Floristic heterogeneity between forested sites in Kibale National Park, Uganda: insights into the fine‐scale determinants of density in a large‐bodied frugivorous primate

Abstract

Summary1. Despite a long history of research on the influence of fruit availability on the population density of large-bodied vertebrate frugivores, operational understanding of the factors regulating density in these taxa remains elusive. We propose that fruit resources can be distinguished from one another on the basis of their functional role for the animals in question, and that such a classification system can aid in identifying the most influential determinants of frugivore density. 2. We compared the availability of several resource classes between two sites in Kibale National Park, Uganda separated by only 12 km yet differing threefold in density of chimpanzees (Pan troglodytes). 3. We categorized plant species used for fruit by chimpanzees according to their availability relative to habitat-wide fruit productivity, and by their tendency towards inter-individual fruiting synchrony. We predicted that the site of high chimpanzee density would support a higher density of food plant species tending to produce crops during periods of high habitat-wide productivity [high fruit abundance (HFA foods)] and of those tending to fruit synchronously among individuals during times of low habitat-wide availability (sLFA foods). The first food class should provide chimpanzees with a high nutrient density (and thus promote population growth), whereas the second should provide stable subsistence during lean periods and thus a temporally consistent resource base. 4. Counter to our prediction, only sLFA resources were more abundant at the site of high chimpanzee density than at the site of low density. We suggest that sLFA resources are most important in influencing density of large-bodied frugivores.

Group augmentation, collective action, and territorial boundary patrols by male chimpanzees

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Chimpanzee fauna isotopes provide new interpretations of fossil ape and hominin ecologies

“…Ngogo is 10 km from Kanyawara at 1350 m elevation [21] and remains primary forest, while logging has occurred within Kanyawara. Kanyawara and Ngogo fauna were collected in the 1990s when carcasses were found in the forest.…”

The influence of ecology on chimpanzee (Pan troglodytes) cultural behavior: A case study of five Ugandan chimpanzee communities.

“…The Kanyawara site is composed of mature forest, swamp, grassland, plantation, and secondary forest (Emery Thompson & Wrangham, 2006;Struhsaker, 1997). The Ngogo site is characterized as closest to a lowland forest (Potts, Chapman, & Lwanga, 2009). Budongo Forest is a lowland moist evergreen forest, composed of four main types: a mature Cynometra-dominant forest, a mixed secondary forest, a colonizing forest, and a swamp forest, all present in the Sonso study area (Plumptre & Reynolds, 1994).…”