See you later: roost fidelity of the "Boomerang Bats",Artibeus lituratus (Olfers, 1818) (Mammalia, Chiroptera) / Até mais tarde: fidelidade de abrigo dos "Morcegos Boomerang", Artibeus lituratus (Olfers, 1818) (Mammalia, Chiroptera)

Animals exhibit sociability behaviors and spatial use patterns that are important for species survival. Bats are animals that exhibit complex patterns of aggregation of individuals, which can vary according to sex and age. Aggregation can be explained by active or passive mechanisms. In this behavioural note, we report a group of female Artibeus lituratus in the reproductive stage that exhibits aggregation behavior supporting the active mechanism hypothesis. The females returned to the same roost, for two reproductive season, maintaining the aggregation with the same individuals with which the social bonds were already established.

Os animais exibem comportamentos de sociabilidade e padrões de uso espacial que são importantes para a sobrevivência das espécies. Os morcegos são animais que apresentam padrões complexos de agregação de indivíduos, que podem variar de acordo com o sexo e a idade. A agregação pode ser explicada por mecanismos ativos ou passivos. Nesta nota comportamental, relatamos um grupo de fêmeas de Artibeus lituratus em fase reprodutiva que exibe comportamento de agregação apoiando a hipótese do mecanismo ativo. As fêmeas retornaram ao mesmo poleiro, por duas estações reprodutivas, mantendo a agregação com os mesmos indivíduos com os quais os laços sociais já foram estabelecidos.

Type of shelter and first description of the echolocation call of disk-winged bat (Thyroptera devivoi) / Tipo de abrigo e primeira descrição da chamada de ecolocalização de morcegos com asas de disco (Thyroptera devivoi)

Abstract: Thyropteridae is a family of bats endemic to the Neotropical region, and Thyroptera devivoi is the only species in the family that occurs exclusively in forest patches within savannas of northern South America and north of the Brazilian Cerrado. Primary data on the species are still scarce. Therefore, in this study our objective was to fill knowledge gaps on geographical distribution, roost-use, and echolocation for the species. We observed a T. devivoi colony of 15 individuals living under a dead palm leaf. The bats used the leaf as a roost for at least four days. After capturing one individual, we confirmed the species identification via skull size and the oblong shape of the adhesive disk. The new record reinforces the association of this species with non-forested formations, and its occurrence mainly in savannas. Echolocation calls of T. devivoi are consistent with those known for the genus, with multiharmonic, low intensity and high frequency pulses. Despite these new data, more studies are certainly needed to enhance distribution data for the species, as well as to clarify the biological and ecological requirements of the species.

Resumo: Thyropteridae é uma família de morcegos endêmica da região Neotropical e Thyroptera devivoi é a única espécie da família que ocorre exclusivamente em manchas florestais das savanas do norte de América do Sul e do Cerrado Brasileiro. Dados primários da espécie são ainda escassos e o objetivo deste estudo foi preencher lacunas de conhecimento sobre distribuição geográfica, uso de abrigos e padrões de ecolocalização da espécie. Nós observamos uma colônia de T. devivoi com 15 indivíduos vivendo sob uma folha morta de palmeira. Os morcegos usaram a folha como abrigo ao menos por quatro dias. Depois de capturar um indivíduo, nós confirmamos a identificação da espécie por meio da morfologia do crânio e do disco adesivo. O novo registro reforça a associação da espécie com formações não florestais e a ocorrência principalmente em savanas. Os chamados de ecolocalização de T. devivoi são consistentes com o conhecido para o gênero, com pulsos multi-harmônicos de baixa intensidade e alta frequência. A despeito destes novos dados, mais estudos são certamente necessários para aprimorar os dados de distribuição assim como os requerimentos biológicos da espécie.

Bat flies aggregation on Artibeus planirostris hosts in the Pantanal floodplain and surrounding plateaus.

For parasites in natural systems, the most common pattern of spatial distribution is aggregation among hosts. The main causes of such aggregation are variable exposure of hosts to parasites and heterogeneity in host susceptibility. The objective of this study was to determine if there are differences in the aggregation pattern of two species of ectoparasitic flies between the Pantanal and Cerrado regions of Brazil on the bat Artibeus planirostris. We collected the ectoparasites from bats captured between 2002 and 2017 with mist nets in 21 sites in the Pantanal and 15 sites in the surrounding plateaus. The results showed that the aggregation of ectoparasitic flies in Pantanal was more pronounced than in Cerrado. The discrepancy aggregation index (D) of the bat fly Megistopoda aranea was 0.877 in Pantanal and 0.724 in Cerrado. The D values of Aspidoptera phyllostomatis was even higher, with 0.916 and 0.848 in the Pantanal and Cerrado, respectively. Differences in the shelters used may be the main factor shaping variation in aggregation, since the Pantanal does not have rock formations, with only foliage, crowns and hollow tree trunks. These differences likely affect host exposure to the parasites, leading to an increase in parasite aggregation.

