India's cats and dogs living in surprising harmony: study

India's tigers, leopards and dholes - the three carnivores seemingly in direct competition with one other - are living side by side with surprisingly little conflict, a new study has found.
Usually, big cats and wild canids live in different locations to avoid each other.
Yet in four relatively small reserves in India's wildlife-rich Western Ghats region, researchers from Wildlife Conservation Society have found that they are co-existing, despite competing for much of the same prey, including sambar deer, chital and pigs.
Using dozens of non-invasive camera traps for sampling entire populations, rather than track a handful of individuals, the research team recorded some 2,500 images of the three predators in action.

The researchers found that in reserves with an abundance of prey, dholes (Asian wild dog), which are active during the day, did not come in much contact with the more nocturnal tigers and leopards.
However, in Bhadra Reserve in Karnataka where prey was scarcer, their active times overlapped, yet dholes still managed to avoid the big cats.

In Nagarhole National Park in Karnataka, teeming with all three carnivores and their prey, leopards actively avoid tigers.
The researchers said that these carnivores have developed smart adaptations to coexist, even while they exploit the same prey base. However, these mechanisms vary depending on density of prey resources and possibly other habitat features.

"Tigers, leopards and dholes are doing a delicate dance in these protected areas, and all are manging to survive," said Ullas Karanth, WCS Director for Science in Asia and lead author of the study.
"We were surprised to see how each species has remarkably different adaptations to prey on different prey sizes, use different habitat types and be active at different times.
"Because of small and isolated nature of these high prey densities in these reserves, such adaptations are helpful for conservationists trying to save all three," Karanth said.
Both tigers and dholes are classified as Endangered by International Union for Conservation of Nature (IUCN); leopards are considered Vulnerable.

Understanding these separate yet overlapping species' needs is critical to managing predators and prey in small reserves, which is increasingly the scenario of the future.
The researchers said that by managing populations of flagship predators, like tigers, carefully overall biodiversity can also be conserved.
The study was published in the journal Proceedings of the Royal Society of London B: Biological Sciences.