Ecological Relations and Niche Separation between Sympatric Terrestrial Primates in Ethiopia

Abstract

Theropithecus gelada, Papio anubis and Cercopithecus aethiops are commonly sympatric in Ethiopia. It is suggested that niche separation would be more marked among terrestrial open country species than among forest primates. The ecological relationships between these three species in an Ethiopian valley where they coexist are analysed. Quantitative data are presented on density and biomass, size of home ranges and day ranges, activity patterns, use of habitat, diet and feeding patterns and on interspecific interactions. These are compared across the species to determine to what extent ecological competition could occur and in what ways it is reduced. The data are discussed with reference to studies of forest primate communities where niche overlap has commonly been reported.

What Insights Can Baboon Feeding Ecology Provide for Early Hominin Niche Differentiation?

“…Whiten et al (1991) reported that leaves comprise 8-53% of baboon diets; fruits, 3-74%, and USOs, 8-53%. Grasses may contribute anywhere between 0 and 40% to bulk intake (DeVore and Hall 1965;Dunbar and Dunbar 1974). In Laikipia, Kenya, baboons incorporate as much foliage into their diets as folivorous colobines do (Barton et al 1993), and in 1 instance, a baboon troop fed almost exclusively on animal matter (Strum 1975).…”

“…In field studies, Altman (1998), Barton et al (1993), Byrne et al (1993), DeVore and Hall (1965), Dunbar and Dunbar (1974), Norton et al (1987), Whiten et al (1991), and others revealed that baboon diets, excluding the primarily stenotopic graminivore Theropithecus gelada, vary in extreme ways. Stable isotope ecology is one tool that enables researchers to characterize and to quantify at least some aspects of diet in these and other generalist feeders in easily understandable terms.…”

Crop-raiding Baboons (Papio anubis) and Defensive Farmers: A West African perspective

“…By incorporating feeding on crops into their foraging strategies baboons have somewhat transformed their activity budgets (Forthman-Quick, 1986). Social organisation may also be affected by foraging on crops (Dunbar & Dunbar, 1974;Maples et al, 1976;Strum, 1994).…”

Polyspecific Associations of Cercocebus albigena: Geographic Variation and Ecological Correlates

“…Primate polyspecific associations share some characteristics of mixed-species fish schools or bird flocks [Brosset, 1969;Krebs, 1973;Morse, 1969;Moynihan, 1962], although, as described by some authors, they some times differ from these in their higher frequency of nonaggressive interspecific social interactions [Dunbar and Dunbar, 1974;Gartlan and Struhsaker, 1972;Klein and Klein, 1973;Struhsaker, 1975] and perhaps in their stability [Bern stein, 1967;Cashner, 1972;Gautier-Hion and Gautier, 1974], They certainly share with mixed-species flocks a variety of hypothesized evolutionary explana-tions, few of them testable with existing information. In this paper, I (a) present data describing the characteristics of associations between gray-cheeked mangabeys, Cercocebus albigem, and members of other primate species; (b) document geographic variation in the frequency with which mangabeys are found in mixedspecies associations, and (c) assess the importance of various selective factors which have been suggested to favor polyspecific association by examining temporal variation in mangabeys' association tendencies and its correlation with ecological variables.…”