Noise as an informational cue for decision-making: the sound of rain delays bat emergence.

Background noise can have strong negative consequences for animals, reducing individual fitness by masking communication signals, impeding prey detection and increasing predation risk. While the negative impacts of noise across taxa have been well documented, the use of noise as an informational cue, providing animals with reliable information on environmental conditions, has been less well studied. In the tropical rainforest, downpours can be intense and frequent. Strong rainfall may impede efficient orientation and foraging for bats that need echolocation to both navigate and detect prey, and can result in higher flight costs due to increased metabolic rates. Using playback experiments at natural roosts, we tested whether two bat species, differing in their hunting strategies and foraging habitats, use rain noise as a cue to delay emergence from their roosts. We found that both species significantly delayed their emergence time during rain noise playbacks versus silence and ambient noise controls. We conclude that bats can use background noise, here the acoustic component of rainfall, as a reliable informational cue to make informed decisions, in this case about whether to initiate foraging trips or remain in the shelter of their roosts. Our findings suggest that environmental background noise can sometimes be beneficial to animals, in particular in situations where other sensory cues may be absent.

Resolving the paradox of clumped seed dispersal: positive density and distance dependence in a bat-dispersed species.

One of the hypothesized benefits of seed dispersal is to escape density- and distance-responsive, host-specific, natural enemies near maternal plants where conspecific seed and seedling densities are high. Such high conspecific neighbor densities typically result in lower offspring growth and survival (i.e., negative density-dependent effects), yet many dispersal modes result in clumped seed distributions. New World leaf-nosed bats transport fruits to their feeding roosts and deposit seeds, thereby creating high-density seed/seedling patches beneath feeding roosts in heterospecific trees away from maternal trees, which seemingly nullifies a key benefit of seed dispersal. Such dispersal may still be adaptive if negative density-dependent effects are reduced under feeding roosts or if the benefit of being dispersed away from maternal trees outweighs negative effects of conspecific seed/seedling density below roosts. We mapped the entire post-germination population of a bat-dispersed tree species Calophyllum longifolium (Calophyllaceae) in a 50-ha plot on Barro Colorado Island, Panama in each of three successive years. We tested two hypotheses: (1) distance-dependent effects are stronger than density-dependent effects on seedling performance because seedlings far from conspecific adults are more likely to escape natural enemies even when at high densities and (2) negative density-dependent effects will be reduced far from vs. near conspecific adults. Density and distance were naturally decoupled, as expected. However, in contrast to our expectation, we found positive density effects on seedling survival and density-dependent effects did not differ with distance from conspecific adults. Both density and distance had positive effects on seedling survival when considered together, while only year had a significant effect on seedling growth. Thus, both being dispersed under bat feeding roosts and escaping the vicinity of conspecific adults were beneficial for C. longifolium seedling survival, supporting the directed dispersal and escape hypotheses, respectively. Despite resulting in high densities of conspecific seedlings, favorable habitat under bat feeding roosts and lack of negative density-dependent effects appear to provide evolutionary advantages in C. longifolium.

Differences between caves with and without bats in a Brazilian karst habitat

Since bats shelter in roosts during their period of diurnal inactivity, the quality and availability of roosts are important aspects of their ecology. Karst areas have great potential for the availability of day roosts, since they form caves, which serve as bat shelters. Here we characterize the caves used by bats in a preserved karst area of Southeastern Brazil. Using logistic regression analysis we identified the cave characteristics that influence bat occupation. Sixty-six caves were characterized based on measurements of internal height and width, height and width of the entrance(s) of the cave, number of entrances, maximum horizontal development of cave, and internal temperature and humidity. In nineteen months we found 14 species in 32 caves. Most species were eventually recorded in multiple caves, with the exception of D. rotundus, G. soricina and A. planirostris, which were always found in the same caves. Desmodus rotundus showed maternity roost fidelity. We found no differences in microclimate between the caves that are occupied and those that are not. In other words, the microclimate of the caves studied herein can be characterized as stable over the years. The only predictor affecting the presence of bats in the study area was the cave’s maximum horizontal development: the caves that are occupied have greater horizontal development. Based on our results, we conclude that bats occupy many of the caves and that some species are more frequent in certain caves than in others, including some roosts that are used as maternity roosts. These findings indicate that these caves are important resources for the bats in the karst environment studied, and should be preserved.

