Abstract # 5:

Scheduled for Thursday, August 17, 2006 10:15 AM-10:30 AM: Session 1 (Regency East #1) Oral Presentation

The Effect of Habitat Fragmentation on Golden-Headed Lion Tamarin Presence in Southern Bahia, Brazil

B. E. Raboy1,2, N. A. Saraiva1, N. Cardoso2, L. G. Neves2, G. R. Santos2, J. Ballou1 and P. Leimgruber1
1Smithsonian National Zoological Park, Department of Conservation Biology, 3001 Connecticut Ave NW, Washington, DC 20008, USA, 2Instituto de Estudos Socioambientais no Sul da Bahia
     The development of effective conservation strategies for endangered golden-headed lion tamarins (Leontopithecus chrysomelas; GHLTs) relies on understanding the spatial distribution of forest fragments, their degree of connectivity, and the presence of GHLTs within these fragments. An understanding of population trends and the threats to GHLTs associated with different environments is also important. We used Geographic Information Systems to characterize the landscape structure of the remaining fragmented forests of Southern Bahia, Brazil. Using logistic regression, we tested the hypothesis that GHLT presence is related to fragment size and shape, habitat, amount of core area, climate, and proximity to neighboring fragments. To measure GHLT presence, we conducted surveys across the species range, interviewing people regarding the presence of GHLTs in 70 study fragments. Survey results indicated a potential reduction of 15% of the range in the last 13 years, in an area with extensive cattle ranching and extremely small, isolated fragments. Fragments in this region averaged approximately 142 ha (SD = 145.6). Fragment size across the range strongly predicted GHLT presence, with larger fragments more likely to contain GHLTs (p < 0.001). Core area, habitat type, climate and distance to nearest neighbors were not related to GHLT presence. Our study highlights the importance of preserving larger forest tracts, and emphasizes the speed at which local extinction can occur for arboreal species resulting from severe forest fragmentation.