Audience effects and food-associated calls in tufted capuchin monkeys (Cebus apella)

DI BITETTI, M. S.; BALDOVINO, M. C.

Florianópolis

Conferencia; XXVIII International Ethological Conference; 2003

Several species of birds and primates produce food-associated calls upon finding or consuming food. Tufted capuchin monkeys (Cebus apella) produce two food-associated vocalizations which are functionally referential. By experimentally placing new food sources - platforms hanging from tree branches and containing half pieces of banana - we explored the factors that affect the production of food-associated calls in a wild group of tufted capuchins. Finders of these platforms called in 81% of the discoveries when the platform contained fruit (N = 57) but in 0% of cases when the platform was empty (N = 5). Males and females of all ages and dominance ranks gave food-associated calls when discovering a platform with fruit. There was an audience effect on the latency to give food-associated calls: the time elapsed until the finder gave the first call decreased with the presence of nearby individuals and increased with the distance from other individuals to the platform. The latency to call was longer for subordinate females than for the more dominant males. These results are consistent with the hypothesis that capuchins use these vocalizations deceptively by withholding information about the presence of food. By increasing the latency to call, finders can obtain a larger amount of food and thus reduce the costs associated with calling. Food-calling behavior may be maintained through punishment-enforced cooperation.