Differences between caves with and without bats in a Brazilian karst habitat

Since bats shelter in roosts during their period of diurnal inactivity, the quality and availability of roosts are important aspects of their ecology. Karst areas have great potential for the availability of day roosts, since they form caves, which serve as bat shelters. Here we characterize the caves used by bats in a preserved karst area of Southeastern Brazil. Using logistic regression analysis we identified the cave characteristics that influence bat occupation. Sixty-six caves were characterized based on measurements of internal height and width, height and width of the entrance(s) of the cave, number of entrances, maximum horizontal development of cave, and internal temperature and humidity. In nineteen months we found 14 species in 32 caves. Most species were eventually recorded in multiple caves, with the exception of D. rotundus, G. soricina and A. planirostris, which were always found in the same caves. Desmodus rotundus showed maternity roost fidelity. We found no differences in microclimate between the caves that are occupied and those that are not. In other words, the microclimate of the caves studied herein can be characterized as stable over the years. The only predictor affecting the presence of bats in the study area was the caves maximum horizontal development: the caves that are occupied have greater horizontal development. Based on our results, we conclude that bats occupy many of the caves and that some species are more frequent in certain caves than in others, including some roosts that are used as maternity roosts. These findings indicate that these caves are important resources for the bats in the karst environment studied, and should be preserved.(AU)

Seed rain generated by bats under Cerrados pasture remnant trees in a Neotropical savanna

Abstract In this study we described the seed rain generated by bats under four Cerrados tree species common within pastures, Buchenavia tomentosa, Couepia grandiflora, Licania humilis and Qualea grandiflora. We analyzed the similarity among the four tree species in terms of seed rain composition, and compared the number of seeds and seed species deposited under them. Besides that, we assessed the relationship between seed rain intensity and the density of each tree species. Then, we randomly selected 10 mature trees of each species to sample seed rain. We recorded a total of 4892 bat dispersed seeds from 11 species. Also, we observed that along the year seed deposition varied substantially under all trees. At least two seed sub-communities could be distinguished according to tree species used by bats as feeding roost. One related to Couepia grandiflora and Licania humilis, and the other to Buchenavia tomentosa and Qualea grandiflora trees. The variability of seed rain composition in any particular tree and the range of actual seed fall into a particular species indicate patchiness in seed rain, and the overall results appear to be consistent in terms of a substantial and diverse seed rain generated by bats in a highly anthropized landscape. This is the first study concerning seed dispersal by bats in modified Brazilian Cerrado, one of the most endangered biomes in the world. In this respect, by preserving a dense and diverse collection of remnant trees within today's pastures may, potentially, contribute to a faster Cerrado recovery in extensive areas that can be reclaimed for restoration in the future.

Resumo Neste estudo descrevemos a chuva de sementes gerada por morcegos sob quatro espécies arbóreas comuns em pastagens no Cerrado (Bouchenavia tomentosa, Couepia grandiflora, Licania humilis e Qualea grandiflora). Também, analisamos a similaridade quanto à composição da chuva de sementes depositada sob as quatro espécies arbóreas, além da relação entre a intensidade da chuva de sementes e densidade de cada espécies arbóreas. Para tanto, selecionamos aleatoriamente 10 árvores por espécie que fossem reprodutivamente maduras, para amostrar a chuva de sementes. Registramos um total de 4892 sementes, pertencentes a 11 espécies de plantas, dispersadas por morcegos. Durante o ano a deposição de sementes variou substancialmente sob todas as árvores amostradas. Duas sub-comunidades de sementes emergiram associadas às espécies arbóreas usadas por morcegos como abrigo de alimentação. Uma relacionada à Couepia grandiflora e Licania humilis, e outra relacionada à Buchenavia tomentosa e Qualea grandiflora. A variabilidade da composição da chuva de sementes sob qualquer uma das árvores, bem como a amplitude dessa chuva sob cada espécie de árvore indicou um padrão heterogêneo e intenso de deposição de uma coleção diversa de sementes em uma área altamente antropizada. Neste aspecto, a manutenção de uma rica e densa coleção de árvores remanescentes nas áreas de pastagens pode contribuir, potencialmente, para uma regeneração mais rápida do Cerrado em extensas áreas que podem requerer planos de restauração futuramente.

Seed rain generated by bats under Cerrado’s pasture remnant trees in a Neotropical savanna / Chuva de sementes gerada por morcegos sob árvores remanescentes do Cerrado no Brasil Central

Abstract In this study we described the seed rain generated by bats under four Cerrado’s tree species common within pastures, Buchenavia tomentosa, Couepia grandiflora, Licania humilis and Qualea grandiflora. We analyzed the similarity among the four tree species in terms of seed rain composition, and compared the number of seeds and seed species deposited under them. Besides that, we assessed the relationship between seed rain intensity and the density of each tree species. Then, we randomly selected 10 mature trees of each species to sample seed rain. We recorded a total of 4892 bat dispersed seeds from 11 species. Also, we observed that along the year seed deposition varied substantially under all trees. At least two seed sub-communities could be distinguished according to tree species used by bats as feeding roost. One related to Couepia grandiflora and Licania humilis, and the other to Buchenavia tomentosa and Qualea grandiflora trees. The variability of seed rain composition in any particular tree and the range of actual seed fall into a particular species indicate patchiness in seed rain, and the overall results appear to be consistent in terms of a substantial and diverse seed rain generated by bats in a highly anthropized landscape. This is the first study concerning seed dispersal by bats in modified Brazilian Cerrado, one of the most endangered biomes in the world. In this respect, by preserving a dense and diverse collection of remnant trees within today's pastures may, potentially, contribute to a faster Cerrado recovery in extensive areas that can be reclaimed for restoration in the future.

