Evidence of vertical migration in the Ipanema bat Pygoderma bilabiatum (Chiroptera: Phyllostomidae: Stenodermatinae)

Migration is defined as a seasonal and cyclic population movement observed in all animal classes and studied mainly in vertebrates. A considerable part of the knowledge on migration comes from birds, for which migration is an important aspect of their biology. In the case of bats, females usually migrate larger distances than males in some species. The present study analyzes the seasonal occurrence of Pygoderma bilabiatum (Wagner, 1843) at different elevations, in order to test for a pattern that evidences migration, using data from the states of Espírito Santo, Minas Gerais, Rio de Janeiro, São Paulo, Paraná, Santa Catarina, and Rio Grande do Sul, Brazil. A total of 529 specimens of P. bilabiatum were captured. Pygoderma bilabiatum seems to be more frequent at intermediate and high elevations (over 80% of all captures were made above 250 m a.s.l.) and at latitudes above 22°S, where rainfall is high (over 1,500 mm) and temperatures are mild (16-23°C). Sex ratio varied with elevation; it was skewed towards males at lower elevations (N = 9, r² = 0.60, F = 12.311, p = 0.008, Sex ratio = 0.0004*elevation + 0.976), though females predominated at all altitudinal bands and in all states analyzed.

Evidence of vertical migration in the Ipanema bat Pygoderma bilabiatum (Chiroptera: Phyllostomidae: Stenodermatinae)

Migration is defined as a seasonal and cyclic population movement observed in all animal classes and studied mainly in vertebrates. A considerable part of the knowledge on migration comes from birds, for which migration is an important aspect of their biology. In the case of bats, females usually migrate larger distances than males in some species. The present study analyzes the seasonal occurrence of Pygoderma bilabiatum (Wagner, 1843) at different elevations, in order to test for a pattern that evidences migration, using data from the states of Espírito Santo, Minas Gerais, Rio de Janeiro, São Paulo, Paraná, Santa Catarina, and Rio Grande do Sul, Brazil. A total of 529 specimens of P. bilabiatum were captured. Pygoderma bilabiatum seems to be more frequent at intermediate and high elevations (over 80% of all captures were made above 250 m a.s.l.) and at latitudes above 22°S, where rainfall is high (over 1,500 mm) and temperatures are mild (16-23°C). Sex ratio varied with elevation; it was skewed towards males at lower elevations (N = 9, r² = 0.60, F = 12.311, p = 0.008, Sex ratio = 0.0004*elevation + 0.976), though females predominated at all altitudinal bands and in all states analyzed.

Evidence of vertical migration in the Ipanema bat Pygoderma bilabiatum (Chiroptera: Phyllostomidae: Stenodermatinae)

Migration is defined as a seasonal and cyclic population movement observed in all animal classes and studied mainly in vertebrates. A considerable part of the knowledge on migration comes from birds, for which migration is an important aspect of their biology. In the case of bats, females usually migrate larger distances than males in some species. The present study analyzes the seasonal occurrence of Pygoderma bilabiatum (Wagner, 1843) at different elevations, in order to test for a pattern that evidences migration, using data from the states of Espírito Santo, Minas Gerais, Rio de Janeiro, São Paulo, Paraná, Santa Catarina, and Rio Grande do Sul, Brazil. A total of 529 specimens of P. bilabiatum were captured. Pygoderma bilabiatum seems to be more frequent at intermediate and high elevations (over 80% of all captures were made above 250 m a.s.l.) and at latitudes above 22°S, where rainfall is high (over 1,500 mm) and temperatures are mild (16-23°C). Sex ratio varied with elevation; it was skewed towards males at lower elevations (N = 9, r² = 0.60, F = 12.311, p = 0.008, Sex ratio = 0.0004*elevation + 0.976), though females predominated at all altitudinal bands and in all states analyzed.

Análise dos Resumos do V EBEQ

Para o V Encontro Brasileiro para o Estudo de Quirópteros, 59 trabalhos foram avaliados pela Comissão Científica. Apesar deste número não parecer tão expressivo quando analisado isoladamente, ele é superior ao de outros EBEQs. É importante também considerar que esta edição do EBEQ está sendo realizada logo após o Congresso Brasileiro de Zoologia (fevereiro de 2010) e cerca de seis meses depois do Congresso Brasileiro de Ecologia (setembro de 2009). Para um encontro que teve algumas tentativas anteriores de realização frustradas e não apresenta periodicidade regular este número de resumo representa, portanto, um sucesso.[...]

