PARENT SESSION
Contributed Oral Session 126: Mammal Ecology: Management, Reproduction, and Food Webs
Thursday, August 11, 8:00 AM - 11:30 AM, Meeting Room 524 C, Level 5, Palais des congrès de Montréal
Do nutrition, parasitism, and stress have synergistic effects on red colobus populations living in forest fragments?
Chapman, Colin*,1, 2, Wasserman, Michael3, Gillespie, Thomas4, Speirs, Michaela1, Ziegler, Toni5, 1 Anthropology Department & McGill School of Environment, Montreal, Quebec, Canada2 Wildlife Conservation Society, Bronx, New York, USA3 Department of Environmental Science, Policy, and Management, Berkeley, California, USA4 Department of Veterinary Pathobiology, Urbana, Illinois, USA5 National Primate Research Center, Madison, Wisconsin, USA
ABSTRACT- A fundamental issue in ecology is identifying factors determining animal density, and the importance of this issue has increased with the need to develop informed management plans for endangered species. Since 1995, we have been studying the colobus populations inhabiting a series of forest fragments outside of Kibale National Park, Uganda. These are community-owned fragments, and different fragments have different histories of land use. This setting and the knowledge of how each population has changed offers a natural experiment, where it is possible to relate patterns of population change to nutrition, disease, and stress profiles. Thus, the objective of this study was to use this setting to examine if nutritional status, parasitism, and stress (indexed by fecal cortisol) have synergistic effects on red colobus (Piliocolobus tephrosceles) that may influence their abundance. We found that an increase in deforestation was related to an increase in nematode prevalence. As deforestation increased, the variance in cortisol level increased; and an increase in nematode prevalence was related to the variance in cortisol levels. The observed variance in cortisol may reflect variation in stress among individuals within the dominance hierarchy. Dominant animals will have access to the choice foods, and may not be physiologically stressed and therefore less susceptible parasite infections than subordinates. Overall, 68% of the variance in change in red colobus density could be attributed to changes in food tree density and nematode prevalence.
Key words: primates, Africa, folivore, nematodes