Resumo Neste estudo descrevemos a chuva de sementes gerada por morcegos sob quatro espécies arbóreas comuns em pastagens no Cerrado (Bouchenavia tomentosa, Couepia grandiflora, Licania humilis e Qualea grandiflora). Também, analisamos a similaridade quanto à composição da chuva de sementes depositada sob as quatro espécies arbóreas, além da relação entre a intensidade da chuva de sementes e densidade de cada espécies arbóreas. Para tanto, selecionamos aleatoriamente 10 árvores por espécie que fossem reprodutivamente maduras, para amostrar a chuva de sementes. Registramos um total de 4892 sementes, pertencentes a 11 espécies de plantas, dispersadas por morcegos. Durante o ano a deposição de sementes variou substancialmente sob todas as árvores amostradas. Duas sub-comunidades de sementes emergiram associadas às espécies arbóreas usadas por morcegos como abrigo de alimentação. Uma relacionada à Couepia grandiflora e Licania humilis, e outra relacionada à Buchenavia tomentosa e Qualea grandiflora. A variabilidade da composição da chuva de sementes sob qualquer uma das árvores, bem como a amplitude dessa chuva sob cada espécie de árvore indicou um padrão heterogêneo e intenso de deposição de uma coleção diversa de sementes em uma área altamente antropizada. Neste aspecto, a manutenção de uma rica e densa coleção de árvores remanescentes nas áreas de pastagens pode contribuir, potencialmente, para uma regeneração mais rápida do Cerrado em extensas áreas que podem requerer planos de restauração futuramente.

Seed rain generated by bats under Cerrados pasture remnant trees in a Neotropical savanna / Chuva de sementes gerada por morcegos sob árvores remanescentes do Cerrado no Brasil Central

In this study we described the seed rain generated by bats under four Cerrados tree species common within pastures, Buchenavia tomentosa, Couepia grandiflora, Licania humilis and Qualea grandiflora. We analyzed the similarity among the four tree species in terms of seed rain composition, and compared the number of seeds and seed species deposited under them. Besides that, we assessed the relationship between seed rain intensity and the density of each tree species. Then, we randomly selected 10 mature trees of each species to sample seed rain. We recorded a total of 4892 bat dispersed seeds from 11 species. Also, we observed that along the year seed deposition varied substantially under all trees. At least two seed sub-communities could be distinguished according to tree species used by bats as feeding roost. One related to Couepia grandiflora and Licania humilis, and the other to Buchenavia tomentosa and Qualea grandiflora trees. The variability of seed rain composition in any particular tree and the range of actual seed fall into a particular species indicate patchiness in seed rain, and the overall results appear to be consistent in terms of a substantial and diverse seed rain generated by bats in a highly anthropized landscape. This is the first study concerning seed dispersal by bats in modified Brazilian Cerrado, one of the most endangered biomes in the world. In this respect, by preserving a dense and diverse collection of remnant trees within today's pastures may, potentially, contribute to a faster Cerrado recovery in extensive areas that can be reclaimed for restoration in the future.(AU)

Neste estudo descrevemos a chuva de sementes gerada por morcegos sob quatro espécies arbóreas comuns em pastagens no Cerrado (Bouchenavia tomentosa, Couepia grandiflora, Licania humilis e Qualea grandiflora). Também, analisamos a similaridade quanto à composição da chuva de sementes depositada sob as quatro espécies arbóreas, além da relação entre a intensidade da chuva de sementes e densidade de cada espécies arbóreas. Para tanto, selecionamos aleatoriamente 10 árvores por espécie que fossem reprodutivamente maduras, para amostrar a chuva de sementes. Registramos um total de 4892 sementes, pertencentes a 11 espécies de plantas, dispersadas por morcegos. Durante o ano a deposição de sementes variou substancialmente sob todas as árvores amostradas. Duas sub-comunidades de sementes emergiram associadas às espécies arbóreas usadas por morcegos como abrigo de alimentação. Uma relacionada à Couepia grandiflora e Licania humilis, e outra relacionada à Buchenavia tomentosa e Qualea grandiflora. A variabilidade da composição da chuva de sementes sob qualquer uma das árvores, bem como a amplitude dessa chuva sob cada espécie de árvore indicou um padrão heterogêneo e intenso de deposição de uma coleção diversa de sementes em uma área altamente antropizada. Neste aspecto, a manutenção de uma rica e densa coleção de árvores remanescentes nas áreas de pastagens pode contribuir, potencialmente, para uma regeneração mais rápida do Cerrado em extensas áreas que podem requerer planos de restauração futuramente.(AU)

