CECAV

URI permanente desta comunidadehttps://bdc.icmbio.gov.br/handle/cecav/1

Centro Nacional de Pesquisa e Conservação de Cavernas

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Resultados da Pesquisa

Agora exibindo 1 - 10 de 29
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    Species richness, occurrence and rarity of bats in Brazilian caves
    (2023-10-27) Barros, Jennifer S.; Bernard, Enrico
    Caves are among the most important roosts of hundreds of bat species worldwide. However, caves can be formed in different lithologies. Cave structure and characteristics, which are shaped by lithology, can, in turn, influence roost preferences for different bat species. Therefore, cave lithology and characteristics can help us to better understand why some bat species may be rare in some caves and common in others. Brazil is a continental country, rich in bat species (181 spp.), lithologies and caves (>23 000). However, only a small fraction of the known caves has been sampled for bats so far, with no emphasis on the role lithology may have. Based on a literature review and using data on bat occurrence, in this study, we investigated the influence of lithology on bat species richness and rarity in Brazilian caves. We evaluated 117 studies, including data from 552 caves, and updated the number of bat species occurring in Brazilian caves to 81. Species richness differed between lithologies: carbonate caves had higher species richness, whereas iron caves had lower species richness. Richness was positively related to carbonate caves and with cave size: the bigger the cave, the more species-rich it tends to be. Overall, caves in the Cerrado had the highest species richness, followed by Atlantic Forest, Caatinga caves and Amazonian caves. Thirteen species can be considered as primarily cave-dwelling species, recorded in 10%–20% of the caves. Rarity was common among primarily cave-dwelling species. Nearly 22% of the sampled caves harboured endangered species, reaching 53% of the species-richest caves. Our analysis provides a comprehensive baseline for bat fauna in different types of caves in Brazil. Even so, we strongly recommend the establishment of long-term monitoring of population trends for bats in Brazilian caves, which is necessary information but almost non-existing for the country.
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    Low-Cost 3D Reconstruction of Caves
    (2023) Teixeira, Joao Marcelo; Pimentel, Narjara; Barbier, Eder; Bernard, Enrico; Teichrieb, Veronica; Chaves, Gimena
    Caves are spatially complex environments, frequently formed by different shapes and structures. Capturing cave’s spatial complexity is often necessary for different purposes – from geological to biological aspects – but difficult due to the challenging logistics, frequent absence of light, and because the necessary equipment is prohibitively expensive. Efficient and low-cost mapping systems could produce direct and indirect benefits for cave users and policy-makers, enabling from non-invasive research of fragile structures (like speleothems) to new forms of interactive experiences in tourism, for example. Here we present a low-cost solution that combines hardware and software to allow capturing cave spatial information through RGB-D sensors and the later interpretation of the processed data. Our solution allows the navigation in a 3D reconstructed cave, and may be used to estimate volume and area information, frequently necessary for conservation or environmental licensing. We validated the proposed solution by partially reconstructing one cave in Northeastern Brazil. Although some challenges have to be overcome, our approach showed that it was possible to retrieve relevant information despite using low-cost RGB-D sensors.
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    Predation of a mustached bat, Pteronotus sp. (Mormoopidae), by an Amazon tree boa, Corallus hortulanus (Boidae), in the Brazilian Amazon
    (2023) Barbier, Eder; Pimentel, Narjara Tércia; Bernard, Enrico
    Several bat species use caves as roosts and some of these caves can harbor high concentrations of individuals. Such caves may represent opportunities for certain predators, benefiting from the concentration of potential prey. Here, we report the predation of a Pteronotus bat by a Corallus hortulanus in the Brazilian Amazon. On three occasions over a year, individuals of C. hortulanus were observed around a cave that harbors populations containing tens of thousands of bats. On one occasion, an individual of this snake species was observed preying on a Pteronotus sp. as it left the cave. Our record extends the known diet for C. hortulanus, documenting the predation of a mormoopid bat by this snake species for the first time. This record reinforces the need for longitudinal studies at sites with exceptional bat populations to gain a deeper understanding of the ecological predator-prey relationships involving this diverse group of mammals.
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    Ticket to ride: fungi from bat ectoparasites in a tropical cave and the description of two new species
    (2022-12-01) Carvalho, João Lucas Vitório; Lima, Joenny ; Barbier, Eder; Bernard, Enrico; Bezerra, Jadson Diogo Pereira ; Souza-Motta, Cristina
    Bat flies are obligate ectoparasitic dipterans that are highly specialised to bats and have apomorphic characteristics, such as absent or reduced wings, and specialised legs and claws, which contribute to their survival. They are often associated with fungi and harbour a fungal diversity that is still poorly understood. Fungi were found in association with the bat flies in a cave of the Caatinga dry forest in Brazil. In total, 43% of the captured bat flies were associated with fungi. Seventy-six flies were collected. DNA sequence analyses of 39 isolates showed that the isolates belonged to 13 species within nine genera, with 38 isolates belonging to Ascomycota and one isolate to Basidiomycota, and Aspergillus was the most frequently isolated genus. Most of the genera found have also been isolated from bat bodies and other substrates/hosts in caves in different regions of the world. Based on morphological and multi-locus phylogenetic analyses, two new species of Ascomycota were described: Allophoma brasiliensis sp. nov. and Pyrenochaetopsis cecavii sp. nov.
