Managing conservation flagship species in competition: Tiger, leopard and dhole in Malaysia

Abstract

Managing populations of large carnivore species that are threatened yet in competition with each other presents a conservation challenge over which species to prioritise. We investigated interspecific competition between the Endangered tiger and two sympatric carnivore species (Near-Threatened leopard and Endangered dhole) in Malaysia. We used a spatially-explicit camera trapping method to sample the three carnivore species in order to assess their: relative abundance; spatial co-occurrence; and, temporal overlap. Our focal landscape consists of two adjacent study areas that have different forest management regimes: 1) Royal Belum State Park (RBSP) which has relatively higher levels of enforcement resulting in high tiger and prey densities, and 2) Temengor Forest Reserve (TFR) which has no enforcement resulting in low tiger and prey densities. Our analyses found interspecific competition in the form of fine-scale spatial avoidance of tiger by leopard in RBSP, but not in TFR. Thus, leopard was less likely to occur in forest patches with greater tiger presence in RBSP. Dhole was not detected in RBSP, and showed no fine-scale spatial avoidance of tiger on TRF. It was unclear if absence of dhole in RBSP was due to the high tiger density, or another factor such as disease. Regardless, our results indicate dhole can persist in human-degraded forest landscapes. Neither leopards nor dholes showed any major temporal avoidance of tigers on either site. Our findings of fine-scale spatial avoidance by leopard towards tiger and possible exclusion of dhole by tiger in areas of high tiger density were similar to that found in other areas of Asia. Our study demonstrates that degraded forest can be important for threatened carnivores. It also provides a reminder that efforts to recover tiger populations, a conservation priority, may require flanking measures to secure meso-predator populations, especially those forced into edge environments where they come into greater contact with people.