Action: Install mechanical barriers to deter primates (e.g. fences, ditches)
Key messagesRead our guidance on Key messages before continuing
- We found no evidence for the effects of installing mechanical barriers to prevent primates from entering agricultural areas and raiding crops on primate populations.
'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.
Fencing is the most often used mechanical barrier to keep animals out of agricultural lands. However, fence design and materials can be very expensive and must constantly be maintained. In addition, primates quickly learn how to by-pass electric fences. Furthermore, the area on either side of the fence has to be kept clear of tall vegetation to prevent the animals using overhanging branches to move across the fence. This suggests that such fencing might be more effective for restraining larger, less agile animals such as great apes, than for baboons Papio spp. and guenons Cercopithecus spp. that are able to jump considerable distances. Walls and ditches, on the other hand are considered largely ineffective because of most primate species’ agility and climbing skills (Strum 1994). Canals could be useful barriers, but they have to be deep and wide enough to deter primates from crossing. However, deep, wide canals can create a drowning risk for primates and for humans, as well as pose disease risks if water becomes stagnant, and could become ineffective if problems develop with maintaining water levels. Canals and their banks must be kept devoid of items that primates might use as tools to get across (Hockings & Humle 2009).
Hockings K. & Humle T. (2009) Best Practice Guidelines for the Prevention and Mitigation of Conflict Between Humans and Great Apes. Report by the IUCN/SSC Primate Specialist Group (PSG).
Strum S.C. (1994) Prospects for management of primate pests. Revue d'Ecologie (Terre et Vie), 49, 295–306.