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The bush dog (Speothos venaticus) is a small Neotropical canid. Although its distribution covers the entire Amazon basin, the occurrence of bush dogs in vast areas of the Amazon remains hypothetical. The records of bush dogs presented in this study reduce a large gap in the known distribution of the species in Central Amazonia and include the 1st documentation of the species from forest seasonally flooded by black water (Igapó). [ABSTRACT FROM AUTHOR]

Investigates the food items consumed by sympatric manned wolves, crab-eating foxes and haory foxes in the Cerrado biome of central Brazil to determine overlap among their diets. Home ranges and spatial segregation among the canids; Determination of the importance of each food item through relative frequency; Habitat use by the canids.

We tested the hypothesis that microhabitat variables, abundance of terrestrial rodents, and microhabitat selection patterns of terrestrial rodents vary between the cool-dry and warm-wet season in the Atlantic forest of Brazil. We selected variables associated with ecological factors potentially important to terrestrial rodents (physical structure of litter and woody debris, and arthropod availability) and established 25 small, independent sampling units covering 36 ha of a homogenous, mature Atlantic forest patch. Litter humidity and height, amount of small woody debris, arthropod availability, and terrestrial rodent abundance increased, whereas the quantity of large woody debris decreased in the warm-wet season. Greater spatial segregation among terrestrial rodents also was observed in this season, especially between morphologically similar species. The distribution of 3 of the 4 most common terrestrial rodents was influenced by microhabitat variables in at least 1 of the seasons, and these species also differed in their pattern of microhabitat selection between seasons. In general, the amount of small woody debris and litter humidity were more important for the microscale distribution of terrestrial rodents in the cool-dry season, whereas in the mild warm-wet season species distributions were associated with food availability or were not clearly influenced by the measured variables. The patterns of microhabitat selection by 3 common terrestrial rodents, which were associated with features that characterize old-growth forest, may be responsible for their vulnerability to forest fragmentation. [ABSTRACT FROM AUTHOR]

Animals should use habitats that increase their chances of survival and reproductive output; thus, information on habitat use can be useful both from an ecological and a conservation perspective. Using global positioning system tracking collars, we studied habitat use by a pair of Chrysocyon brachyurus (maned wolves) living in a cerrado-Atlantic forest transition zone in Brazil. During our study, the female had a litter of pups, and we were able to evaluate how reproduction affected habitat use. To investigate habitat use, we mapped our telemetry fixes onto vegetational and geographical data obtained from satellite images of our study site. We investigated habitat use by maned wolves in relation to vegetation and land cover, proximity to buildings, proximity to roads, elevation, and distance to water sources. Maned wolves showed a strong preference for rocky fields, which are a subhabitat of cerrado, and a strong avoidance of Atlantic rain forest. Maned wolves also were associated significantly and positively with buildings and roads at night, likely because of supplemental feeding and ease of locomotion. Elevation was confounded with habitat type and the location of supplemental feeding; therefore, no firm conclusions could be drawn about this factor. The female remained ≤250 m from water when she was lactating. Although maned wolves can be behaviorally flexible in terms of habitat use, they show a strong preference for open habitats such as cerrado that is especially pronounced during a reproductive phase. [ABSTRACT FROM AUTHOR]

This study aims to elucidate the social system of the wild cavy (Cavia aperea), the feral ancestor of the domestic guinea pig, whose behavior under natural conditions is almost unstudied. Therefore a population of C. aperea was investigated for a 6-month period in its natural habitat in southeastern Brazil. The animals' space use was examined via radiotelemetry, social interactions were recorded using direct observations, and genetic relationships were analyzed via DNA fingerprinting. Additionally, the distribution of plant cover, fixed resources, and predation risk was recorded to investigate the impact of different ecological factors on evolution of the social system. In the study period, a low population density was detected and a strong predation pressure existed, which resulted in a high mortality rate of C. aperea. Spatial distribution of wild cavies was strongly associated with areas of dense ground vegetation. Within these areas, small groups consisting of 1 male and 1-2 females occupied stable home ranges that overlapped only slightly with home ranges of adjacent groups. Social interactions were restricted mainly to individuals of the same group, and initial analyses of paternity indicate that the females' offspring were sired by the respective group male. The social system and spatial organization of C. aperea are regarded as adaptations to high predation pressure because in dense vegetation small group size reduces the risk of detection by predators. Moreover, habitat use, social interactions, and paternity point to a single-male system in this low-density population of wild cavies. [ABSTRACT FROM AUTHOR]