Competition, predation, and the evolutionary significance of the cercopithecine cheek pouch: The case of Cercopithecus and Lophocebus

Abstract

Reports of cercopithecine cheek pouch use and functional significance are largely anecdotal, and to date there have been no investigations into its use by species living in closed forest habitats. Here, I report on cheek pouch use in Cercopithecus ascanius and Lophocebus albigena in the Kibale National Park, Uganda, between July-October 1997. Two hypotheses were evaluated: this feature was selected for because of its role in 1) increasing feeding efficiency via a reduction in potential feeding competition, and/or 2) reducing vulnerability to predation. Results indicate that both species were more likely to use their cheek pouches when feeding on contestable foods and, after filling cheek pouches, retreated to more densely vegetated ("safer") positions for processing food. There was no influence of age and sex on L. albigena cheek pouch use. Subadult C. ascanius cheek-pouched less frequently than adults, although there were no differences between adult males and females. There was no relationship between feeding-patch size and number of plant food items cheek-pouched in either species. However, the diameter of breast height (dbh; a measure of patch size) of trees in which C. ascanius used their cheek pouches was significantly larger than the dbh of trees in which they did not. Both species were more likely to use their cheek pouches in the presence of greater numbers of conspecifics. These data provide insight into the relationship(s) among oral anatomy and feeding efficiency, and facilitate understanding into the selection for this important oral feature in stem cercopithecines.

Primate seed dispersers as umbrella species: a case study from Kibale National Park, Uganda, with implications for Afrotropical forest conservation

“…However, results from previous work [Lambert, 1997[Lambert, , 1998[Lambert, , 1999unpub] can be recruited here (Table VIII). Overall, seed handling behaviors of a given fruit species are highly consistent within a frugivore species [Lambert, 1997[Lambert, , 1999[Lambert, , 2005. Squirrels, parrots, and colobines generally are seed predators, although occasionally seeds escape mastication and are defecated or regurgitated intact.…”

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

“…Whole fruits are stored in the cheek pouches, and then returned singly to the oral cavity where pulp is removed and the seed is spat out. They are used by animals mainly to store fruits while continuing to move, which has beneficial consequences for their ability to exploit fruit crops in stressful conditions (Lambert and Whitham, 2001) as well as for seed dispersal (Lambert, 2005). Most species (72%) have large cheek pouches they use frequently, while the six species with small cheek pouches use them infrequently (Murray, 1975;Appendix A).…”

“…Intra-specific feeding competition is among the most important determinants of fruit handling behaviour, and subsequent seed deposition patterns in cercopithecines, because it promotes cheek pouch use, and encourages individuals to move away from the food source to process fruits and deposit seeds (Lambert, 2005;Smith et al, 2008). The intensity of competition between individuals is influenced by habitat quality, resource distribution and troop size, and consequently may change for cercopithecine populations inhabiting disturbed habitats.…”

“…While larger troops have a greater number of competitors (Murray, 1975;Oates, 1987), the impact of troop size on fruit handling is relative to the abundance and distribution of resources. In habitats with patchily distributed, high quality, resources (e.g., forests), competition among individuals can be intense and cheek pouch-use more frequent (Lambert, 2005), particularly in larger food patches because sub-groups are less likely to occur . In smaller food patches, fission of the social unit may occur, which precludes an increase in competition Chapman and Chapman, 2000;Fukuda, 1989).…”

Les mones de Lowe (<i>Cercopithecus campbelli lowei</i>) utilisent une stratégie de fourragement optimale dans la forêt Réserve de l’Université d’Abobo-Adjamé, Côte d’Ivoire

“…Une autre raison écologique pour expliquer ce résultat serait que les cercopithèques ne consomment pas toujours sur place, les items alimentaires récoltés, ce qui est de nature à contribuer à réduire significativement le temps de séjour dans une aire de fourragement. En effet, ils possèdent des bajoues leur permettant de stocker de la nourriture pendant un certain temps (Mc Graw, 1998 ;Lambert, 2005).…”