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Uezu A.,IPE Institute for Ecological Research | Metzger J.P.,University of Sao Paulo
Biodiversity and Conservation | Year: 2011

Patch size, isolation, and vegetation structure are expected to strongly affect species persistence in fragmented landscapes, particularly for those with <30% of native habitat remaining. Those influences should be modulated by species characteristics, resulting in complex relationships. In order to investigate how species, habitat structure and landscape factors are related and how they affected species persistence, we studied bird communities in a fragmented Atlantic Forest region. Patch size strongly affected species richness and population abundances. However, some functional groups were more affected than others, particularly endemic and understory insectivores, species that are near the limits of their geographical distribution, those using few forest types, and those with their center of abundance in high altitude tropical forests. The effect of vegetation structure was mainly at the species level, reflecting specific responses to habitat quality. The importance of landscape variables varies according to the species group. For the most affected ones, which usually have low dispersal capacity, patch size and quality were the most relevant factors, whereas patch isolation was associated with the richness of groups with more generalist species. This pattern is due to the limited structural connectivity in the study region, composed of low matrix permeability (e. g. pastures and sugar cane), which isolate the most affected species, making them more dependent on local factors. In such a fragmented landscape, the largest patches should be prioritized for conservation purposes, as they aggregate the most vulnerable species and present the highest alpha diversity. Landscape management, as such, should also reconnect large fragments through corridors or matrix improvements, promoting better conditions for long-term persistence of the most affected species. © 2011 Springer Science+Business Media B.V.

Bowler M.,University of St. Andrews | Bowler M.,Behavioral Ecology and Sociobiology Unit | Knogge C.,IPE Institute for Ecological Research | Heymann E.W.,Behavioral Ecology and Sociobiology Unit | Zinner D.,German Primate Center
International Journal of Primatology | Year: 2012

Researchers have described multilevel societies with one-male, multifemale units (OMUs) forming within a larger group in several catarrhine species, but not in platyrhines. OMUs in multilevel societies are associated with extremely large group sizes, often with >100 individuals, and the only platyrhine genus that forms groups of this size is Cacajao. We review available evidence for multilevel organization and the formation of OMUs in groups of Cacajao, and test predictions for the frequency distribution patterns of male-male and male-female interindividual distances within groups of red-faced uakaris (Cacajao calvus ucayalii), comparing year-round data with those collected at the peak of the breeding season, when group cohesion may be more pronounced. Groups of Cacajao fission and fuse, forming subgroup sizes at frequencies consistent with an OMU organization. In Cacajao calvus ucayalii and Cacajao calvus calvus, bachelor groups are also observed, a characteristic of several catarrhine species that form OMUs. However, researchers have observed both multimale-multifemale groups and groups with a single male and multiple females in Cacajao calvus. The frequency distributions of interindividual distances for male-male and male-female dyads are consistent with an OMU-based organization, but alternative interpretations of these data are possible. The distribution of interindividual distances collected during the peak breeding season differed from those collected year-round, indicating seasonal changes in the spatial organization of Cacajao calvus ucayalii. We suggest a high degree of flexibility may characterize the social organization of Cacajao calvus ucayalii, which may form OMUs under certain conditions. Further studies with identifiable individuals, thus far not possible in Cacajao, are required to confirm the social organization. © 2012 The Author(s).

Mangini P.R.,IPE Institute for Ecological Research | Mangini P.R.,Brazilian Institute for Conservation Medicine TRIADE | Mangini P.R.,IUCN SSC Tapir Specialist Group TSG | Mangini P.R.,IUCN SSC Wildlife Health Specialist Group WHSG | And 7 more authors.
Integrative Zoology | Year: 2012

Tapirs have unique nutritional needs, as well as anatomical, physiological, behavioral and ecological adaptations that must be considered when managing their health, both in the wild and in captivity. Information about how tapirs live in their natural habitats can provide crucial knowledge to prevent many of the health problems found in captivity such as infectious and parasitic diseases, reproductive issues and nutritional and behavioral disorders. Likewise, proper management in captivity can significantly contribute to in situ conservation programs. Conservation medicine is a science created to address the global health crisis that jeopardizes biodiversity causing imbalances among ecosystem, human, animal and vegetal health. In this context, common threats to tapir health and conservation, such as isolated and small populations surrounded by human activity, chemical pollution, domestic animals and their pathogenic agents, need to be better understood. This manuscript provides information about the health of tapirs both in captivity and in the wild and aims to encourage tapir conservationists worldwide to gather information about pathogen and disease dynamics and manifestation, as well as implications for tapir conservation.

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