Fernando Rodrigues da Silva

Uso de fragmentos florestais por anuros (Amphibia) de área aberta na região noroeste do Estado de São Paulo

Silva, F.R. and Rossa-Feres, D.C. The use of forest fragments by open-area anurans (Amphibia) in northwestern Sao Paulo State, Brazil Biota Neotrop. May/Aug 2007 vol. 7, no. 2. http://www.biotaneotropica. org.br/v7n2/pt/abstract?article+bn03707022007. ISSN 1676-0603. Landscape arrangement plays a key role in community structure and composition. Our study was based on the hypothesis that forest fragments work as shelter areas for open-area anuran species. Four forest fragments were studied in the municipality of Icem, northwestern Sao Paulo State; the fragments were 1 to 4 km apart from each other. The anurans were sampled in the fragments by pitfalls, artificial shelters, and active search. Twelve species were registered (48% of the species known for the region); three of these species (Eupemphix nattereri, Leptodactylus podicipinus, and Physalaemus cuvieri) had high abundance (n > 50 individuals). In the pitfalls, 228 individuals belonging to 10 anuran species were captured. The high richness and abundance of specimens captured mean that forest fragments are important components for the anuran communities. Forest fragments in the Icem region can be used by anurans in three non-exclusive ways: i) as shelter areas during the dry season (five species registered); ii) as day shelters during the anuran reproductive season (six species registered in artificial shelters during the day, throughout the rainy season); and iii) as foraging areas (one specimen of Leptodactylus podicipinus found feeding on Blattaria in the fragment FM2). Therefore, the preservation of anuran populations of open habitats depends, to the same extent, on terrestrial habitats, such as forest fragments, and on the ponds where they reproduce.

Dependence of anuran diversity on environmental descriptors in farmland ponds

In the Neotropics, conversion of natural habitats into agricultural areas is occurring at a high rate, with consequent reduction of habitat complexity in anuran breeding ponds. Identifying features of farmland ponds that allow them to support a high diversity of species is fundamental for successful management and conservation policies and is especially important in Neotropical regions that harbor the highest anuran species richness in the world. Here, we aimed to investigate which environmental descriptors correlate the occurrence of anuran species in tropical farmland ponds in southeastern Brazil. We found that environmental descriptors reflecting the complexity of vegetation in farmland ponds primarily predict the diversity of anuran species in these habitats. Species richness was correlated mainly by vegetation height in the margin, with ponds that exhibit greater stratification harboring a larger number of species. Vegetation height in the interior of ponds, diversity of vegetation in the margin, pond area and hydroperiod were also important variables predicting the abundance of six of 10 anuran species analyzed. Our results show that features of farmland ponds representing increased habitat complexity are key factors in maintaining a high diversity of species, providing a greater variety of microhabitats, both in vertical and horizontal strata, and thus meeting diverse species-specific requirements.

Biogeographic Distribution Patterns and Their Correlates in the Diverse Frog Fauna of the Atlantic Forest Hotspot

Anurans are a highly diverse group in the Atlantic Forest hotspot (AF), yet distribution patterns and species richness gradients are not randomly distributed throughout the biome. Thus, we explore how anuran species are distributed in this complex and biodiverse hotspot, and hypothesize that this group can be distinguished by different cohesive regions. We used range maps of 497 species to obtain a presence/absence data grid, resolved to 50×50 km grain size, which was submitted to k-means clustering with v-fold cross-validation to determine the biogeographic regions. We also explored the extent to which current environmental variables, topography, and floristic structure of the AF are expected to identify the cluster patterns recognized by the k-means clustering. The biogeographic patterns found for amphibians are broadly congruent with ecoregions identified in the AF, but their edges, and sometimes the whole extent of some clusters, present much less resolved pattern compared to previous classification. We also identified that climate, topography, and vegetation structure of the AF explained a high percentage of variance of the cluster patterns identified, but the magnitude of the regression coefficients shifted regarding their importance in explaining the variance for each cluster. Specifically, we propose that the anuran fauna of the AF can be split into four biogeographic regions: a) less diverse and widely-ranged species that predominantly occur in the inland semideciduous forests; b) northern small-ranged species that presumably evolved within the Pleistocene forest refugia; c) highly diverse and small-ranged species from the southeastern Brazilian mountain chain and its adjacent semideciduous forest; and d) southern species from the Araucaria forest. Finally, the high congruence among the cluster patterns and previous eco-regions identified for the AF suggests that preserving the underlying habitat structure helps to preserve the historical and ecological signals that underlie the geographic distribution of AF anurans.

Influence of terrestrial habitat isolation on the diversity and temporal distribution of anurans in an agricultural landscape

Discontinuity between suitable aquatic and terrestrial habitats forces many amphibian species with aquatic larvae to undertake risky breeding migrations through disturbed environments, potentially contributing to population declines by reducing survival of adults and juveniles (Becker et al . 2007). The north-western region of the state of Sao Paulo, Brazil, is characterized by fragments of mesophytic semideciduous forest and savanna, surrounded by a matrix of pasture, plantations and urban areas with only 4% of the remaining original vegetation of the state (Ribeiro et al . 2009). Currently, 36 anuran species have been recorded in this region, corresponding to almost 15% of the states species (Araujo et al . 2009). The anuran species of this region are associated with open environments or are widely distributed in the different Brazilian biomes (Duellman 1999). Silva & Rossa-Feres (2007) showed the importance of forest fragments in this region for 12 anuran species that breed in pools located in a pasture matrix.

