A new study reveals India’s first-ever population estimates of the endangered dhole (or Asiatic wild dog) in Wayanad Wildlife Sanctuary, Kerala
India has the privilege of hosting a wide diversity of wildlife. The country supports 23 per cent of the world’s carnivore species in around 2.3 per cent of the global land area. Unfortunately, some of these species are threatened with extinction, even as their population numbers remain unknown. The Asiatic wild dog or ‘dhole’ is one such endangered large carnivore found in the forests of India. Until now, there were no methods available to reliably estimate dhole populations. In a new study, scientists from Wildlife Conservation Society–India, National Centre for Biological Sciences, Kerala Veterinary and Animal Sciences University, University of Florida (USA), and Stanford University (USA) developed a scientifically robust method to estimate dhole numbers for the first time, using genetic information and advanced population models.
The scientists conducted field surveys across 350 sq km of Wayanad Wildlife Sanctuary (Kerala, India) to collect dhole scats (faecal droppings) in 2019. They extracted DNA from the scats and used a novel approach involving Single Nucleotide Polymorphisms or SNPs to identify unique dhole individuals. Combining this with sophisticated statistical methods called Spatial Capture-Recapture models, the researchers were able to estimate and map dhole numbers and density across the sanctuary.
The study found that Wayanad has 12–14 per 100 sq km, with around 50 individuals estimated within the sanctuary’s administrative boundary. “Ours is the first attempt to estimate dhole populations through targeted surveys designed specifically for this species. The results suggest that Wayanad supports high densities of the dhole. Recent nationwide tiger surveys showed that the sanctuary also has a relatively large tiger population, with 11–13 animals per 100 sq km. The fact that two large carnivores can co-exist in such high densities is indicative of an abundant prey base and high-quality habitat. It is also a testament to how well the sanctuary is managed by the Forest Department,” said Arjun Srivathsa, the lead author of the study.
According to co-author Uma Ramakrishnan, “For species like dholes that do not have individual markings, genetic methods are the only way we can get statistically robust estimates of population size. The cutting-edge genetic tools we developed here to understand more about this endangered species will be critical for evidence-based conservation of dholes.” The authors recommend that the methods developed and demonstrated in the study should be used as a standard protocol for estimating dhole numbers and for conservation monitoring of their populations in other Protected Areas in India and across the species’ distribution range.
The study titled, “The truth about cats and dogs: Next-generation sequencing and spatial capture-recapture models offer opportunities for conservation monitoring of an endangered social canid” was just published in the international journal Biological Conservation. The authors include Dr Arjun Srivathsa (Wildlife Conservation Society–India and the University of Florida, USA), co-lead Ryan G. Rodrigues (Wildlife Conservation Society–India and National Centre for Biological Sciences), Dr Kok Ben Toh (University of Florida, USA), Dr Arun Zachariah (Kerala Veterinary and Animal Sciences University), Dr Ryan W. Taylor (Stanford University, USA), Dr Madan K. Oli (University of Florida, USA) and Prof. Uma Ramakrishnan (National Centre for Biological Sciences).
