Behaviour 2019
Capuchin monkeys (Sapajus spp) interactions with other primates
Tiago Falótico1,2, Olivia Mendonça-Furtado2,3,4, Mariana D Fogaça2,4,5, Marcos Tokuda4,6, Eduardo B Ottoni4, Michele P Verderane2,4. 1School of Arts, Sciences and Humanities - University of São Paulo, São Paulo, SP, Brazil; 2Neotropical Primates Research Group, São Paulo, SP, Brazil; 3National Institute for the Atlantic Forest, Santa Teresa, ES, Brazil; 4Institute of Psychology - University of São Paulo, São Paulo, SP, Brazil; 5University of Veterinary Medicine Vienna, , , Austria; 6Quinzinho de Barros Municipal Zoological Park, Sorocaba, SP, Brazil

Examining interactions among sympatric primate species can provide interesting information about competition, cooperation, avoidance between those species. Capuchin monkeys are medium-sized primates that can encounter both larger and smaller primates in their varied habitats. Gracile capuchins (Cebus) are reported to present different types of interactions with other primates. Interactions with howler monkeys frequently include physical aggression, while interactions with spider monkeys are mostly threats and chases. Moreover, interaction types are not consistent across populations. Among robust capuchins (Sapajus spp.), however, no reports have been published. Here we describe and classify encounters of Sapajus libidinosus and S. nigritus with Alouatta caraya, A. guariba, Brachyteles arachnoides, and Callithrix jacchus in three sites in the environments of Cerrado, Caatinga (savannah-like), and Atlantic forest, and compare the interaction patterns among sites and different group sizes. Our results of 8421h of total contact with the capuchin groups show that, indeed, capuchins in sites with larger groups presented aggressive interactions with higher frequency. However, the other species’ body size also seems important as smaller primates apparently avoided capuchins, and interactions with the larger muriquis were mostly neutral for the capuchin. Capuchins showed neutral or aggressive behaviors toward howler monkeys, with differences between the rainforest and savannah groups. We found that robust capuchins can present aggressive interactions even to primates larger than themselves and that aggressive behavior was the most common response in populations living in larger groups and drier environments.