Trichobius longipes (Diptera, Streblidae) as a parasite of Phyllostomus hastatus (Chiroptera, Phyllostomidae) / Trichobius longipes (Diptera, Streblidae) como parasita de Phyllostomus hastatus (Chiroptera, Phyllostomidae)

Among the factors that influence the diversity of ectoparasites on bat hosts are the kind of roost and the host's social behavior. Other factors such as sex, reproductive condition and host size may influence the distribution and abundance of ectoparasites. The aim of the present study was to analyze the variation in Streblidae ectoparasites on the bat Phyllostomus hastatus, according to sex and roost type. We caught bats in four houses on Marambaia Island, municipality of Mangaratiba, and in one house at the Federal Rural University of Rio de Janeiro, municipality of Seropédica. We caught 65 females and 50 males of P. hastatus and 664 streblids of four species: Aspidoptera phyllostomatis, Strebla consocia, Trichobius “dugesii” complex and Trichobius longipes. The species T. longipes accounted for more than 99% of all the ectoparasites caught. Female bats were more parasitized than males, in terms of both prevalence and average intensity. The total number of parasites did not vary between resident and non-resident bats. The relationship between the number of individuals of T. longipes and sex and roost type was significant for resident bats. The total number of parasites on males did not differ between bachelor roosts and mixed-sex roosts. The differences found between roosts reflected the differences between the sexes.

Os fatores que influenciam a diversidade de artrópodes ectoparasitos no morcego hospedeiro incluem o tipo de abrigo e o comportamento social da espécie hospedeira. Aspectos como sexo, condição reprodutiva e tamanho do hospedeiro podem influenciar a distribuição e a abundância dos ectoparasitos. Este trabalho teve como objetivo analisar a variação no parasitismo de estreblídeos em Phyllostomus hastatus, considerando os sexos e diferentes abrigos. Os morcegos foram capturados em quatro casas na Ilha da Marambaia, município de Mangaratiba, e em uma casa na Universidade Federal Rural do Rio de Janeiro, município de Seropédica. Foram capturados 65 fêmeas e 50 machos de P. hastatus e 664 dípteros estreblídeos distribuídos em quatro espécies: Aspidoptera phyllostomatis, Strebla consocia, Trichobius complexo “dugesii” e Trichobius longipes. A espécie T. longipes representou mais de 99% das capturas de Streblidae. Fêmeas de morcegos foram mais parasitadas que os machos, tanto em prevalência quanto em intensidade média. O total de parasitos não variou entre os morcegos residentes e os não residentes. O modelo considerado entre o total de T. longipes, o sexo e o abrigo para indivíduos residentes mostrou-se significativo. O total de parasitos em machos não difere entre aqueles oriundos de abrigos de machos solteiros e de abrigos heterossexuais. As diferenças entre os abrigos refletem a diferença no parasitismo entre os sexos dos hospedeiros.

Trichobius longipes (Diptera, Streblidae) as a parasite of Phyllostomus hastatus (Chiroptera, Phyllostomidae) / Trichobius longipes (Diptera, Streblidae) como parasita de Phyllostomus hastatus (Chiroptera, Phyllostomidae)

Among the factors that influence the diversity of ectoparasites on bat hosts are the kind of roost and the host's social behavior. Other factors such as sex, reproductive condition and host size may influence the distribution and abundance of ectoparasites. The aim of the present study was to analyze the variation in Streblidae ectoparasites on the bat Phyllostomus hastatus, according to sex and roost type. We caught bats in four houses on Marambaia Island, municipality of Mangaratiba, and in one house at the Federal Rural University of Rio de Janeiro, municipality of Seropédica. We caught 65 females and 50 males of P. hastatus and 664 streblids of four species: Aspidoptera phyllostomatis, Strebla consocia, Trichobius “dugesii” complex and Trichobius longipes. The species T. longipes accounted for more than 99% of all the ectoparasites caught. Female bats were more parasitized than males, in terms of both prevalence and average intensity. The total number of parasites did not vary between resident and non-resident bats. The relationship between the number of individuals of T. longipes and sex and roost type was significant for resident bats. The total number of parasites on males did not differ between bachelor roosts and mixed-sex roosts. The differences found between roosts reflected the differences between the sexes.