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    Streblid flies parasitizing cave bats in Carajás, Amazonia, with a new record for Brazil
    (2023) Barbier, Eder; Bernard, Enrico
    Streblid flies (Diptera: Streblidae) are hematophagous and highly specialized parasitic insects, found only on bats (Chiroptera). Caves are important roosts for bats but, despite harboring high bat richness, relatively few studies exist on the ecology and biology of streblid flies in cave environments, especially in Amazonia, the largest domain in northern Brazil, with >140 bat species and thousands of caves. To fill some of the gaps in the geographical distribution and interspecific relationships for streblid flies in the region, we sampled bats in six caves in Carajás National Forest, a protected area in Pará state (Brazil). Thirteen of the 14 streblid species found are new records for Carajás, with three new records for Pará state and two for the northern region of Brazil. Nycterophilia fairchildi was recorded for the first time in Brazil. Most streblids had host-specific behavior, however, N. fairchildi, Trichobius caecus, and T. johnsonae were less host-specific, parasitizing different Pteronotus bat species. The gregarious behavior of Pteronotus species and the spatial distribution of their colonies within the caves may be important factors in the flies’ exchange among congener hosts and deserve special attention in future studies. Furthermore, studies on ecological interaction networks between bats and their ectoparasitic flies in caves will be useful for a broader understanding of how this relationship is structured over time and space, as well as its impact on both bats and flies.
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    Big family, warm home, and lots of friends: Pteronotus large colonies affect species richness and occupation inside caves
    (2023-03-01) Barros, Jennifer S.; Bernard, Enrico
    Roosts are essential for the survival of most animals. Due to homothermic requirements, mammals are particularly dependent on roost quality and availability. Bats select their roosts in a species-specific way, likely related to species´ different physiological and adaptive needs. Unlike species whose individuals roost solitarily, roost selection is critical for bats forming large colonies due to the requirements for maintaining thousands of individuals in a single shelter. This is the case of Pteronotus (Mormoopidae), whose colonies reach hundreds of thousands of bats. Using captures, bioacoustics, and automated censuses, we evaluated how cave size, ceiling characteristics, environmental stability, temperature, and humidity influence the formation of exceptionally large colonies, species richness and composition in caves in north-eastern Brazil. We expected that colonies would be positively related to cave size and stability, internal cave selection would be species-specific, but larger and more environmentally stable caves would have higher richness. Pteronotus colonies were positively related to cave size, stability, and ceiling characteristics, and their presence strongly influenced cave temperature variation. Species richness was positively correlated to a cave stability index. Species other than Pteronotus preferred different climatic and ceiling characteristics. We detected an indirect influence of the large colonies of Pteronotus on the species richness and occupation inside caves. On the other hand, such caves favor species coexistence, as they offer a range of microenvironments, reducing niche overlap in their interior. Pteronotus gymnonotus and Pteronotus personatus are both key- and umbrella-species for cave ecosystems, stressing the need for specific conservation strategies in Brazil.
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    An Exceptionally High Bat Species Richness in a Cave Conservation Hotspot in Central Brazil
    (2021-07-09) Barros, Jennifer de Sousa; Bernard, Enrico; Ferreira, Rodrigo Lopes
    Caves are among the most used and important roosts for hundreds of bat species worldwide. However, caves remain some of the least known and most threatened environments globally. Documenting the richness of bat species in caves is important not only to draw attention to the uniqueness and relevance of these roosts, but it also contributes to the identification of priority sites for the conservation of bats and the cave fauna dependent upon them. Here, we assessed and described an exceptionally high bat richness in a group of caves in southeastern Tocantins, central Brazil. Inventories carried out in 19 caves resulted in seven families and 31 bat species, of which three were new regional records. Twelve caves were used by threatened and endangered bat species, eight had high diversity indices, and seven caves had high species richness, including one cave that may hold a world record with 26 bat species found inside. The variation in beta diversity is mainly due to species turnover, which indicates that protecting the largest possible number of caves would be ideal for the most efficient conservation of local bat assemblages. The sampled region stands out for its high potential for the conservation of endangered species, and we strongly recommend the full protection of 15 caves classified as a priority for conservation.
