Why did the elephant cross the road? The complex response of wild elephants to a major road in Peninsular Malaysia

Abstract

Roads cause negative impacts on wildlife by directly and indirectly facilitating habitat destruction and wildlife mortality. We used GPS telemetry to study the movements of 17 wild Asian elephants (Elephas maximus) and a mechanistic modelling framework to analyse elephant response to a road bisecting their habitat in Belum-Temengor, northern Peninsular Malaysia. Our objectives were to (1) describe patterns of road crossing, (2) quantify road effects on movement patterns and habitat preference, and (3) quantify individual variation in elephant responses to the road. Elephants crossed the road on average 3.9±0.6 times a month, mostly (81% of times) at night, and crossing was not evenly distributed in space. The road caused a strong and consistent barrier effect for elephants, reducing permeability an average of 79.5%. Elephants, however, were attracted to the proximity to the road, where secondary forest and open habitats are more abundant and contain more food resources for elephants. Although the road acts as a strong barrier to movement (a direct effect), local changes to vegetation communities near roads attract elephants (an indirect effect). Given that risk of mortality (from poaching and vehicle collisions) increases near roads, roads may, therefore, create attractive sinks for elephants. To mitigate the impact of this road we recommend avoiding further road expansion, reducing and enforcing speed limits, limiting traffic volume at night, managing habitat near the road and, importantly, enhancing patrolling and other anti-poaching efforts. Our results are relevant for landscapes throughout Asia and Africa, where existing or planned roads fragment elephant habitats.