Os fatores que influenciam a diversidade de artrópodes ectoparasitos no morcego hospedeiro incluem o tipo de abrigo e o comportamento social da espécie hospedeira. Aspectos como sexo, condição reprodutiva e tamanho do hospedeiro podem influenciar a distribuição e a abundância dos ectoparasitos. Este trabalho teve como objetivo analisar a variação no parasitismo de estreblídeos em Phyllostomus hastatus, considerando os sexos e diferentes abrigos. Os morcegos foram capturados em quatro casas na Ilha da Marambaia, município de Mangaratiba, e em uma casa na Universidade Federal Rural do Rio de Janeiro, município de Seropédica. Foram capturados 65 fêmeas e 50 machos de P. hastatus e 664 dípteros estreblídeos distribuídos em quatro espécies: Aspidoptera phyllostomatis, Strebla consocia, Trichobius complexo “dugesii” e Trichobius longipes. A espécie T. longipes representou mais de 99% das capturas de Streblidae. Fêmeas de morcegos foram mais parasitadas que os machos, tanto em prevalência quanto em intensidade média. O total de parasitos não variou entre os morcegos residentes e os não residentes. O modelo considerado entre o total de T. longipes, o sexo e o abrigo para indivíduos residentes mostrou-se significativo. O total de parasitos em machos não difere entre aqueles oriundos de abrigos de machos solteiros e de abrigos heterossexuais. As diferenças entre os abrigos refletem a diferença no parasitismo entre os sexos dos hospedeiros.

Sound amplification by means of a horn-like roosting structure in Spix's disc-winged bat.

While sound is a signal modality widely used by many animals, it is very susceptible to attenuation, hampering effective long-distance communication. A strategy to minimize sound attenuation that has been historically used by humans is to use acoustic horns; to date, no other animal is known to use a similar structure to increase sound intensity. Here, we describe how the use of a roosting structure that resembles an acoustic horn (the tapered tubes that form when new leaves of plants such as Heliconia or Calathea species start to unfurl) increases sound amplification of the incoming and outgoing social calls used by Spix's disc-winged bat (Thyroptera tricolor) to locate roosts and group members. Our results indicate that incoming calls are significantly amplified as a result of sound waves being increasingly compressed as they move into the narrow end of the leaf. Outgoing calls were faintly amplified, probably as a result of increased sound directionality. Both types of call, however, experienced significant sound distortion, which might explain the patterns of signal recognition previously observed in behavioural experiments. Our study provides the first evidence of the potential role that a roost can play in facilitating acoustic communication in bats.

Bat assemblages in conservation areas of a metropolitan region in Southeastern Brazil, including an important karst habitat / Assembleias de morcegos em areas de conservacao de uma regiao metropolitana no sudeste do Brasil, incluindo um importante habitat carstico

Species richness and abundance of bats were studied in four nature reserves, including a karst area which has many potential rocky shelters for bats, such as caves and rock crevices. The reserves were located in the greater Belo Horizonte metropolitan area, one of the most populated regions of Brazil, within the Atlantic Forest, and Cerrado (Brazilian savanna) ecological domains. Bats were sampled using mist-nets and, in the karst area, also by active searches in shelters. A total of 1,599 bats were captured representing 30 species belonging to four families. There was little similarity among the four chiropteran faunas. The greatest species richness was found in the karst area with 22 species recorded whereas richness estimates in the other areas indicated the need for further studies. Two hundred and sixty-five individuals of 14 species were captured from 56 shelters. Most of the shelters were frequently used for diurnal roosts, and all the bats found belonged to the Phyllostomidae, with the exception of Myotis nigricans (Vespertilionidae), Nyctinomops laticaudatus (Molossidae) and Peropteryx macrotis (Emballonuridae). The sanguinivorous Desmodus rotundus was the most common species in the shelters. The results of this study demonstrate the importance of maintaining multiple protected areas to ensure a representative fauna of bats in a region characterized by a vegetation transition zone and with intense economic activity and high environmental impact. This study also demonstrates the importance of rock shelters for maintaining local bat richness and the importance of active searches for bats in their diurnal roosts for a more thorough sampling of the bat fauna at a given locality.

