mciHabitat disturbance and fragmentation alter the diversity, spatial and temporal distribution of food and other resources, forcing animals to alter many aspects of their biology, including feeding ecology, population structure and territorial behavior, in order to survive. Golden-headed lion tamarins (Leontopithecus chrysomelas; GHLTs) are small arboreal primates, endemic to the Atlantic Coastal Rainforest of Southern Bahia and endangered because of the disappearance of their habitat. Although they need tall forest to fulfill their need for insects and tree holes for sleeping, most populations today survive in fragmented and disturbed areas. The survival of the species depends critically on increasing the area of protected forest, through forest linkage and corridor building. Currently, scientific data are virtually limited to populations in relatively continuous habitat, and data on factors that determine carrying capacity of forest habitats for GHLTs, and population dynamics, ecology and behavior of the species in different habitats, are scarce. This project intends to study the behavior and feeding ecology of GHLTs in fragmented areas and different forest habitats, in order to investigate the species’ response to forest fragmentation and disturbance, and provide basic information that is essential for the development of a conservation management plan. Using a combination of behavioral observation, vegetation analysis, nutritional and morphological analyses of food resources, fecal analysis and phenological follow-up, we investigate the ecological characteristics of forest types that are suitable for GHLTs, factors that determine diet choice, group range size and seasonal range use, how GHLTs alter their behavior in relation to differences in forest types, and their role as seed dispersers. The results will allow for evaluating the suitability of different forest types and fragments, and consequently the prioritizing of areas for conservation actions, the choice of areas for corridor building and suggestions for corridor structure.