Nonlethal management of baboons on the urban edge of a large metropole.

Abstract

The transformation of natural land for agricultural and urban use has displaced baboons from large parts of their historical distribution. Abundant resources within transformed areas, however, continue to attract baboons back into these human-dominated areas resulting in chronic levels of conflict throughout much of Africa. In the city of Cape Town, chacma baboons (Papio ursinus) have been raiding human-derived foods for over 200 years. In the last 20 years, the management of this conflict has shifted from predominantly lethal to nonlethal methods. In this study, we assess the success of field rangers to deter baboons from urban areas and investigate whether such management affects the diet and activity patterns of baboons. We opportunistically sampled baboon behavior and movement when field rangers were temporarily absent from managed troops in 2008. We also compared the intensity of baboon management by comparing one troop on days when the field rangers aggressively herded the troop away from the urban edge versus passively monitored them in 2004/2005. Our results reveal that when field rangers were absent, the two troops spent 70% and 80% of their time within the urban edge compared to 3% and 19% when they were present. Both troops also consumed more human-derived foods when field rangers were absent. There was no significant change in the activity budget or daily distance traveled for either troop with and without field rangers. The intensity of herding did have an impact on baboon activity and high levels of herding significantly reduced time spent feeding and increased time spent traveling, socializing, and resting. Habitat use and dietary composition did not differ between high- and low-herding days. Our results suggest that field rangers are a successful nonlethal method for reducing spatial overlap between baboons and urban areas but that intensive, unsystematic herding of the troop does have measurable impacts on behavior and should be prevented.