High Altitude Diets: Implications for the Feeding and Nutritional Ecology of Mountain Gorillas

Abstract

Though the majority of primates live in tropical habitats, several species partially or exclusively range in high altitude regions of Africa, Asia, and Madagascar (Blanco and Rahalinarivo 2010; Iwamoto and Dunbar 1983; Kirkpatrick and Grueter 2010; Mendiratta et al. 2009; Watts 1998; Whiten et al. 1987). The dif ferences among the diets of high and low altitude primates are likely due to characteristics in their environment. It has been generally accepted that plant species diversity and density decreases with increasing altitude (Aiba and Kitayama 1999; Hamilton 1975; Pellissier et al. 2012; Proctor et al. 2007; Rahbek 1995; Sharma et al. 2009; Vázquez and Givnish 1998; Zhuang et al. 2012). The number of species of understory herbs, shrubs, and vines decreased as altitude increased along the altitudinal gradient from Mexican seasonal dry forest to cloud forest (Vázquez and Givnish 1998). African forests at higher altitudes have fewer fruiting trees, fewer large buttressed trees and lianas, and lower fruit availability, compared to lower altitude forests (Hamilton 1975; Proctor et al. 2007; Schmitt et al. 2010). A similar pattern is seen in Asia, where lower altitudes are charac terized by larger numbers of fruiting trees, and higher altitudes are more likely to be composed of herbs and shrubs (Zhuang et al. 2012)