Anurans of the Serra do Caraça, southeastern Brazil: species composition and phenological patterns of calling activity

Annual patterns of calling and breeding activity of 38 anuran species were studied at Serra do Caraça, an 11,233 ha reserve located in a contact zone between Cerrado and Atlantic forest at the southern Espinhaço range, southeastern Brazil. Five patterns were evident: (1) species that call year-round or nearly year-round with larger aggregations generally observed in the rainy months, (2) species with opportunistic calling activity associated with rainfall during the wettest months of the year, (3) winter species, (4) explosive breeders with intense calling activity triggered by heavy rains during the rainy season or only in the beginning of the rainy season, and (5) summer species with variable breeding seasons. Both the monthly number of species with calling males and the monthly number of species that showed the maximum class of calling males were positively correlated with both mean monthly temperature and monthly precipitation.

Calling activity and vocal repertoire of hypsiboas prasinus (Anura, Hylidae), a treefrog from the Atlantic Forest of Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Energy substrate utilization during nightly vocal activity in three species of Scinax (Anura/Hylidae)

Anuran amphibians exhibit different patterns of energy substrate utilization that correlate with the intensity of vocal and locomotor activities. Given the remarkable differences among species in breeding and feeding strategies, and the different ways energy is used in the whole animal, the suggested correlations between calling and locomotor behavior and the level of energy substrates in the muscles responsible for such activities are more complex than previously reported. We explored the relationships between calling and locomotor behavior and energy supply to trunk and hindlimb muscles, respectively, within the ecologically diverse tree-frog genus Scinax. Specifically, we measured the relative amount of carbohydrates and lipids in these two groups of muscles, and in the liver of three species of Scinax that differ in vocal and locomotor performance, and compared our results with those of two other species for which comparable data are available. We also compared the contents of lipids and carbohydrates of conspecific males collected at the beginning and after 4 h of calling activity. The stomach content to potential feeding opportunities across species was also assessed in both groups of males. Scinax hiemalis and S. rizibilis exhibit comparatively low and episodic calling during long periods of activity whereas S. crospedospilus calls at higher rates over shorter periods. Male S. hiemalis had highest levels of trunk muscle glycogen followed by those of S. rizilbilis and S. crospedospilus, respectively. There was no correlation between total lipid content in trunk muscle and calling rate among different species, suggesting that other metabolic aspects may be responsible for the energetic support for vocal activity. The levels of lipids and carbohydrates in trunk and hindlimb muscles and liver of males collected at the beginning and 4 h into the calling period were similar across species, so the extent of energetic reserves does not appear to constrain vocal or locomotor activity. Finally, we found exceptionally high levels of carbohydrates and lipids in the liver of S. rizibilis, a trait perhaps related to a long and demanding breeding period.

Advertisement call, vocal activity, and geographic distribution of Brachycephalus hermogenesi (Giaretta and Sawaya, 1998) (Anura, Brachycephalidae)

Brachycephalus hermogenesi is an endemic leaf litter inhabitant of the Atlantic forest of southeastern Brazil, whose original distribution included a restricted area near the boundaries of the States of Sao Paulo and Rio de Janeiro. We were surprised to find out, while conducting herpetofaunal surveys at Estacao Biologica de Boraceia (EBB), that the background forest insect-like sound we have been searching for corresponded to calling individuals of the species. Males call during the day at high densities, hidden under the leaf litter. Individuals do not answer playback, seem to move very infrequently, and seem to ignore nearby calling activity. We gathered data on annual and daily vocal activity of the species at EBB, observing a total of 1,549 calls given by 31 focal individuals in November 2003 and 2005. The call varies from short single note calls to calls composed of groups of two to seven similar notes emitted at regular intervals. We also extend the known distribution of the species southward to the State of Sao Paulo.