Análise dos Resumos do V EBEQ

Para o V Encontro Brasileiro para o Estudo de Quirópteros, 59 trabalhos foram avaliados pela Comissão Científica. Apesar deste número não parecer tão expressivo quando analisado isoladamente, ele é superior ao de outros EBEQs. É importante também considerar que esta edição do EBEQ está sendo realizada logo após o Congresso Brasileiro de Zoologia (fevereiro de 2010) e cerca de seis meses depois do Congresso Brasileiro de Ecologia (setembro de 2009). Para um encontro que teve algumas tentativas anteriores de realização frustradas e não apresenta periodicidade regular este número de resumo representa, portanto, um sucesso.[...]

Capture sequence and relative abundance of bats during surveys

It is expected that rare species will be gradually added to biodiversity surveys over time and that complete inventories will include rare species. The objective in the present work is to test whether the capture sequence of species during a bat survey is related to species abundance. Species with capture rates lower than 0.01x10-3 captures/hour-net were considered rare. At Ilha da Gipóia, rare species accounted for 22.22% of the total and, at Rio das Pedras Reserve, they represented 30.00%. The existence of a negative relationship between the relative abundance and the first night of capture of each species for the Ilha da Gipóia and the high significance level for the accumulation curve at both localities suggest that the documentation of a large number of rare species depends on a sustained capture effort. The common species were captured at the beginning of the field work and the remaining species were typically added to the collection according to their approximate relative abundance. However, rare or seldomly captured species were added at random.

Capture sequence and relative abundance of bats during surveys

It is expected that rare species will be gradually added to biodiversity surveys over time and that complete inventories will include rare species. The objective in the present work is to test whether the capture sequence of species during a bat survey is related to species abundance. Species with capture rates lower than 0.01x10-3 captures/hour-net were considered rare. At Ilha da Gipóia, rare species accounted for 22.22% of the total and, at Rio das Pedras Reserve, they represented 30.00%. The existence of a negative relationship between the relative abundance and the first night of capture of each species for the Ilha da Gipóia and the high significance level for the accumulation curve at both localities suggest that the documentation of a large number of rare species depends on a sustained capture effort. The common species were captured at the beginning of the field work and the remaining species were typically added to the collection according to their approximate relative abundance. However, rare or seldomly captured species were added at random.

Capture sequence and relative abundance of bats during surveys

It is expected that rare species will be gradually added to biodiversity surveys over time and that complete inventories will include rare species. The objective in the present work is to test whether the capture sequence of species during a bat survey is related to species abundance. Species with capture rates lower than 0.01x10-3 captures/hour-net were considered rare. At Ilha da Gipóia, rare species accounted for 22.22% of the total and, at Rio das Pedras Reserve, they represented 30.00%. The existence of a negative relationship between the relative abundance and the first night of capture of each species for the Ilha da Gipóia and the high significance level for the accumulation curve at both localities suggest that the documentation of a large number of rare species depends on a sustained capture effort. The common species were captured at the beginning of the field work and the remaining species were typically added to the collection according to their approximate relative abundance. However, rare or seldomly captured species were added at random.

Feeding behaviour of the bat Phyllostomus hastatus (Pallas 1767) in jackfruit Artocarpus heterophyllus Lamarck (Moraceae), in Ilha Grande, Rio de Janeiro State, Brazil

Artorcarpus heterophyllus fruit is the largest tree fruit, weighing up to 36 kg and was introduced in Brazil during the XVIII century. During a mammalian diversity research developed at Ilha Grande at least five Phyllostomus hastatus bats were observed eating jackfruit. Jackfruit availability is high almost all year long at Ilha Grande and it is possible that P. hastatus restricts the use of this fruit during low availability periods of other food resources. Although seed carrying was not observed, the disperser role of P.hastatus on A. heterophyllus can not be neglected.

Feeding behaviour of the bat Phyllostomus hastatus (Pallas 1767) in jackfruit Artocarpus heterophyllus Lamarck (Moraceae), in Ilha Grande, Rio de Janeiro State, Brazil

Artorcarpus heterophyllus fruit is the largest tree fruit, weighing up to 36 kg and was introduced in Brazil during the XVIII century. During a mammalian diversity research developed at Ilha Grande at least five Phyllostomus hastatus bats were observed eating jackfruit. Jackfruit availability is high almost all year long at Ilha Grande and it is possible that P. hastatus restricts the use of this fruit during low availability periods of other food resources. Although seed carrying was not observed, the disperser role of P.hastatus on A. heterophyllus can not be neglected.

