Abstract # 236:

Scheduled for Saturday, August 19, 2006 01:30 PM-01:45 PM: Session 23 (Regency East #2) Oral Presentation

Food Selection by Colobus guereza in Kakamega Forest, Kenya

C. B. Mowry1, E. S. Dierenfeld2 and P. J. Fashing3,4
1Berry College, Dept. of Biology, Box 430, Mt. Berry, GA 30149, USA, 2Saint Louis Zoo, 3Pittsburgh Zoo & PPG Aquarium, 4Columbia University
     We examined the influence of macronutrients, minerals, and secondary compounds on food choices by black and white colobus monkeys (Colobus guereza) inhabiting the Kakamega Forest, Kenya. Pearson correlations and t-tests were used to compare dietary selection to phytochemical content. Protein was the primary factor determining leaf choice, with leaves eaten ? ~14% protein dry matter (p<0.01). However, a finer grade analysis considering the selection ratios of only those items eaten revealed that fiber played a much greater role in negatively influencing the rates at which different items were eaten relative to their abundance in the forest (acid detergent fiber: p=0.001; neutral detergent fiber: p=0.003). Most minerals did not appear to influence leaf choice, with a notable exception being a strong selectivity for zinc (p<0.05). Guerezas avoided most leaves high in secondary compounds (e.g., comparing condensed tannins in eaten vs. uneaten leaves p=0.037), though their top food item (Prunus africana mature leaves) contained some of the highest condensed tannin concentrations of any leaves in their diet. We also compared Kakamega with other Paleotropical rain forests in which colobine biomass can be predicted by the protein-to-fiber ratio in mature leaves. Kakamega data fit the pattern well in that Kakamega features the second highest mature leaf protein-to-fiber ratio as well as the second highest colobine biomass of the 8 rain forests for which the relevant data are available.