Abstract # 1983 Event # 240:

Scheduled for Saturday, August 19, 2006 02:30 AM-02:45 AM: Session 23 (Regency East #2) Oral Presentation


FORAGING STRATEGIES OF PALE-ARMED HIMALAYAN LANGURS (Semnopithecus entellus schistaceus), LANGTANG NATIONAL PARK, NEPAL

K. Sayers and M. Norconk
Kent State University, School of Biomedical Sciences, Program in Biological Anthropology, Kent, OH 44242-0001, USA
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     Himalayan gray langurs inhabit among the most marginal habitats of all nonhuman primates, and little is known about their foraging behavior. We present ecological, ranging, and feeding scan data from a 16-month (2002-2004) field study of two monkey troops ranging between 3000 and 4000 m elevation in Langtang National Park, Nepal. Phenology records indicate extreme seasonality in plant productivity, with exceptionally low abundance in winter, increasing abundance in spring and monsoon, and a reduction in fall. Daily path lengths differed significantly between seasons (Kruskal-Wallis; p< 0.001), with the longest in winter (mean = 2.26 ± 1.13 km) and the shortest in monsoon (mean = 0.57 ± 0.29 km). Winter was characterized by reliance on leaf buds, ripe fruit, evergreen mature leaves, bark, and roots. Deciduous young leaves made up the plurality of the diet in spring, and deciduous mature leaves in the monsoon and fall. Using the annual phenology sample, the strongest positive Spearman correlations (p< 0.001) between abundance and consumption were for young leaves and ripe fruit. In addition, significant negative correlations were detected between mature leaf consumption and the abundance of unripe fruit (p< 0.01) and leaf buds (p< 0.05). Seasonal changes in diet breadth provide qualitative support for the classical prey model from optimal foraging theory. Supported by L.S.B. Leakey Foundation and Kent State University.