Abstract # 4326 Poster # 47:

Scheduled for Thursday, June 21, 2012 07:00 PM-09:00 PM: Session 9 (Gardenia) Poster Presentation


SUBSTRATE TAPPING AND DESTRUCTIVE INSECT FORAGING EFFICIENCY ACROSS ECOLOGICAL, SOCIAL, AND DEMOGRAPHIC VARIABLES AMONG WILD WHITE-FACED CAPUCHIN MONKEYS (CEBUS CAPUCINUS)

C. Dillis1 and S. Perry2
1University of California-Davis, One Shields Avenue, Davis, CA 95616, USA, 2University of California-Los Angeles
line
     Destructive foraging generates a substantial proportion of the insect diet of white-faced capuchins (Cebus capucinus) at Reserva Biológica Lomas Barbudal. Although there are rare observations of foraging for larvae embedded deep in living tree tissue, destructive insect foraging occurs almost exclusively in small, dead branches (~1-2cm in diameter). This source of prey is more evenly distributed in the environment, with comparatively less time and effort devoted to any single substrate, thus minimizing the importance of search efficiency relative to handling efficiency. While foraging, individuals appear to rely on visual and tactile cues to detect prey, often implementing a technique of substrate tapping. Using data from 25 focal individuals, from seven social groups, over eight continuous years of observation, we found substantial covariation across ages and between sexes in the use of this tapping behavior and handling efficiency. Both steadily increased with age, however females used this tapping technique more than males and demonstrated greater handling efficiency. We also accounted for seasonal variation in stick foraging, differences between groups, and sociality of individuals, in constructing a general linear multilevel mixed model to identify contributions of all variables to destructive insect foraging efficiency. This efficiency has large implications, considering this source of insects represents nearly half (42%±16) the insect diet, which is itself the single most important source of dietary protein.