How can we justify claims that the decline in tiger population has been reversed when various threats to the animal still persist?
Renowned wildlife biologist and tiger expert Ullas Karanth expressed serious reservations about the methodology adopted in the national tiger population estimation exercise. The results were released in Delhi on Monday, as per which the number of tigers across the country had increased from 1411 in 2006, to 1706.
He called for an end to the government monopoly on tiger monitoring, and suggested that outside expertise and resources be harnessed so as to ensure greater reliability, transparency and credibility in monitoring the fate of the national animal.
Responding to the national tiger estimation figures, Dr. Karanth, Director, Centre for Wildlife Studies, said that it was difficult to justify claims that the decline of the tiger population had been reversed when the various threats faced by the animal had not diminished in the last four years. “The full process of how these tiger numbers are generated for individual tiger populations and landscapes has not been made public in a scientifically acceptable manner. Only one scientific paper, which explains only a part of this protocol, has been published in 2011, based on data from the last round of estimation in 2007,” said Dr. Karanth. “I see serious deficiencies in the methodology which has been published.”
In a release, he said the monitoring of tracks by forest guards was not a substitute for more reliable methods of monitoring — using camera traps or DNA sampling — as had already been proven earlier in cases where tigers had vanished despite guards having done similar patrol-based monitoring. “To me the most serious flaw in the present government effort is the basic futility of trying to generate all-India-level tiger counts once in four years, even while ignoring the critical task of intensively monitoring key source populations year after year,” said Dr. Karanth.
Camera trap methods
He said the time had now come to switch from these four-yearly national estimation exercises and focus on intensive camera trap or DNA monitoring of tiger source populations so that one could track the fate of individual tigers, and estimate survival and recruitment rates to gauge how each of these populations was faring.
Citing works done by the Centre for Wildlife Studies, which has monitored tigers rigorously in Karnataka over an area that holds about 15% of the country's tigers, Dr. Karanth said an area of about 3,000 sq. km was camera-trapped every year and more than 100 tigers photographed out of a population of about 250 tigers. “On the basis of these data, we believe that the tiger population in Karnataka is holding out, and even increasing in some areas like Bhadra and Kudremukh thanks to the good work by government and NGOs. We believe that similar intensive monitoring of all key source populations can be easily done to generate similarly useful results across the country. This would not cost more than what the present ‘once-in-four-year' national estimation costs,” he said.
Dr. Karanth cautioned that if there was no shift to such focused, intensive monitoring approaches, the country was at serious risk of losing more and more key populations even as it celebrated supposed ‘increases'. He drew attention to the fact that many reserves had lost most of their tigers despite these national counts in the past decades.