New genetic tool pinpoints an estimate dhol population in Kerala
For the first time, scientists have been able to reliably measure the number of the endangered species through its scats.
There are about 50 dhol or Asiatic wild dogs residing in Kerala’s Wayanad Wildlife Sanctuay. This figure is important because although the existence of these wild dogs is known and documented, the scientists were not able to arrive at reliable population estimate of the species. That’s until now. Scientists from Wildlife Conservation Society–India, National Centre for Biological Sciences, Kerala Veterinary and Animal Sciences University, University of Florida, and Stanford University have developed a method wherein for the first time they can accurately estimate how many members of this endangered carnivore exists in the country. The new study was published in the latest international journal Biological Conservation.
By using genetic information and advanced population models, the study found that the 344.44 sq km sanctuary has within its boundaries 12-14 dhols per 100 sq km. To get the genetic data, the scientists conducted field survey to collect fecal droppings or scats of the wild dogs in 2019. With these scats, they were able to get the DNA code of each individual dhole by using a method involving Single Nucleotide Polymorphisms. Further, they used Spatial Capture-Recapture models, which are basically statistical methods to estimate and map the numbers and density of the wild dogs,” said Dr. Arjun Srivathsa, the lead author of the study. Srivathsa is associated with Wildlife Conservation Society–India, and University of Florida.
What’s also interesting is that by knowing the estimated number of dhols, and with the recent national tiger survey indicating a healthy tiger population (11-13 tigers per 100 sq km), the scientists infer that the sanctuary has a good ratio of prey and a high quality habitat in order for two large carnivores to survive in the region. India is home to 23 percent of the carnivore species across the world.
“For species like dhole that do not have individual markings, genetic methods are the only way we can get statistically robust estimates of population size,” NCBS Prof Uma Ramakrishnan, who is one of the co author of the study.
The researchers also recommended that the methods used in the study be made as standard protocol for conducting population survey and conservation monitoring of dholes in other protected areas in the country. “The genetic tool will help researchers understand the species better and plan evidence-based conservation of dholes, Ramakrishnan added.
The other authors of the study included co lead Ryan G. Rodrigues from Wildlife Conservation Society -India, and National Centre for Biological Sciences, Dr Kok Ben Toh and Dr Madan K. Oli of University of Florida, Dr Arun Zachariah from Kerala Veterinary and Animal Sciences University, and Dr Ryan W. Taylor from Stanford University.