Resumo
We evaluated the structure of a community of frugivorous bats using composition and abundance patterns, niche amplitude and food overlap of these animals in four Atlantic Forest fragments, each one exposed to different conservation realities. For twelve months, we captured six bat species and found the seeds of 13 species of pioneering plants in 158 fecal samples. The most abundant bat species were Artibeus planirostris (25.4%), Artibeus lituratus (24.1%) and Carollia perspicillata(23.9%). Only one fragment (Fazenda Unida), the most conserved area, exhibited a significantly different composition and abundance of species. We found low trophic niche amplitude values (<0.60), associated to high food overlaps. Our results suggest that bats can adjust their foraging strategy to deal with food availability variations. By favoring pioneering plant species, the fragmentation process noted of the studied areas creates an attractive environment for bats more tolerant to this type of disturbance. The sampled areas represent important secondary forest remnants in southern Brazil that require attention to avoid an even greater loss of bat diversity.
Assuntos
Animais , Cadeia Alimentar , Quirópteros/anatomia & histologia , Quirópteros/crescimento & desenvolvimentoResumo
We evaluated the structure of a community of frugivorous bats using composition and abundance patterns, niche amplitude and food overlap of these animals in four Atlantic Forest fragments, each one exposed to different conservation realities. For twelve months, we captured six bat species and found the seeds of 13 species of pioneering plants in 158 fecal samples. The most abundant bat species were Artibeus planirostris (25.4%), Artibeus lituratus (24.1%) and Carollia perspicillata(23.9%). Only one fragment (Fazenda Unida), the most conserved area, exhibited a significantly different composition and abundance of species. We found low trophic niche amplitude values (<0.60), associated to high food overlaps. Our results suggest that bats can adjust their foraging strategy to deal with food availability variations. By favoring pioneering plant species, the fragmentation process noted of the studied areas creates an attractive environment for bats more tolerant to this type of disturbance. The sampled areas represent important secondary forest remnants in southern Brazil that require attention to avoid an even greater loss of bat diversity.(AU)
Assuntos
Animais , Quirópteros/anatomia & histologia , Quirópteros/crescimento & desenvolvimento , Cadeia AlimentarResumo
Plantation forests are becoming increasingly important elements of tropical human-modified landscapes, yet their conservation value for many animal taxa remains little explored. We compared phyllostomid bat assemblages in semideciduous forest fragments in Brazilian Cerrado with those of eucalypt plantations (Eucalyptus spp.). Specifically, we assessed differences in species richness, diversity, abundance, and species composition between habitat types and evaluated phyllostomid bat responses with respect to a variety of landscape characteristics and local-scale variables. Bats were sampled with mist nets in four replicates each of Eucalyptus plantations and fragments of native Cerrado. Of the total of 209 individuals captured, 75 were caught in plantations and 134 in native forest areas. Cerrado assemblages were characterized by higher species richness, diversity, and evenness compared to those in Eucalyptus plantations. Gleaning animalivorous phyllostomids seem to be most sensitive to plantation forests, as they were not captured in this habitat. Non-metric multidimensional scaling indicated no strong separation between habitat types and there were no significant differences in species composition based on an analysis of similarities. The proportion of forest cover (both Cerrado and Eucalyptus) in the landscape was the only landscape-scale variable which had a significant influence on species composition. In contrast, species composition was unrelated to geographical distance between forest fragments. A generalized linear mixed effects model for the three most frequently captured species (Carollia perspicillata, Artibeus planirostris, Platyrrhinus lineatus) only showed significant differences in abundance for Artibeus planirostris, the species being more abundant in native Cerrado. Our results demonstrate the impoverishment of bat assemblages in Eucalyptus plantations and highlight the importance of examining the effects of habitat conversion at the[...]
Assuntos
Animais , Ecossistema , Eucalyptus , Pradaria , Quirópteros , FlorestasResumo
Plantation forests are becoming increasingly important elements of tropical human-modified landscapes, yet their conservation value for many animal taxa remains little explored. We compared phyllostomid bat assemblages in semideciduous forest fragments in Brazilian Cerrado with those of eucalypt plantations (Eucalyptus spp.). Specifically, we assessed differences in species richness, diversity, abundance, and species composition between habitat types and evaluated phyllostomid bat responses with respect to a variety of landscape characteristics and local-scale variables. Bats were sampled with mist nets in four replicates each of Eucalyptus plantations and fragments of native Cerrado. Of the total of 209 individuals captured, 75 were caught in plantations and 134 in native forest areas. Cerrado assemblages were characterized by higher species richness, diversity, and evenness compared to those in Eucalyptus plantations. Gleaning animalivorous phyllostomids seem to be most sensitive to plantation forests, as they were not captured in this habitat. Non-metric multidimensional scaling indicated no strong separation between habitat types and there were no significant differences in species composition based on an analysis of similarities. The proportion of forest cover (both Cerrado and Eucalyptus) in the landscape was the only landscape-scale variable which had a significant influence on species composition. In contrast, species composition was unrelated to geographical distance between forest fragments. A generalized linear mixed effects model for the three most frequently captured species (Carollia perspicillata, Artibeus planirostris, Platyrrhinus lineatus) only showed significant differences in abundance for Artibeus planirostris, the species being more abundant in native Cerrado. Our results demonstrate the impoverishment of bat assemblages in Eucalyptus plantations and highlight the importance of examining the effects of habitat conversion at the[...](AU)