The value of disturbance-tolerant cercopithecine monkeys as seed dispersers in degraded habitats

Habitat disturbance has caused a global decline in populations of frugivores, with critical consequences for seed dispersal. Large-seeded plants are especially threatened as they depend on a restricted number of large-bodied dispersers that are vulnerable to extinction and cannot maintain populations in most disturbed habitats. Cercopithecine monkeys are potentially key seed dispersers in disturbed habitats, because of the robustness of some species to disturbance and their ability to disperse large seeds. However, the potential ecological roles of the more disturbance-tolerant species are rarely discussed. This review evaluates the seed dispersal role of cercopithecines in disturbed habitats by investigating their ability to tolerate habitat disturbance, their seed dispersal abilities, and the threats to species survival. Cercopithecines are characterised by ecological flexibility; most species adjust their diet, group size, home range size and, often, feeding methods according to resource availability and habitat structure. Consequently, 79% of species are tolerant of varying degrees of habitat disturbance. Cercopithecines are often inconsistent seed dispersers, but they have the capacity to disperse many seeds, large seeds and to disperse them across large distances. They may be among the most important frugivores in altered environments in Asia and Africa. However, many disturbance-tolerant cercopithecine species are targeted by local people as pests, which poses a major threat to their conservation. In conclusion, the management of all disturbance-tolerant cercopithecine species should be re-evaluated given their importance in the regeneration of degraded Asian and African habitats. (C) 2013 Elsevier Ltd. All rights reserved.