Abstract This chapter explores variation in orangutan diets across their range, based on food lists. The authors of the chapter consolidated orangutan food lists from all available long-term field sites (N = 15). They represent both islands, multiple habitat types, varied degrees of degradation, and wild and rehabilitant populations. The chapter assesses the effects of habitat productivity (island, habitat type, habitat degradation) and rehabilitant–wild status on food lists. Findings suggest inverse relationships between habitat productivity and total plant taxa eaten at a site, the intensity at which individual food taxa are used, and the proportion of plant food species from which important food types are eaten. Analyses also explore food lists to suggest medical plant use, cultural influences on food knowledge, and the relationship between orangutan and other great ape diets. Discussion concerns conceptual implications of findings, methodological limitations to using food lists in the study of diet, and conservation applications.

Geographic variation in orangutan diets