Neste estudo, a riqueza e a abundância de espécies de morcegos foram estudadas em quatro reservas naturais, incluindo uma área cárstica com muitas cavernas e fendas em rochas, que constituem abrigos rochosos potenciais para os morcegos. As reservas encontram-se dentro da região metropolitana de Belo Horizonte-MG, uma das mais povoadas do Brasil, e dentro dos domínios de Floresta Atlântica e do Cerrado. Os morcegos foram amostrados com redes de neblina (mist-nets) e, na área cárstica, também foi realizada busca ativa por morcegos em seus abrigos. Foram capturados 1.599 morcegos de 30 espécies, pertencentes a quatro famílias. Houve pouca similaridade entre as faunas de quirópteros analisadas. A maior riqueza foi encontrada na área cárstica, com 22 espécies registradas com redes de neblina e em seus abrigos; entretanto, estimativas de riqueza indicaram a necessidade de mais estudos nas outras áreas. Do total amostrado, 265 indivíduos de 14 espécies foram capturados em 56 abrigos. A maioria dos abrigos era ocupada no período diurno e de uso frequente; os morcegos presentes eram filostomídeos, exceto Myotis nigricans (Vespertilionidae), Nyctinomops laticaudatus (Molossidae) e Peropteryx macrotis (Emballonuridae). O hematófago Desmodus rotundus foi o mais frequente nos abrigos. O resultado deste estudo indica a importância da manutenção de diferentes áreas para a conservação dos quirópteros em região caracterizada como zona de transição vegetacional e com intensa atividade econômica e impacto ambiental. Este estudo demonstra também a importância dos abrigos rochosos para a riqueza local de espécies e a importância de busca ativa por morcegos em seus abrigos diurnos para uma amostragem mais efetiva da fauna local destes quirópteros.

Bat assemblages in conservation areas of a metropolitan region in southeastern Brazil, including an important karst habitat / Assembleias de morcegos em áreas de conservação de uma região metropolitana no sudeste do Brasil, incluindo um importante hábitat cárstico

Species richness and abundance of bats were studied in four nature reserves, including a karst area which has many potential rocky shelters for bats, such as caves and rock crevices. The reserves were located in the greater Belo Horizonte metropolitan area, one of the most populated regions of Brazil, within the Atlantic Forest, and Cerrado (Brazilian savanna) ecological domains. Bats were sampled using mist-nets and, in the karst area, also by active searches in shelters. A total of 1,599 bats were captured representing 30 species belonging to four families. There was little similarity among the four chiropteran faunas. The greatest species richness was found in the karst area with 22 species recorded whereas richness estimates in the other areas indicated the need for further studies. Two hundred and sixty-five individuals of 14 species were captured from 56 shelters. Most of the shelters were frequently used for diurnal roosts, and all the bats found belonged to the Phyllostomidae, with the exception of Myotis nigricans (Vespertilionidae), Nyctinomops laticaudatus (Molossidae) and Peropteryx macrotis (Emballonuridae). The sanguinivorous Desmodus rotundus was the most common species in the shelters. The results of this study demonstrate the importance of maintaining multiple protected areas to ensure a representative fauna of bats in a region characterized by a vegetation transition zone and with intense economic activity and high environmental impact. This study also demonstrates the importance of rock shelters for maintaining local bat richness and the importance of active searches for bats in their diurnal roosts for a more thorough sampling of the bat fauna at a given locality.(AU)

Neste estudo, a riqueza e a abundância de espécies de morcegos foram estudadas em quatro reservas naturais, incluindo uma área cárstica com muitas cavernas e fendas em rochas, que constituem abrigos rochosos potenciais para os morcegos. As reservas encontram-se dentro da região metropolitana de Belo Horizonte-MG, uma das mais povoadas do Brasil, e dentro dos domínios de Floresta Atlântica e do Cerrado. Os morcegos foram amostrados com redes de neblina (mist-nets) e, na área cárstica, também foi realizada busca ativa por morcegos em seus abrigos. Foram capturados 1.599 morcegos de 30 espécies, pertencentes a quatro famílias. Houve pouca similaridade entre as faunas de quirópteros analisadas. A maior riqueza foi encontrada na área cárstica, com 22 espécies registradas com redes de neblina e em seus abrigos; entretanto, estimativas de riqueza indicaram a necessidade de mais estudos nas outras áreas. Do total amostrado, 265 indivíduos de 14 espécies foram capturados em 56 abrigos. A maioria dos abrigos era ocupada no período diurno e de uso frequente; os morcegos presentes eram filostomídeos, exceto Myotis nigricans (Vespertilionidae), Nyctinomops laticaudatus (Molossidae) e Peropteryx macrotis (Emballonuridae). O hematófago Desmodus rotundus foi o mais frequente nos abrigos. O resultado deste estudo indica a importância da manutenção de diferentes áreas para a conservação dos quirópteros em região caracterizada como zona de transição vegetacional e com intensa atividade econômica e impacto ambiental. Este estudo demonstra também a importância dos abrigos rochosos para a riqueza local de espécies e a importância de busca ativa por morcegos em seus abrigos diurnos para uma amostragem mais efetiva da fauna local destes quirópteros.(AU)

Synanthropic behavior of the Neotropical palm swift Tachornis squamata (Apodiformes: Apodidae) in the Brazilian Caatinga

