Santa Clara University

Department of Anthropology Winter Seminar

March 7, 2012

5-6pm, Kennedy Commons

Ecological and historical perspectives on Bornean orangutan populations

Dr. Andy Marshall

Department of Anthropology

University of California - Davis

Understanding the factors that influence variation in orangutan population dispersion in space and time would both enhance our understanding of orangutan socioecology and contribute meaningfully to the conservation of this threatened taxon. We use data from a six year study of a population of Western Bornean Orangutans (Pongo pygmaeus wurmbii) at Gunung Palung National Park, West Kalimantan, Indonesia to test hypotheses about the role of food resources (and different classes thereof) in determining orangutan dispersion across space and over time. We assessed orangutan population dispersion across seven distinct tropical rainforest types (spanning lowland peat swamp to montane forest) using direct observations of orangutans on fourteen survey transects. The results support the hypotheses that orangutan populations at Gunung Palung partially buffer themselves against resource scarcity by switching habitats, that population movements are best explained by the abundance of preferred foods, and that peat swamp forests serve as “fallback habitats”. Conservation implications of these results will be discussed.

Refreshments will be provided