We determined for the first time how different types of land use affect the perceptual range of a species, using as model organisms two neotropical marsupials endemic to the Atlantic Forest in Brazil (Philander frenatus and Didelphis aurita). We released and tracked the movements of 196
individuals in three types of land use commonly found in fragmented landscapes: manioc plantation, mowed pasture and abandoned pasture. We also determined how orientation to the nearest forest fragment is affected by distance to the fragment, wind speed, body mass and sex using a model selection approach. The type of land use affected check details the perceptual ranges of both marsupials. The estimated perceptual ranges for P. frenatus and D. aurita were 100 and 200 m in the mowed pasture, respectively, 50 and <30 m in the abandoned pasture and 30 and 50 m in the plantation. The orientation of both species decreased with increasing distance to the fragment, but for D. aurita orientation also increased with the wind speed and body mass. These results agree with previous studies depicting a general pattern of increased perceptual range with lower vegetation obstruction in the matrix and larger body mass and wind speed, depending on the use of visual versus click here olfactory cues by animals. Our findings allow more realistic estimates of
functional connectivity in fragmented landscapes based on basic information on the biology of each species and the type of matrix. “
“We studied the social organization, use of foraging habitat, roost switching and diet of the sucker-footed bat Myzopoda aurita in south-eastern Madagascar. All 138 bats caught were males, 18 of which were selected for radio-tracking.
The areas individual bats used for foraging varied between 7 and 108 ha (100% minimum convex polygon). Bats foraged close the roost for the first hour after emergence, then travelled up to 1.8 km away. Compositional analysis revealed that they selected coffee plantations, MCE公司 degraded humid forest and wooded grassland more than any other habitats. All 133 roosts located consisted of the partially unfurled leaves of Ravenala madagascariensis and housed between nine and 51 individuals. Bats changed roosts every 1–5 days. Their diet comprised mainly of Lepidoptera and Coleoptera. No ectoparasites were observed. Myzopoda aurita is one of the few mammals endemic to Madagascar that uses disturbed patches of vegetation and is not therefore threatened by deforestation, although it may be affected by loss of roosts for building materials. The search for females continues. “
“In the extensive geographical distribution of the common dolphin, several morphotypes of uncertain taxonomic status, identified by the relative length of their rostra, have been established.