The Neotropical palm swift, Tachornis squamata Cassin, 1853 (Apodidae), inhabits palm forests in the northern, northeastern and central regions of South America. At the Chapada do Apodi, Brazilian Caatinga, we investigated how the Neotropical palm swifts use palm trees to roost in two areas: urban and exurban. From May to November 2011 and from March to June 2012, out of the breeding season of the species, we compared the differences between the descriptive parameters of the palm-roosts and the activity levels of the swifts in urban and exurban roosting. We sampled 30 carnauba palm-roosts in exurban areas and 32 carnauba palm-roosts and 26 Chinese fan palm-roosts in urban areas for a period of 132 days, a total of 528 hours of sampling. The number of wasp nests was greater in carnauba palm-roosts in exurban areas than in palm-roosts in urban areas. However, there were greater numbers of swift nests and swifts in palm-roosts in urban areas than in exurban areas. Moreover, the activity levels (number of entry and exit events of swifts in the palm-roost) during sunrise (05:00-05:20 a.m.) and sunset (05:41-06:00 p.m.) were significantly lower in the exurban area than in the urban area. These results may contribute to establish better management practices for the coexistence between wildlife and humans in cities.

Synanthropic behavior of the Neotropical palm swift Tachornis squamata (Apodiformes: Apodidae) in the Brazilian Caatinga

The Neotropical palm swift, Tachornis squamata Cassin, 1853 (Apodidae), inhabits palm forests in the northern, northeastern and central regions of South America. At the Chapada do Apodi, Brazilian Caatinga, we investigated how the Neotropical palm swifts use palm trees to roost in two areas: urban and exurban. From May to November 2011 and from March to June 2012, out of the breeding season of the species, we compared the differences between the descriptive parameters of the palm-roosts and the activity levels of the swifts in urban and exurban roosting. We sampled 30 carnauba palm-roosts in exurban areas and 32 carnauba palm-roosts and 26 Chinese fan palm-roosts in urban areas for a period of 132 days, a total of 528 hours of sampling. The number of wasp nests was greater in carnauba palm-roosts in exurban areas than in palm-roosts in urban areas. However, there were greater numbers of swift nests and swifts in palm-roosts in urban areas than in exurban areas. Moreover, the activity levels (number of entry and exit events of swifts in the palm-roost) during sunrise (05:00-05:20 a.m.) and sunset (05:41-06:00 p.m.) were significantly lower in the exurban area than in the urban area. These results may contribute to establish better management practices for the coexistence between wildlife and humans in cities.

Maximum weight capacity of leaves used by tent-roosting bats: implicatons for social structure

Fewer than 2% of bats can modify their environment to construct roosts. Tent-roosting bats cut and fold leaves to form roosts called tents. Unlike the caves or hollow trees used by some bats, leaves possess an upper limit on their capacity to support weight. We tested the hypothesis that the maximum weight capacity that leaves can support limits the maximum social group size of bats that roost in them. We conducted research in the Tirimbina Biological Reserve (TBR), Sarapiquí, Costa Rica, between March and April 2012. We added weight incrementally to new leaves of three plant species until the angle of the leaves fell below that which bats naturally use. Philodendron fragrantissimum and Heliconia imbricata support one-third more weight than Asterogyne martiana. This study demonstrates that the maximum weight that the leaves can support is similar to the mean social group weight of D. watsoni and Ectophylla alba reported in the literature for these plant species and lower than the maximum reported social group weights. Therefore, it is possible that the maximum weight capacity of the leaves used to construct roosts limits the maximum social group size.(AU)

Synanthropic behavior of the Neotropical palm swift Tachornis squamata (Apodiformes: Apodidae) in the Brazilian Caatinga

The Neotropical palm swift, Tachornis squamata Cassin, 1853 (Apodidae), inhabits palm forests in the northern, northeastern and central regions of South America. At the Chapada do Apodi, Brazilian Caatinga, we investigated how the Neotropical palm swifts use palm trees to roost in two areas: urban and exurban. From May to November 2011 and from March to June 2012, out of the breeding season of the species, we compared the differences between the descriptive parameters of the palm-roosts and the activity levels of the swifts in urban and exurban roosting. We sampled 30 carnauba palm-roosts in exurban areas and 32 carnauba palm-roosts and 26 Chinese fan palm-roosts in urban areas for a period of 132 days, a total of 528 hours of sampling. The number of wasp nests was greater in carnauba palm-roosts in exurban areas than in palm-roosts in urban areas. However, there were greater numbers of swift nests and swifts in palm-roosts in urban areas than in exurban areas. Moreover, the activity levels (number of entry and exit events of swifts in the palm-roost) during sunrise (05:00-05:20 a.m.) and sunset (05:41-06:00 p.m.) were significantly lower in the exurban area than in the urban area. These results may contribute to establish better management practices for the coexistence between wildlife and humans in cities.