Dados de reprodução de Platyrrhinus lineatus em estudo de longo prazo no Estado do Rio de Janeiro (Mammalia, Chiroptera, Phyllostomidae)

Based on a large bat sampling we analyzed the reproductive biology of Platyrrhinus lineatus (E. Geoffroy, 1810) in the Atlantic Forest, southeastern Brazil. The bats were captured with mist nets from 1989 and 2005, in 27 of the 41 different localities sampled. The beginning of reproductive season was estimated 30 days before the date of capture of the first pregnant female. For determination of the end of the reproductive time we used the date of the capture of the last lactating female, added by 40 days. The total of 688 adult bats was analyzed, of which 58.3% were females. The largest numbers of captures was observed in the months of February, January and August. Males with descent testicles were observed in all of the months. Inactive females were observed in predominance in March and of May to August. Females with palpable fetuses were observed in all of the months except in April, June and July, with peak in August-October and January-February. Lactating females were netted from November to June, with peak in November and February. Females simultaneously pregnant and lactating were captured in all of the months except in July, with peak in April. The size of the reproductive season varied every year, from eight to 12 months, with an average of 10.6 months.

Baseado em uma grande amostragem de morcegos realizada na Mata Atlântica, Estado do Rio de Janeiro, sudeste do Brasil, nós analisamos a biologia reprodutiva de Platyrrhinus lineatus (E. Geoffroy, 1810). Os morcegos foram capturados com redes de neblina entre 1989 e 2005, em 27 das 41 diferentes localidades amostradas. O começo da época reprodutiva foi estimado 30 dias antes da data da captura da primeira fêmea grávida. Para determinação do término da época reprodutiva empregamos a data da captura da última fêmea lactante mais 40 dias. O total de 688 morcegos adultos foi analisado, sendo 58,3% representados por fêmeas. O maior número de capturas foi observado nos meses de fevereiro, janeiro e agosto. Machos com testículos escrotados foram observados em todos os meses. Fêmeas inativas sexualmente foram observadas com predominância em março e de maio a agosto. Fêmeas com fetos palpáveis foram observadas em todos os meses, exceto em abril, junho e julho com pico em agosto-outubro e janeiro-fevereiro. Fêmeas lactantes foram capturadas de novembro a junho, com pico em novembro e fevereiro. Fêmeas simultaneamente grávidas e lactantes foram capturadas em todos os meses exceto em junho, com pico em abril. O tamanho da época reprodutiva variou a cada ano, compreendendo de 8 a 12 meses, com média de 10,6 meses.

Influência do ciclo lunar na captura de morcegos Phyllostomidae

The influence of moonlight on the activity patterns of bats has been reported to some species. In general, bats react to the increase of nocturnal illumination by reducing the use of open spaces, by limiting foraging activity or by shortening the activity periods. To determine the influence of moon cycle on the efficiency of bat netting, captures of 28 night-samplings were analyzed in southeastern Brazil. The capture rate and species richness were inversely related to the moonlight intensity. Among the most frequently netted species, only two showed significant and negative relation with increasing moonlight. The highest variation in species richness was observed in gleaners and nectarivorous species. The days following new moon were the most productive in terms of capture rate and species richness. The local species richness was not archived when sampling was restricted to any single period of the moon cycle. Bat community studies may benefit from samplings spanning the entire moon cycle.

A influência da luz da lua no padrão de atividade de morcegos já foi documentada em algumas espécies. Geralmente os morcegos reagem ao aumento da iluminação reduzindo o uso de espaços abertos e restringindo a atividade de forrageio ou a duração do período de atividade. Para estabelecer a influência do ciclo lunar na eficiência de captura de morcegos, foi realizada uma análise com 28 noites de capturas no sudeste do Brasil. A taxa de captura e a riqueza de espécies apresentaram relação linear inversa com a porção iluminada pela lua. Das espécies mais freqüentemente capturadas, apenas duas apresentaram relação significativa e negativa com o aumento da iluminação pela lua. Maiores variações na riqueza de espécies foram observadas em morcegos catadores e nectarívoros. Os dias após a lua nova são os mais produtivos em relação a capturas e riqueza. A riqueza local não pode ser totalmente amostrada se a amostragem for restrita a qualquer período do ciclo lunar. Para estudar a comunidade de morcegos é mais apropriado realizar amostragem durante todo o ciclo lunar.

