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Bat Communities (bat + community)
Selected AbstractsScale-dependent responses to forest cover displayed by frugivore batsOIKOS, Issue 11 2008Naiara Pinto Despite vast evidence of species turnover displayed by Neotropical bat communities in response to forest fragmentation, the exact shape of the relationship between fragment area and abundance for individual bat species is still unclear. Bats' ample variation in diet, morphology, and movement behaviour can potentially influence species' perception of the landscape. Thus, studies describing fragment area at a single spatial scale may fail to capture the amount of forest available from the perspective of individual bat species. In the present paper, we study the influence of forest cover on bats inhabiting a fragmented forest in Mexico, focusing on some of the most common frugivore species: Artibeus jamaicensis, Carollia spp. (C. brevicauda/C. perspicillata) and Sturnira spp. (S. lilium/S. ludovici). We quantified forest cover at scales ranging from 50 to 2000,m, and measured the influence of forest cover on bat capture success, a surrogate for abundance. The three species displayed positive and significant scale-dependent associations with forest cover. Abundance of A. jamaicensis increased with forest cover measured at scales ranging between 500 and 2000,m, while Carollia spp. responded more strongly to variation in forest cover measured at scales 100,500,m. For Sturnira spp., abundance was a function of presence of creeks near mist-netting sites, and amount of secondary forest present at a 200,m scale. The observed variation in responses to forest cover can be explained in light of interspecific differences in diet, home range, and body size. Our results illustrate a method for measuring the effect of forest fragmentation on mobile species and suggest that changes in abundance in fragmented landscapes emerge from the interaction between species' traits and landscape structure. [source] Density compensation in New World bat communitiesOIKOS, Issue 2 2000Richard D. Stevens Understanding the role of competitive interactions in shaping the structure of communities has been one the most unrelenting challenges to ecology. Traditionally, competitive interactions were assumed to be the most important agent of deterministic structure, with overdispersed morphological patterns based on body size and trophic status as their hallmark. However, models of community organization based solely on morphology have yielded only equivocal results for many taxa. Fortunately, morphological patterns may not be the only indications of competitively induced deterministic structure. Herein, we explore the degree to which the structure of five feeding guilds (aerial insectivores, frugivores, gleaning animalivores, molossid insectivores, and nectarivores) from 15 New World bat communities reflects density compensation. Nonrandom associations between abundance and morphological distance were detected in five communities, in three feeding guilds, and with respect to four competitive scenarios. Nonetheless, patterns consistent with the hypothesis of density compensation were neither pervasive nor consistent in New World bat communities. Competitively induced community structure may exist under only narrow temporal and environmental conditions, and may not be characteristic of organization in most situations. [source] Effects of different secondary vegetation types on bat community composition in Central Amazonia, BrazilANIMAL CONSERVATION, Issue 2 2010P. E. D. Bobrowiec Abstract The process of secondary succession on degraded lands in the Amazon depends on their land-use histories. In this scenario, little is known about how animal communities respond to different types of secondary vegetation in the region. We examined the effects of abandoned cattle pasture, Vismia - and Cecropia -dominated regrowth on the abundance of bat species and community composition in the Central Amazon, Brazil, based on 11 netting sites and on landscape characteristics. We captured 1444 bats, representing 26 species and two families (Phyllostomidae and Mormoopidae). Among the six most-captured Phyllostomidae bats, Sturnira lilium and Sturnira tildae had significantly higher capture rates in abandoned pasture, while Rhinophylla pumilio predominated in both Vismia - and Cecropia -dominated regrowth. An hybrid multidimensional scaling ordination revealed significant differences in the bat community among the three types of secondary vegetation. Phyllostominae bats were more common and richer in the less-disturbed areas of Cecropia -dominated regrowth, while Stenodermatinae species were more captured in abandoned pastures. Our results suggest that the type of secondary vegetation, together with its land-use history, affects bat community composition in the Central Amazon. The Phyllostominae subfamily (gleaning animalivores) was habitat selective and disappeared from areas experiencing constant disturbances. On the other hand, Stenodermatinae frugivorous bats often used and foraged in altered areas. We suggest that secondary vegetations in more-advanced successional stages can be used to augment the total area protected by forest conservation units. [source] | ||||||||||