BIOLOGIA SUBTERRÂNEA
URI permanente para esta coleçãohttps://bdc.icmbio.gov.br/handle/cecav/3
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Item 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 LopesCaves 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.Item 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, EnricoBat 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.Item Análise de relevância de cavernas: uma revisão da IN 02/2017 sob a perspectiva dos morcegos(2020-11) Barros, Jennifer; Da Cunha Tavares, Valeria; Henrique Dias-Silva, Leonardo; Milagres, AugustoA relação entre várias espécies de morcegos e ecossistemas cavernícolas é altamente especializada, complexa e frágil. Comunidades de invertebrados cavernícolas são, frequentemente, dependentes do guano dos morcegos para sua sobrevivência, assim como os próprios morcegos dependem também destes abrigos para atividades sociais, proteção, descanso e reprodução. No Brasil, espécies associadas a cavernas tornaram-se mais susceptíveis a impactos decorrentes da destruição de seus abrigos, principalmente após alterações na legislação que flexibilizaram a proteção desses ambientes. A atual legislação determina que cavernas inseridas em áreas passíveis de licenciamento ambiental devem passar por um processo de classificação quanto ao seu grau de relevância. Estas regras estão incluídas na Instrução Normativa 02/2017 do Ministério do Meio Ambiente. Avaliamos aqui as disposições na IN 02/2017 considerando o grupo dos morcegos como foco específico, e considerando a clareza, objetividade, e aplicabilidade prática da normativa, bem como pontos frágeis e critérios subjetivos que necessitam de modificações. Identificamos trechos cuja redação é subjetiva, vaga ou imprecisa, tornando alguns dos critérios apontados para a designação de relevância problemáticos quando analisados sob o enfoque do grupo dos morcegos. Sugerimos que a IN passe por extensa atualização, com alterações de redação, exclusão de alguns critérios (e.g., espécies com função ecológica importante; troglóxenos obrigatório) e inclusão de outros (e.g., presença de fêmeas grávidas e filhotes).Item New records, potential distribution, andconservation of the Near Threatened cave batNatalusmacrourusin Brazil(2017-02-16) DELGADO-JARAMILLO, MARIANA; BARBIER, EDER; BERNARD, ENRICOSpecies with specific roosting, foraging or breeding requirements are particularly vulnerable to habitat loss and degradation. For bats, the availability and environmental condition of caves can be a limiting factor. The cave specialist Natalus macrourus (formerly Natalus espiritosantensis) is categorized as Near Threatened on the IUCN Red List but as Vulnerable in Brazil, based on a projected population reduction and a decline in its area of occupancy, extent of occurrence and/or quality of habitat. There is a lack of knowledge about the species’ distribution, natural history and ecology, information that is required for conservation. Using new occurrence data and potential distribution modelling we evaluated the distribution of N. macrourus in Brazil, analysed pressures on and threats to the species, and assessed the species’ conservation needs. Natalus macrourus is positively associated with areas with higher probability of cave occurrence and negatively associated with areas of high variation in mean daily temperature and mean annual rainfall. Areas with high environmental suitability for N. macrourus correspond to only 3% of the potential distribution modelled. We estimate that the species has already lost 54% of its natural habitat and that there is < 35% of habitat remaining in areas with high environmental suitability. We calculated that approximately half of the caves in areas with high environmental suitability are < 5 km from mining operations and only 4% of the species’ potential distribution lies within protected areas. Given the strong association of N. macrourus with caves, it is important to protect these habitats, and we recommend that caves where the species is present should receive immediate protection.Item Mobility of bats between caves: ecological aspects and implications for conservation and environmental licensing activities in Brazil(2021-08-17) Leal, Edson Silva Barbosa; Bernard, EnricoBats are highly mobile animals, moving rapidly over long distances. Detecting such movements is challenging, especially in cave areas, a commonly-used roost by bats. Brazil has a large