Anthropology, Santa Clara University
Thursday All day, Clinch Concourse
In this study, we examined the vocalizations of Aloutta palliata, the mantled howler monkey. Specifically, we focused on the different types and contexts of vocalizations that occurred. Previous research has suggested that howler vocalizations function as a way of regulating intergroup spacing, a way for males to assess the strength of their opponents, and as a mechanism for males to protect mates. We collected behavioral data using a combination of instantaneous sampling and all occurrence sampling during a two-month period at Estación Biológica La Suerte in Costa Rica during summer 2012. The data presented consists of 170 hours of behavioral data and 2,919 instances of individual vocalizations. A majority of the observed vocalizations (49.5%) occurred in response to the vocalizations of a distant troop. While males completed a majority (88.9%) of these observed vocalizations, all troop members (males, females, and juveniles) were most vocal during foraging and feeding bouts, which constituted 10.69% (320 instances) of total vocalization data. The results presented in this study suggest that mantled howling monkeys vocalizations function in several differing contexts including inter-troop and within group communication.