Abstract # 13326 Poster # 167:

Scheduled for Friday, August 23, 2019 06:00 PM-08:00 PM: (Alumni Lounge) Poster Presentation


L. R. LaBarge1,2, S. W. Margulis4,5, C. M. Berman1,4 and R. A. Hill2,3,6
1Program in Evolution, Ecology and Behavior, The State University of New York, University at Buffalo, Amherst, NY 14228, USA, 2The Primate and Predator Project, Lajuma Research Centre, Makhado, South Africa, 3Department of Anthropology, Durham University, Dawson Building, South Road, Durham DH1 3LE, UK, 4Department of Anthropology, The State University of New York, University at Buffalo, 5Department of Animal Behavior, Ecology and Conservation, Canisius College, Buffalo, NY, USA, 6Department of Zoology, University of Venda, Private bag X5050, Thohoyandou 0950, South Africa

Spatial cohesion in groups of wild primates is predicted to be dependent on resources as well as potential risks. In this study we investigate potential reactionary changes in samango monkey (Cercopithecus albogularis schwarzi) group cohesion in response to local availability of rare fruiting trees, inter-group competition, and/or predation risk. We use data from three years of observation on two groups (N=80 and N=45) and vegetation survey data collected in the Soutpansberg Mountains, South Africa. This dataset includes 2120 behavioral samples collected prior to, during, and in the hour following 139 eagle encounters and 347 inter-group encounters. We compared support for several a priori developed models using an I-T approach with AICc and GLMMs where our response was a count of the number of conspecifics each individual had within 5 meters. Results from our best models ((ΔAICc<7) suggest that inter-group encounter events are associated with increased cohesion (top model: β = 0.343, Z = 7.523, 95% CI = ± 0.11). We also found that the larger group tended to be less cohesive than the smaller (β = -0.295, Z = -6.72, 95% CI = ± 0.086). Our preliminary results suggest that inter-group competition and group size are important for reactionary changes in spatial cohesion for samangos in this environment but do not suggest that predation or feeding on fruiting trees are similarly important.