Value of Small Forest Fragments to Amphibians

Univ Estadual Paulista, UNESP, Dept Bot & Zool, BR-15054000 Sao Jose do Rio Preto, SP, Brazil

Amphibia, Anura, Hylidae, Dendropsophus melanargyreus (Cope, 1887): distribution extension, new state record and geographic distribution map

We present the first record of Dendropsophus melanargyreus for the state of Sao Paulo and a distribution map for this species. This new record represents the southeastern limit of distribution, which is 106 Km from the nearest locality previously recorded for this species and is the fourth new register of anuran to northwestern region of Sao Paulo in the last two years, increasing species list of the region from 33 to 36 species. This results evidence the importance of this region as priority area for inventory.

Amphibian Beta Diversity in the Brazilian Atlantic Forest: Contrasting the Roles of Historical Events and Contemporary Conditions at Different Spatial Scales

Current patterns of biodiversity distribution result from a combination of historical and contemporary processes. Here, we compiled checklists of amphibian species to assess the roles of long-term climate stability (Quaternary oscillations), contemporary environmental gradients and geographical distance as determinants of change in amphibian taxonomic and phylogenetic composition in the Brazilian Atlantic Forest. We calculated beta diversity as both variation in species composition (CBD) and phylogenetic differentiation (PBD) among the assemblages. In both cases, overall beta diversity was partitioned into two basic components: species replacement and difference in species richness. Our results suggest that the CBD and PBD of amphibians are determined by spatial turnover. Geographical distance, current environmental gradients and long-term climatic conditions were complementary predictors of the variation in CBD and PBD of amphibian species. Furthermore, the turnover components between sites from different regions and between sites within the stable region were greater than between sites within the unstable region. On the other hand, the proportion of beta-diversity due to species richness difference for both CBD and PBD was higher between sites in the unstable region than between sites in the stable region. The high turnover components from CBD and PBD between sites in unstable vs stable regions suggest that these distinct regions have different biogeographic histories. Sites in the stable region shared distinct clades that might have led to greater diversity, whereas sites in the unstable region shared close relatives. Taken together, these results indicate that speciation, environmental filtering and limited dispersal are complementary drivers of beta-diversity of amphibian assemblages in the Brazilian Atlantic Forest.

EVALUATION OF SURVEY METHODS FOR SAMPLING ANURAN SPECIES RICHNESS IN THE NEOTROPICS

ABSTRACT. Species richness is central to ecological theory, with practical applications in conservation, environmental management and monitoring. Several techniques are available for measuring species richness and composition of amphibians in breeding pools, but the relative efficacy of these methods for sampling high-diversity Neotropical amphibian fauna is poorly understood. I evaluated seven studies from south and south-eastern Brazil to compare the relative and combined effectiveness of two methods for measuring species richness at anuran breeding pools: acoustic surveys with visual encounter of adults and dipnet surveys of larvae. I also compared the relative efficacy of each survey method in detecting species with different reproductive modes. Results showed that both survey methods underestimated the number of species when used separately; however, a close approximation of the actual number of species in each breeding pool was obtained when the methods were combined. There was no difference between survey methods in detecting species with different reproductive modes. These results indicate that researchers should employ multiple survey methods that target both adult and larval life history stages in order to accurately assess anuran species richness at breeding pools in the Neotropics.

Anura, Estação Ecológica de Jataí, São Paulo state, southeastern Brazil

Universidade Estadual Paulista (UNESP), Campus de Sao Jose do Rio Preto, Departamento de Zoologia e Botanica, Rua Cristovao Colombo, 2265, Jd. Nazareth, CEP 15054-000, Sao Jose do Rio Preto, SP, Brazil

Anuran captured in pitfall traps in three agrossystem in Northwestern São Paulo State, Brazil

Although it is generally assumed that agriculture negatively influences amphibian populations, few studies on the effects of agricultural cultivations on neotropical anuran have been conducted. As a contribution to the knowledge about anuran in agriculture, the present study sought to identify the anuran species present in three different agrossystems. We used data from anurans captured in pitfall traps initially proposed for a survey of harvestmen fauna in three agrossystems (corn, soybean, and rubber tree). Four anuran species found in the pitfall traps belong to two Families: Leptodactylidae: Leptodactulus fuscus and L. mystacinus; and Leiuperidae: Eupemphix nattereri and Physalaemus cuvieri. In corn plantation, four species and 30 individuals were captured; in rubber trees, four species and 11 individuals; and in soybeans plantation, tree species and eight individuals. Our results show that anurans are present in agrossystems, mainly the generalist anuran species.