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    Estimates of insect consumption and guano input in bat caves in Brazil
    (2022-03-12) Pimentel, Narjara Tércia; da Rocha, Patrício Adriano; Pedroso, Mônica Aparecida; Bernard, Enrico
    Bat caves harbor exceptional populations of insectivorous bats. Those bats play an important role as insect suppressors and produce large quantities of guano, which is essential for maintaining cave ecosystems since entire highly specialized cave biotas may heavily rely on bat guano as their main energy input. Although ecologically relevant, few studies have estimated insect consumption and guano input in Neotropical bat caves. We provide estimates for five bat caves used by Pteronotus gymnonotus and P. personatus (Mormoopidae) in northeastern Brazil. Using a non-invasive automated system, we counted bats, then captured and weighted individuals to estimate insect consumption, and, with collectors and rulers, estimated the amount and speed of guano accumulation in cave sectors. Bat abundance varied between and within caves, up to 158,884 bats, indicating highly dynamic occupation patterns. Insect consumption varied from 0.6 to 2.5 g/bat for P. gymnonotus (~5 to 20% of their body weight) and 0.8 to 2.0 g/bat for P. personatus (~10 to 28% of their body weight). Guano deposition was spatially and temporally heterogeneous (from 0 to 738 g/m2/96h). Some caves showed a 15-cm increase in guano deposits on the cave floor in 7 months. Bulky guano deposits in those caves stressed the bat role as insect suppressors. The present study provides baseline quantitative data on the contributions of bats to cave ecosystems and valuable data for estimates of ecosystem services provided by bats.
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    Richness of Cladosporium in a tropical bat cave with the description of two new species
    (2022-03-04) Pereira, Mayara L. S.; Carvalho, João L. V. R.; Lima, Joenny M. S.; Barbier, Eder; Bernard, Enrico; Bezerra, Jadson D. P.; Souza-Motta, Cristina M.
    Caves are important roosts for hundreds of bat species worldwide. Such habitats frequently harbour rich and extremely specialised biotas; however, they remain among the least-studied places on Earth, particularly in the tropical region. The fungal richness in tropical caves in Brazil has recently been studied, and these surveys have reported a largely unexplored mycobiome, highlighting some bat caves as hotspots for fungal findings. During a speleomycological survey in a bat cave in the Caatinga dry forest in Brazil, 15 Cladosporium isolates were obtained from the air and ectoparasitic bat flies (Diptera: Streblidae) collected from the bat Pteronotus gymnonotus (Chiroptera: Mormoopidae). Based on morphological features and multi-gene (ITS rDNA, ACT, and TEF1) phylogenetic analyses, we reported eight Cladosporium species in this cave. Two new species, Cladosporium cavernicola and Cladosporium pernambucoense, were isolated from the cave air and have been formally described here. They, along with Cladosporium puris, Cladosporium subuliforme, and Cladosporium tenuissimum, were related to the Cladosporium cladosporioides species complex. Additionally, we recorded Cladosporium austrohemisphaericum, Cladosporium parahalotolerans, and Cladosporium sphaerospermum (C. sphaerospermum species complex). Our findings emphasise the large potential for new fungal species associated with caves and bats worldwide.
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    Living in the dark: Bat caves as hotspots of fungal diversity
    (2020-12-04) O. B. Cunha, Aline; D. P. Bezerra, Jadson; G. L. Oliveira, Thays; Barbier, Eder; Bernard, Enrico; R. Machado, Alexandre; M. Souza-Motta, Cristina; Sabrina Sarrocco
    Bat caves are very special roosts that harbour thousands of bats of one or more species. Such sites may hold an incredible “dark fungal diversity” which is still underestimated. We explored the culturable fungal richness in the air, on bats, and in the guano in a bat cave in Brazil’s Caatinga dry forest. Fungal abundance was 683 colony-forming units (CFU) in the guano, 673 CFU in the air, and 105 CFU on the bats. Based on morphological and phylogenetic analysis of ITS, LSU, and TUB2 sequences, fungal isolates of 59 taxa belonging to 37 genera in the phyla Ascomycota (28 genera, including Aspergillus, Penicillium, Cladosporium, and Talaromyces), Basidiomycota (eight genera, including Rhodotorula and Schizophyllum), and Mucoromycota (only Rhizopus) were identified. The fungal richness in the air was 23 taxa (especially Aspergillus taxa), mainly found at 15 m and 45 m from the cave entrance; on the bodies of bats it was 36 taxa (mainly Aspergillus taxa), especially on their wing membranes (21 taxa, nine of which were exclusively found in this microhabitat); and in guano 10 fungal taxa (especially Aspergillus and Penicillium) were found. The fungal richness associated with guano (fresh and non-fresh) was similar from bats with different eating habits (insectivorous, frugivorous, and haematophagous). Sampling effort was not sufficient to reveal the total fungal taxa richness estimated. Eight (21.6%) of the 37 genera and 17 (53.1%) of the 32 identified fungal species are reported for the first time in caves. Our results highlight bat caves in Brazil as hotspots of fungal diversity, emphasizing the need to protect such special roosts.