Behavioral Indicators of Stress in Female Chacma Baboons of the Cape Peninsula, South Africa
Jacqui Stephenson (B.Sc. honours University of Cape Town, 2007)
Jacqui's project focused on self-directed behaviors (SDBs) among female chacma baboons of the Cape Peninsula. Self-directed behaviors have been shown to be associated with stress or anxiety in macaques and baboons, and, in the absence of hormonal data, we thus used them as a proxy for stress levels. Jacqui found rates of SDBs in her study troop, the Cape Point troop, to be significantly higher than those in olive baboons (Castles et al. 1999), which could indicate greater stress levels or higher ectoparasite loads. Jacqui did not find SDB rates or self-grooming bout duration to be related to female dominance rank, but rates of SDBs were significantly higher in pregnant and lactating females than in cycling females. Finally, self-grooming bout duration was significantly shorter when the troop was being herded by baboon monitors compared to when baboon monitors were absent. This study is suggestive of higher stress levels among females most at risk for infanticide and is also indicative of an effect of baboon monitors on baboon behavior.
Stephenson, J., Swedell, L., O’Riain, M.J. (2008) Behavioral indicators of stress in female chacma baboons: Social structure, female reproductive state, and human impact. American Journal of Physical Anthropology Supplement 46: 200 (presentation at 2008 annual meeting of the American Association of Physical Anthropologists).