135 S. Radhakrishna et al. (eds.), The Macaque Connection: Cooperation and Conflict between Humans and Macaques, Developments in Primatology: Progress and Prospects 43, DOI 10.1007/978-1-4614-3967-7_9, © Springer Science+Business Media, LLC 2013 9.1 Introduction In spite of Sri Lanka’s relatively small size (64,740 km 2 ), the island supports a high level of biodiversity and endemism (Gunathilleke and Gunathilleke 1983; Erdelen 1988). Part of the reason for this high degree of biodiversity is the variety of habi- tats found between sea level and the highest peak, 2,524 m asl in the central high- lands. The habitat types include mangrove forest, grassland, semiarid thorn forest and shrub land, tropical evergreen rain forests, dry mix evergreen, intermediate moist evergreen, highland evergreen, and temperate forests (Erdelen 1988). There are five primate species in Sri Lanka, the toque macaque ( Macaca sinica), the gray-handed crested langur ( Semnopithecus priam thersites), the purple-faced leaf langur ( Trachypithecus vetulus), and the two nocturnal lorises ( L. tardigradus and L. lydekkerianus). With the exception of S. priam and L. lydekkerianus, all are endemic and classified as endangered or critically endangered (Dela 2007; Rudran 2007; Nahallage and Huffman 2008). Sri Lanka is primarily an agricultural country, and over the last few decades, due to agricultural, irrigational, and industrial projects and an increase in the human population and urban expansion, natural forested areas have declined rapidly (Erdelen 1988; Wickramagamage 1998). Owing to fragmentation of forests in the wet and dry zones, primates are increasingly frequenting farms and agricultural plots in search of alternative food resources (Nahallage and Huffman 2008). This is the main cause for primate–human conflict today. C.A.D. Nahallage (*) Department of Sociology and Anthropology, University of Sri Jayewardenepura, Gangodawila, Nugegoda, Colombo, Sri Lanka e-mail: charmalie2@hotmail.com M.A. Huffman Department of Social Systems Evolution, Primate Research Institute, Kyoto University, 41-2 Kanrin, Inuyama, Aichi 484-8506, Japan Chapter 9 Macaque–Human Interactions in Past and Present-Day Sri Lanka Charmalie A.D. Nahallage and Michael A. Huffman