Influência do ciclo lunar na captura de morcegos Phyllostomidae

The influence of moonlight on the activity patterns of bats has been reported to some species. In general, bats react to the increase of nocturnal illumination by reducing the use of open spaces, by limiting foraging activity or by shortening the activity periods. To determine the influence of moon cycle on the efficiency of bat netting, captures of 28 night-samplings were analyzed in southeastern Brazil. The capture rate and species richness were inversely related to the moonlight intensity. Among the most frequently netted species, only two showed significant and negative relation with increasing moonlight. The highest variation in species richness was observed in gleaners and nectarivorous species. The days following new moon were the most productive in terms of capture rate and species richness. The local species richness was not archived when sampling was restricted to any single period of the moon cycle. Bat community studies may benefit from samplings spanning the entire moon cycle.

A influência da luz da lua no padrão de atividade de morcegos já foi documentada em algumas espécies. Geralmente os morcegos reagem ao aumento da iluminação reduzindo o uso de espaços abertos e restringindo a atividade de forrageio ou a duração do período de atividade. Para estabelecer a influência do ciclo lunar na eficiência de captura de morcegos, foi realizada uma análise com 28 noites de capturas no sudeste do Brasil. A taxa de captura e a riqueza de espécies apresentaram relação linear inversa com a porção iluminada pela lua. Das espécies mais freqüentemente capturadas, apenas duas apresentaram relação significativa e negativa com o aumento da iluminação pela lua. Maiores variações na riqueza de espécies foram observadas em morcegos catadores e nectarívoros. Os dias após a lua nova são os mais produtivos em relação a capturas e riqueza. A riqueza local não pode ser totalmente amostrada se a amostragem for restrita a qualquer período do ciclo lunar. Para estudar a comunidade de morcegos é mais apropriado realizar amostragem durante todo o ciclo lunar.

Dados de reprodução de Platyrrhinus lineatus em estudo de longo prazo no Estado do Rio de Janeiro (Mammalia, Chiroptera, Phyllostomidae)

Based on a large bat sampling we analyzed the reproductive biology of Platyrrhinus lineatus (E. Geoffroy, 1810) in the Atlantic Forest, southeastern Brazil. The bats were captured with mist nets from 1989 and 2005, in 27 of the 41 different localities sampled. The beginning of reproductive season was estimated 30 days before the date of capture of the first pregnant female. For determination of the end of the reproductive time we used the date of the capture of the last lactating female, added by 40 days. The total of 688 adult bats was analyzed, of which 58.3% were females. The largest numbers of captures was observed in the months of February, January and August. Males with descent testicles were observed in all of the months. Inactive females were observed in predominance in March and of May to August. Females with palpable fetuses were observed in all of the months except in April, June and July, with peak in August-October and January-February. Lactating females were netted from November to June, with peak in November and February. Females simultaneously pregnant and lactating were captured in all of the months except in July, with peak in April. The size of the reproductive season varied every year, from eight to 12 months, with an average of 10.6 months.

Baseado em uma grande amostragem de morcegos realizada na Mata Atlântica, Estado do Rio de Janeiro, sudeste do Brasil, nós analisamos a biologia reprodutiva de Platyrrhinus lineatus (E. Geoffroy, 1810). Os morcegos foram capturados com redes de neblina entre 1989 e 2005, em 27 das 41 diferentes localidades amostradas. O começo da época reprodutiva foi estimado 30 dias antes da data da captura da primeira fêmea grávida. Para determinação do término da época reprodutiva empregamos a data da captura da última fêmea lactante mais 40 dias. O total de 688 morcegos adultos foi analisado, sendo 58,3% representados por fêmeas. O maior número de capturas foi observado nos meses de fevereiro, janeiro e agosto. Machos com testículos escrotados foram observados em todos os meses. Fêmeas inativas sexualmente foram observadas com predominância em março e de maio a agosto. Fêmeas com fetos palpáveis foram observadas em todos os meses, exceto em abril, junho e julho com pico em agosto-outubro e janeiro-fevereiro. Fêmeas lactantes foram capturadas de novembro a junho, com pico em novembro e fevereiro. Fêmeas simultaneamente grávidas e lactantes foram capturadas em todos os meses exceto em junho, com pico em abril. O tamanho da época reprodutiva variou a cada ano, compreendendo de 8 a 12 meses, com média de 10,6 meses.

Bat predation by Phyllostomus hastatus

Predation is well studied experimentally and empirically, even though it may be difficult to be observedin the field for nocturnal species, such as bats. We studied bat assemblages through mist-netting in four AtlanticForest sites in the states of Espírito Santo, Rio de Janeiro and Minas Gerais, Southeastern Brazil. Here we reportthe observation of four predation events of individuals of the species Glossophaga soricina, Carollia perspicillata and Myotis nigricans by Phyllostomus hastatus. Our observations suggest that P. hastatus may opportunistically prey upon smaller bats.

