Govt challenges claims on flawed methodology in tiger census

New Delhi: The government today challenged claims by sections of wildlife experts that it had used a flawed methodology for its latest tiger census and instead asserted that their study was a "theoretical iteration" on old data whose precision is "questionable".

The National Tiger Conservation Authority (NTCA), a statutory body under the Environment Ministry today sent a clarification regarding the recent study led by Oxford University which found the Ministry's methodology flawed and said that biologists themselves have used imprecise, low-quality data to question the tiger estimation methodology.

The NTCA, which had in January estimated that India had 2,226 tigers, said the issues that a team of Indian wildlife scientists had raised has "no relevance to the 2014 tiger population and status estimation".

"Recently there have been some news reports in a section of media, based on the published study by Arjun Gopalaswamy and Ullas Karanth. The content of these published articles have no relevance in the context of 2014 tiger population and status estimation," NTCA said in a clarification today.

A team of scientists from University of Oxford, Indian Statistical Institute and Wildlife Conservation Society led by tiger conservation expert Ullas Karanth recently claimed to have exposed inherent shortcomings in the 'index-calibration' method which meant it could produce inaccurate results.

Flaws in a method commonly used in censuses of tigers and other rare wildlife put the accuracy of such surveys in doubt, the researchers had said.

"There is a remedy for poor data analysis but there is no remedy for poorly collected data; any insights that emerge from these is also likely to be seriously flawed and may mislead even well meaning scientists. We believe such is the case with the current paper by Karanth and colleagues.

"The current study is basically a theoretical iteration on old data whose precision is questionable as it is based on artificial replications done by software rather than extensive search efforts in the field," NTCA said.

NTCA said the study published by Gopalaswamy is based on data of 2005 and 2011 and has deliberately ignored methods used in recent estimation which are currently most advanced and robust spatial models and address all concerns raised in recent publication in 'Methods in Ecology and Evolution'.