Foraging behaviour of three primate species in a Costa Rican coastal lowland tropical wet forest

Primates are predominantly distributed across tropical regions, many of which are threatened by deforestation. Removal of mature trees can harm primate populations by reducing available food resources. Understanding the dietary requirements of primates at local levels can help identify key habitats to conserve, and protect plant species on which primates rely. Little is known about local diets of Alouatta palliata (mantled howler monkey), Ateles geoffroyi (black-handed spider monkey), and Cebus capucinus (white-faced capuchin) in Costa Rica's lowland tropical wet forests. Because diet and activity levels are closely connected, studies examining one provide insight into the other. We used group scan sample methods to record activity and diet, identifying all plant species on which the primates fed. We identified nine families of plants eaten by Ateles geoffroyi, four families eaten by Alouatta palliata, and two families eaten by Cebus capucinus. Activity budgets demonstrated that Alouatta palliata was the least active species and Cebus capucinus the most active. We also found differences in the type of plant parts consumed by the three primate species; Alouatta palliata and Ateles geoffroyi fed mostly on fruit and new leaves, whereas Cebus capucinus fed on fruit and insects. The nine families of plants identified in this study are potentially important for all three primate species locally, and warrant conservation