Movement of Artibeus fimbriatus over the sea / Deslocamento de Artibeus fimbriatus sobre o mar

In Brazil, even though the use of permanent marking methods in bats are rare, frugivorous bats are known to move, great distances both in the Amazonian savannas and in urban areas. In this study, the use of permanent marking enabled to observe that Artibeus fimbriatus flewacross 21.7 km of sea demonstrating a possible genic flow between islands and the continent. It is also suggested that these bats can move among more than 400 islands. Such observation reinforces the need to use definitive marking of captured animals to improve movement and dispersal data.

In Brazil, even though the use of permanent marking methods in bats are rare, frugivorous bats are known to move, great distances both in the Amazonian savannas and in urban areas. In this study, the use of permanent marking enabled to observe that Artibeus fimbriatus flewacross 21.7 km of sea demonstrating a possible genic flow between islands and the continent. It is also suggested that these bats can move among more than 400 islands. Such observation reinforces the need to use definitive marking of captured animals to improve movement and dispersal data.

Bat predation by Phyllostomus hastatus

Predation is well studied experimentally and empirically, even though it may be difficult to be observedin the field for nocturnal species, such as bats. We studied bat assemblages through mist-netting in four AtlanticForest sites in the states of Espírito Santo, Rio de Janeiro and Minas Gerais, Southeastern Brazil. Here we reportthe observation of four predation events of individuals of the species Glossophaga soricina, Carollia perspicillata and Myotis nigricans by Phyllostomus hastatus. Our observations suggest that P. hastatus may opportunistically prey upon smaller bats.

Movement of Artibeus fimbriatus over the sea / Deslocamento de Artibeus fimbriatus sobre o mar

In Brazil, even though the use of permanent marking methods in bats are rare, frugivorous bats are known to move, great distances both in the Amazonian savannas and in urban areas. In this study, the use of permanent marking enabled to observe that Artibeus fimbriatus flewacross 21.7 km of sea demonstrating a possible genic flow between islands and the continent. It is also suggested that these bats can move among more than 400 islands. Such observation reinforces the need to use definitive marking of captured animals to improve movement and dispersal data.

In Brazil, even though the use of permanent marking methods in bats are rare, frugivorous bats are known to move, great distances both in the Amazonian savannas and in urban areas. In this study, the use of permanent marking enabled to observe that Artibeus fimbriatus flewacross 21.7 km of sea demonstrating a possible genic flow between islands and the continent. It is also suggested that these bats can move among more than 400 islands. Such observation reinforces the need to use definitive marking of captured animals to improve movement and dispersal data.

Morcegos cavernícolas da Área de Proteção Ambiental (APA) Nascentes do Rio Vermelho, Goiás

Caves are essential roosts for most species of bats and 25% of the Brazilian species were already sampled at caves. In spite of the extensive carste area observed in Brazil, few lists of cave bats are available in Brazil. We accomplished inventory in the APA Nascentes do Rio Vermelho and we compared the richness with other published samples. Twentyeight species of bats were confirmed in APANRV, of which 75% were captured at caves. The number of species of bats for each cave varied from 2 to 16, with an average of 7.54 species. Of the five caves sampledboth in the rainy season and in the dry season, three showed more species during dry season. It was not obtained significant linear relationship between the geographical distance and the Jaccard similarity among the samples. The simple regression between the observed richness and the number of sampled caves in all available Brazilian samples was significantand positive; however it was not obtained significant relationship of the richness with the latitude and the biome.

Morcegos cavernícolas da Área de Proteção Ambiental (APA) Nascentes do Rio Vermelho, Goiás

Caves are essential roosts for most species of bats and 25% of the Brazilian species were already sampled at caves. In spite of the extensive carste area observed in Brazil, few lists of cave bats are available in Brazil. We accomplished inventory in the APA Nascentes do Rio Vermelho and we compared the richness with other published samples. Twentyeight species of bats were confirmed in APANRV, of which 75% were captured at caves. The number of species of bats for each cave varied from 2 to 16, with an average of 7.54 species. Of the five caves sampledboth in the rainy season and in the dry season, three showed more species during dry season. It was not obtained significant linear relationship between the geographical distance and the Jaccard similarity among the samples. The simple regression between the observed richness and the number of sampled caves in all available Brazilian samples was significantand positive; however it was not obtained significant relationship of the richness with the latitude and the biome.