Smith, Mick; Desdames, Chloe (University of Utah)
Faculty Advisor: Seaboch, Melissa (University of Utah, Anthropology)
Census and sampling work are important because they provide critical information on population size, distribution, and habitat preference — all important factors in conservation. La Selva Biological station is located on the north eastern side of Costa Rica and is a protected biological reserve. It is home to three species of primates including Alouatta palliata, commonly known as the mantled howler monkey. It is comprised of primary forest that has been undisturbed by human forces and secondary forest that is regenerating from past disturbances, such as deforestation. Past research conducted on howler monkeys shows they prefer primary forest over secondary because primary forests have higher species richness and a wider range of trees which provides food for howler monkey's selective diet. I predict that the majority of A. palliata in Costa Rica will be located in primary forest because it offers more resources. I censused 11 established trails at La Selva (two trails in primary forest, seven trails in secondary forest, and two trails crossing both forest types). For each howler monkey encountered, I recorded the location, forest type, and group size. I identified four different groups of A. palliata with group size ranging between 6-10 individuals. One group was located in primary forest and three groups in secondary forest; thus, my hypothesis that A. palliata would prefer primary forests was not supported. Anecdotally, A. palliata were observed more frequently around rivers or streams. This could indicate that rather than being concerned with primary versus secondary forest, they prefer riparian habitats found along the banks of rivers or other actively moving sources of water. A study conducted by Stoner found howler monkeys in riparian habits supporting this hypothesis. This type of research continues to provide critical information for understanding primate's habitats which helps with conservation of species.