscape of the northern portion of the State. We combined three sampling methods: plot sampling, transects and pit-fall traps. We recorded twenty species of amphibians, of which only eleven were found within the forest fragment (and five of these also occurred in the surrounding matrix). Two of the species recorded in the present study (Crossodactylus sp. and Ischnocnema cf. parva) may represent undescribed taxa. Our records expand the distribution range of one species (Scinax trapicheiroi) to the north, and fill a geographic distribution gap for another one (Ischnocnema oea). The estimated overall density of frogs living in the leaf litter of the fragment (based on results of plot sampling) was 3.1 individuals/100 m², with Haddadus binotatus being the most abundant species (2.4 individuals/100 m²). Comparisons of our data with those of other studies suggest that anuran communities in forest fragments ca. 1,000 ha or smaller may be severely limited in their richness, and often include a large proportion of species tolerant to open areas, such as many hylids. Our results show the importance of increasing knowledge about the anurofaunal community of the northern portion of the State of Rio de Janeiro and preserve the forest remnants that still exist in the region.

Species composition and density estimates of the anurofauna of a site within the northernmost large Atlantic Forest remnant (Parque Estadual do Desengano) in the state of Rio de Janeiro, Brazil

“…In that study, using the same sampling methods that we used in the present one, 20 species of frogs were recorded. Nevertheless, only 11 species (or 55% of the species sampled) were found within the forest fragment, with the remaining ones being associated with open and disturbed habitats at its border or in the surrounding matrix (Almeida-Gomes et al 2010). In the present study we recorded a similar number of species (13) using a similar sampling effort, but the PED has a much larger and less disturbed forest area when compared to the fragment studied in Cambuci.…”

“…, and of anuran amphibians in a small fragment in Cambuci municipality (Almeida-Gomes et al 2010). Most studies about anuran amphibian assemblages/guilds in forested areas of Rio de Janeiro have been conducted in the central and southern portions of the state (e.g.…”

Anuran species of the Salto Morato Nature Reserve in Paraná, southern Brazil: review of the species list

“…As in many other areas of the Atlantic Forest (e.g., Conte and Rossa-Feres 2006;Bertoluci et al 2007;Carvalho-e-Silva et al 2008;Almeida-Gomes et al 2010), the Hylidae was the most species diverse frog family in the SMNR. Most of the species were arboreal, and reproduce by mode 1 (eggs and tadpoles deposited in standing water).…”

Differential success in sampling of Atlantic Forest amphibians among different periods of the day

“…In the Neotropics, VES and plots are the methods that have been the most successful during short-term anuran surveys, for both total abundance and species richness (e.g. Doan, 2003;Almeida-Gomes et al, 2008, 2010Siqueira et al, 2009). However, studies conducted at different times of day in some areas show that capture success is not equal throughout the day, being the highest during the night (e.g.…”

“…However, this type of inference has its limitations, since not all the frogs may actually be active at the moment of encounter. Nevertheless, this approach has been used in studies of anuran assemblages/guilds in Atlantic (Rocha et al, 2000Almeida-Gomes et al, 2008, 2010Siqueira et al, 2009) and Amazonian rainforests (Menin et al, 2008) in Brazil. In two studies (Rocha et al, 2000;Menin et al, 2008) a similar proportion of individuals (ca.…”