Field Research in Peru:

Ecological Risk Aversion in Cebus albifrons and Saimiri boliviensis in Amazonian Peru

Cocha Cashu Biological Station, Manu National Park, Peru

Janson and van Schaik (1993) suggest that primate juveniles might grow slowly and reach reproductive maturity at a late age in order to reduce the risk of starvation due to high levels of feeding competition in the spatial center of the group where they stay to avoid high predation risk. I conducted preliminary research at Cocha Cashu Biological Station in Peru in order to investigate differences in behavioral and ecological strategies of juveniles and adults in Cebus albifrons and Saimiri boliviensis. The data I collected during the two-month period indicate that juveniles may not respond behaviorally to ecological risks of starvation and predation as suggested above.

It was expected that juveniles would avoid high-risk areas and remain closer to nearest neighbors than would adults. However, the spatial position of juveniles did not differ significantly from that of adults in either species. Similarly, the amount of time spent feeding, foraging and engaging in vigilant behaviors did not differ significantly between age classes. The behaviors exhibited by the juvenile primates in this study are inconsistent with Janson and van Schaik's (1993) ecological risk aversion hypothesis. Although juveniles did seem to respond to the risk of starvation by foraging far from neighbors in likely high-risk areas near food resources, juveniles did not respond as expected to the risk of predation. This suggests that future research on variation in predation risk in space and time may be necessary in order to more fully understand risk aversion.

For more information on Cocha Cashu Biological Station click here.

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