Energy substrate utilization during nightly vocal activity in three species of Scinax (Anura/Hylidae)

Anuran amphibians exhibit different patterns of energy substrate utilization that correlate with the intensity of vocal and locomotor activities. Given the remarkable differences among species in breeding and feeding strategies, and the different ways energy is used in the whole animal, the suggested correlations between calling and locomotor behavior and the level of energy substrates in the muscles responsible for such activities are more complex than previously reported. We explored the relationships between calling and locomotor behavior and energy supply to trunk and hindlimb muscles, respectively, within the ecologically diverse tree-frog genus Scinax. Specifically, we measured the relative amount of carbohydrates and lipids in these two groups of muscles, and in the liver of three species of Scinax that differ in vocal and locomotor performance, and compared our results with those of two other species for which comparable data are available. We also compared the contents of lipids and carbohydrates of conspecific males collected at the beginning and after 4 h of calling activity. The stomach content to potential feeding opportunities across species was also assessed in both groups of males. Scinax hiemalis and S. rizibilis exhibit comparatively low and episodic calling during long periods of activity whereas S. crospedospilus calls at higher rates over shorter periods. Male S. hiemalis had highest levels of trunk muscle glycogen followed by those of S. rizilbilis and S. crospedospilus, respectively. There was no correlation between total lipid content in trunk muscle and calling rate among different species, suggesting that other metabolic aspects may be responsible for the energetic support for vocal activity. The levels of lipids and carbohydrates in trunk and hindlimb muscles and liver of males collected at the beginning and 4 h into the calling period were similar across species, so the extent of energetic reserves does not appear to constrain vocal or locomotor activity. Finally, we found exceptionally high levels of carbohydrates and lipids in the liver of S. rizibilis, a trait perhaps related to a long and demanding breeding period.

Advertisement call of Scinax littoralis and S. angrensis (Amphibia: Anura: Hylidae), with notes on the reproductive activity of S. littoralis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Acoustic repertoire and calling behavior of Scinax fuscomarginatus (Anura, Hylidae)

Vocalizations are important in anuran communication, especially during the breeding season. Calling affects spatial organization of males at breeding sites, promotes attraction of new individuals to the chorus, and attracts mature females for reproduction. We describe four distinct vocalizations (advertisement calls, sporadic calls, and two types of aggressive calls) emitted by adult males of Scinax fuscomarginatus. With the exception of the advertisement call, the remaining descriptions are novel. We also describe calling sites, calling season, and nightly calling activity. Fieldwork was made in a fragment of Cerrado (Estação Ecológica de Itirapina), Municipalities of Itirapina and Brotas, State of São Paulo, southeastern Brazil. At this ecological station, S. fuscomarginatus exhibits a complex acoustic repertoire, social interactions and a prolonged reproductive pattern similar to observations of congeneric species at other localities. Copyright 2005 Society for the Study of Amphibians and Reptiles.

Calling sites and acoustic partitioning in species of the Hyla nana and rubicundula groups (Anura, Hylidae)

We analysed spatial and acoustic partitioning among four species of Hyla belonging to two species-groups: nana (H. nana and H. sanborni) and rubicundula (H. elianeae and H. jimi). Field activities were conducted at three permanent ponds, from 1998 through 2001. Four attributes of the calling sites were analysed: perch height, distance of the perch from the edge of the pond, type of perch (vegetation) and the individual's position on the perch. There was extensive overlap in the four calling-site variables analysed. However, we found spatial segregation did occur in calling site height and the distance of perches from pond edges. Bioacoustic analyses revealed behavioural differences among species in calling activity, both time of onset and peak calling in chorus. There was acoustic partitioning among species the fundamental frequency of the advertisement calls, principally as a function of the temporal structure (e.g. note duration, rate of note repetition, duration and rate of repetition of the calling pulses). We propose that differences in physical attributes of calling site and in characteristics of calls allow these species to exist in sympatry.

The anuran calling repertoire in the light of social context

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Temporal and spatial distribution of anurans in the Pampa Region (Santa Maria, RS).

