Interactions between Bengal tiger (Panthera tigris) and leopard (Panthera pardus): implications for their conservation

Bengal tiger and common leopard belong to endangered species in Nepal and elsewhere. They share their prey species, thus one affects prey availability of the other, which may contribute to decline in numbers of these carnivores. However, data on these interactions are very rare. We studied diet composition of tiger and leopard in Chitwan (Nepal), by analysing remnants of prey in scats of these two species and comparing abundance of prey species in scats with prey abundance recorded along line transects. We found that tiger prefers medium-sized (30–175 kg) prey, while leopard prefers small-sized (5–30 kg) prey, but also often eats medium-sized prey. Domestic animals (especially small ones) are more often eaten by leopard, compared with tiger. Consequently, these two predators compete mainly for medium-sized prey, but leopard relies more on small prey and domestic animals than tiger. We found that prey preferences of tiger and leopard also depend on the degree of habitat disturbance. Predators killed domestic animals in areas where there was a low density of wild prey. The conflict between humans and carnivores is the most important challenge threatening the conservation of carnivores, which depend on the abundance of different-sized prey and little human disturbance. Hence, restoring large populations of prey and reducing the level of human disturbance are the key measures necessary for the effective conservation of tiger and leopard.