Making sense of spoors

The study was done based on indirect sign surveys using dhole scats and spoors (animal signs like pugmarks and movement signs). While 267 dhole signs were observed in the 2007 survey in selected grids across dhole habitat in the Ghats, the number dropped to 251 in the 2015 survey.

Dholes in the Western Ghats form a ‘metapopulation’ – a group of populations of the same species separated in space. The dhole metapopulation in the Western Ghats of Karnataka is constituted by smaller subpopulations found in Sharavati, Kudremukh, Nagarhole, MM Hills and so on.

The current study inspected movement between the subpopulations and examined local extinctions. Colonisation, as per the study, is a location that did not have dholes in 2007 but has been occupied by dholes in 2015; local extinction implies a location that had dholes in 2007, but no longer had any as of 2015. The study concluded that while the colonisation rate of the dhole population was higher than the extinction rate, taken together and considering the entire landscape, the total area where dholes went locally extinct was greater than the areas where they colonised.

The researchers discovered that colonisation took place mostly in locations within and around protected areas in a clustered, restricted manner and thus concluded that buffer zones around the protected areas play an important role in revival of the dhole population.

“While the interiors of protected areas might have stable forest cover and prey densities, the locations adjoining protected areas require management intervention. These locations are sensitive to colonisation of dhole population and thus should be safeguarded,” said Srivathsa.

Increased protection in reserves in the Western Ghats has enabled population recovery of tigers and leopards but, according to the study, the dhole population has not benefited.

“Tigers and leopards are more resilient than dholes. Leopards survive and thrive in a wide range of habitats. Tigers do need forest cover but they are also able to disperse long distances through mixed landscapes with forests and human-use areas,” said Srivathsa.

“Dholes are perhaps a lot more sensitive to forest cover and therefore require more nuanced approaches for population recovery. Competition and disease threat from stray/feral [domestic] dogs are very likely compounding the issue but we do not know enough about these dynamics yet,” he added.

The dhole is on the International Union for Conservation of Nature (IUCN) Red List of Endangered Species and is protected under Schedule II of the Wildlife Protection Act, 1972 in India.

Globally, dholes have disappeared from approximately 82 percent of their former range. The Western Ghats perhaps supports the largest dhole population in the world and is therefore a critical conservation landscape for the species. Understanding changes in their distribution is important for prioritising and implementing conservation strategies, write the authors.