The present study aimed to determine the richness, occurrence constancy, reproductive modes. standard of abundance distribution, season of vocalization and to test correlation among climatic variables and activity of vocalization of anurans in a region of the Pampa Biome, Santa Maria, Rio Grande do Sul State. During the period of Novernber/2001 to October/2002 monthly collections were carried out utilizing the `survey at breeding site` method and examination of specimens kept in the Colecao Herpetologica do Setor de Zoologia da Universidade Federal de Santa Maria (ZUFSM). Tire Occurrence of 25 species of anurans was recorded. The anurofauna recorded represents 30% of the species known to Occur in Rio Grande do Sul, and comprises species generally associated with grasslands in this state and neighboring countries. Four reproductive modes were recorded: mode 1 (14 species: 58.3%) mode 11 and 30 (9 species` 37.5%) and mode 24 (1 species; 4.2%). The low diversification of reproductive modes is likely related to the homogeneity of the grassland habitat. Most species were constant or accessory in the Study area and the species abundance distribution patterns fit in the Broken Stick and Log-normal models. characterized by homogeneity of species abundance distribution. Most species showed great plasticity in habitat. but few were plastic in vocalization sites use. There was a weak positive correlation between species richness and precipitation. There was also a weak positive correlation between the abundance of species calling activity and maximum average temperatures. These correlations indicated that, in the study area. the abundance of calling males is more affected by the temperature, and species richness is more affected by precipitation, despite the fact that significantly higher species richness occurs during the hottest period of the year. These results showed that the climatological variables examined were not enough to explain the seasonal occurrence of species, thus the influence of other environmental variables merit to be tested in future studies.

Ecology and reproductive biology of two species of Aplastodiscus (Anura : Hylidae) in the Atlantic forest, Brazil

The present study was conducted in the Serra do Japi in the State of São Paulo, Brazil. From March 2004 to January 2006 we studied the ecology and reproductive biology of two sympatric species of Aplastodiscus in three different habitats: lake, stream, and swamp. The majority of A. leucopygius males in calling activity were recorded during the rainy season and during sporadic rains in the dry season (April to September). The same was observed for A. arildae. Most courtship displays of A. leucopygius were observed mainly during the rainy period and only one courtship behaviour was observed for A. arildae during a rainy night, in December 2005. Aplastodiscus leucopygius males were found in activity in the three habitats surveyed. In contrast, males of A. arildae were found in only one habitat (stream). Spatial distribution seems to be the main mechanism of reproductive segregation between the studied species.

Distribuição temporal e espacial de anuros em área de Pampa, Santa Maria, RS

Este estudo teve como objetivo determinar a riqueza, a constância de ocorrência, os modos reprodutivos, o padrão de distribuição da abundância, a temporada de vocalização e testar a correlação das variáveis climáticas sobre a atividade de vocalização dos anuros em uma região do Bioma Pampa, Santa Maria, Rio Grande do Sul. Durante o período de novembro de 2001 a outubro de 2002 foram realizadas coletas mensais empregando o método de busca em sítio de reprodução e exame de exemplares depositados na Coleção Herpetológica do Setor de Zoologia da Universidade Federal de Santa Maria (UFSM) (ZUFSM). Foi registrada a ocorrência de 25 espécies de anuros. A anurofauna registrada corresponde a 30% das espécies encontradas no Rio Grande do Sul e normalmente está associada a áreas abertas encontradas no estado e em países vizinhos. Foram registrados quatro modos reprodutivos: modo 1 (14 espécies; 58,3%); modos 11 e 30 (nove espécies; 37,5%) e modo 24 (uma espécie; 4,2%). A baixa diversificação de modos reprodutivos provavelmente está relacionada à homogeneidade do hábitat primariamente campestre. A maior parte das espécies mostrou-se constante ou acessória na área estudada e o padrão de distribuição da abundância das espécies apresentou ajuste aos modelos Broken Stick e Log-normal, caracterizados pela homogeneidade na distribuição da abundância das espécies. A maioria das espécies apresentou grande plasticidade na ocupação de hábitats, mas poucas foram plásticas no uso dos sítios de vocalização. Houve correlação positiva, ainda que fraca, da riqueza de espécies com a precipitação mensal acumulada e da abundância com a temperatura média máxima. As correlações obtidas indicaram que na área estudada a temperatura parece atuar mais sobre a abundância de machos em atividade de vocalização e a precipitação sobre a riqueza, apesar da riqueza de espécies ser significativamente maior durante o período mais quente do ano. Estes resultados revelaram que as variáveis climatológicas testadas explicaram muito pouco da ocorrência sazonal das espécies, assim a influência de outras variáveis ambientais merece ser testada em estudos futuros.

História natural de Hypsiboas prasinus (Anura: Hylidae) na Serra do Japi, município de Jundiaí, São Paulo, Brasil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Atividade sazonal e uso do ambiente por anfíbios da Mata Atlântica no alto da Serra do Mar

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Diversidade de anuros (Amphibia) do Parque Estadual Morro do Diabo, SP

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)