Asian elephant movements between natural and human-dominated landscapes mirror patterns of crop damage in Sri Lanka

Abstract

Wildlife movements within a landscape are influenced by environmental factors such as food availability and, as human-modified landscapes continue to expand, the risks associated with encountering people. For Asian elephants Elephas maximus, human-dominated landscapes can be a risky but also rewarding habitat. When elephants share space with people, negative human-elephant interactions are common, sometimes resulting in injuries or deaths of both people and elephants. We monitored elephant movements in and out of a forest reserve in central Sri Lanka to test four predictions regarding elephant behaviour: (1) visits to agricultural areas occur at times of the year when crops are plentiful, (2) elephants exploit these areas by night to avoid interactions with people, (3) increased nocturnal illumination reduces use of agricultural areas, and (4) males make greater use of anthropogenic food sources than family groups. Analysis of camera-trap data confirmed that elephants visited human-dominated areas mostly at night. The frequency of such incursions was not influenced by moon phase for males, but there was a weak effect of moon phase for family groups. Males moved more frequently into human-dominated landscapes than family groups, and their movements showed a distinct seasonal pattern, peaking at times of rice and fruit harvest. Our findings suggest that elephants primarily venture into human-dominated areas to consume crops. Encouraging farmers in areas frequented by elephants to adapt land-use practices (e.g. guarding crops, fencing villages, planting orange/citrus fences) and establish early warning systems could help limit the damage caused by elephants.