Lion census method outdated: experts
Deaths due to a virus were not reported, they say
An outdated methodology and the true mortality from a virus affecting India’s lions dent the credibility of the Gujarat government’s claims on its lion population. On Wednesday, Prime Minister Narendra Modi and Union Environment Minister Prakash Javadekar tweeted results of the 2020 Asiatic Lion Census that put the number of lions at 674, a 28% rise from 2015.
A wildlife biologist who closely works with the Union Environment Ministry on wildlife surveys said that the canine distemper virus (CDV) that killed at least 36 lions in Gir, Gujarat in 2018 had not ebbed. This was in spite of the government inoculating lions with an imported vaccine. “There have been more deaths from the virus since January but no data about these have been shared,” the biologist said.
Yadvendradev Jhala, senior scientist at the Wildlife Institute of India (WII), an autonomous organisation of the Union Environment Ministry, said the Gujarat government uses a 100-yearold method to count lions that would not “stand the scrutiny of contemporary science”. This approach, called the Direct Beat Verification or Block Count method, involves officials from the State wildlife department laying stake at watering holes across the animals’ territorial range.
This year, from June 5-6, department officials monitored the numbers of the lions. In normal years, alongside these forest officials, there would be independent experts and observers from non-governmental organisations. This year, the process involved 1,400 personnel. Normally, about 2,000 persons would be involved and the monitoring would be done over two days. The reduction in number of people involved was due to travel restrictions imposed for the pandemic.
Dr. Jhala said that newer methods such as camera trapping and identifying lions based on permanent marks on their body, and statistical estimates based on the animals’ predatory patterns and numbers of their prey base — all of which were used to count tigers — were more scientifically precise. In a research paper published in in February, he and colleagues, based on a survey in Gir, identified 67 individual lions from 368 sightings. “Using photographs and other markers, we can reliably identify individuals but we have been never allowed to do a census. I have been trying for 15 years. With the current methods and the fact that lions can range as much as 700 sq. km., you can both grossly under count or over count,” he said.
An official from the Union Environment Ministry’s wildlife division said, “Camera traps are not yet suitable for lions as they don’t have clearly discernible permanent physical features, unlike in tigers, which have unique stripes. There are lots of ideas but going ahead, we will consider newer methods that are practical. The CDV was an issue in 2018 but this year, we haven’t yet got any report of such deaths,” the official said.
H.S. Singh, a member of India’s National Board for Wildlife and an expert on Gir lions estimates 26 lions to have succumbed to CDV this year. “The virus is endemic in livestock and periodically infects lions so only largescale vaccination of livestock can help. However, I don’t think it significantly decreases the population. That 60% of the lions are outside the protected area and increasing is a more serious issue.”
Pride of place: Lions resting in the Gir sanctuary