number of caves and bat species, but details on bat mobility among caves is still poorly documented there. Such monitoring provides insights on the structuring and conservation of cave-dwelling communities, with possible legal implications for the environmental licensing in Brazil. Based on marking (2,490 bats captured; 2,142 marked) and recapture (35 events; 14 extra-site), here we present data on the mobility of mormoopid bats between two bat caves 15 km apart in northeastern Brazil. Sexual segregation between caves may explain mobility: one cave is likely a maternity roost; the other is a satellite cave used for copulae. Nomadic behavior due to seasonal distribution of resources in the semi-arid Northeastern Brazil cannot be ruled out. Based on the distance between the two caves, bats could potentially forage over an area of ~170,000 hectares, in a wider use of the landscape. Our data have implications for the conservation of bat species and their roosts, and contribute to a more evidence-based discussion of key concepts governing the environmental licensing of mining activities in Brazil.Item An exceptionally high bat species richness in a cave conservation hotspot in Central Brazil(2021-06) Ferreira, Rodrigo Lopes; de Sousa Barros, Jennifer; Bernard, EnricoCaves 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.- Inside or out? Cave size and landscape effects on cave-roosting bat assemblages in Brazilian Caatinga caves(2020-04-08) Carlos Vargas-Mena, Juan; Cordero-Schmidt, Eugenia; Rodriguez-Herrera, Bernal; A. Medellín, Rodrigo; de Medeiros Bento, Diego; M. Venticinque, Eduardo; Jorge OrtegaCave bats have an intimate association with their roosts. Size, structural heterogeneity, and microclimatic conditions are traits of caves known to affect the structure of these assemblages. The effects of the natural and anthropogenic landscape factors around caves on the structure of these assemblages are poorly known, especially in areas with large cave clusters. We assessed the effects of cave size and surrounding landscape attributes on the richness and species composition of cave-roosting bats in 13 caves distributed in two landscapes with large cave clusters in Caatinga dry forests, Brazil. In a 1-km buffer around caves, we obtained 13 internal cave and external landscape variables. Candidate univariate models using generalized linear models were constructed and the Akaike information criterion was used for model selection. The cave size model explained richness and variance in the species composition; larger caves tended to have greater richness and assemblage composition varied depending on the cave size, hence affecting the occurrence of certain species, some of conservation concern (Natalus macrourus, Furipterus horrens). The cave connectivity model affected only the richness; caves located in denser cave clusters had higher richness likely attributed to movement of bats among caves by a more diverse array of species. Both environmental and anthropic variables affected species composition, but differently depending of the landscape context of cave location (protected versus nonprotected area). The extent these landscape variables affected the species composition was due to species-specific responses, and observed in the mean colony sizes of the species shared between the cave systems. All the landscape variables that we tested affected the structuring process of cave-roosting bats assemblages, and evidences that variables found in disturbed karstic landscapes also affect the structure of the assemblage (e.g., large colonies of vampire bats). However, the ubiquitous effect of cave size on both richness and species composition reinforces the critical importance of the roost in the life of these flying mammals.
Item The bats of Rio Grande do Norte state, northeastern Brazil(Biota Neotropica, 2018-04-16) Vargas-Mena, Juan Carlos; Pereira, Kleytone Alves; Barros, Marília Abero Sá; Barbier, Eder; Schmidt, Eugenia Cordero; Lima, Sergio Maia Queiroz; Herrera, Bernal Rodríguez; Venticinque, Eduardo MartinsItem Sobre Quiropteros (Emballonuridae, Phyllostomidae, Natalidae) de duas cavernas da Chapada Diamantina, Bahia, Brasil(Iheringia Serie Zoologia, 1999) Gregorin, Renato; Mendes, Liana de FigueiredoItem Bats of the state of Minas Gerais, southeastern Brasil(Chiroptera Neotropical, 2010-07) Tavares, Valéria da C.; Aguiar, Ludmilla M. de S.; Perini, Fernando A.; Falcão, Fábio C.; Gregorin, Renato