Even as news of a staggering 30 per cent increase in India’s endangered tiger population is celebrated the world over, the survey methodology has drawn criticism from ecologist Ullas Karanth, director of the Centre for Wildlife Studies, one of the NGOs involved in the nationwide exercise.
The ‘double sampling’ approach used by the National Tiger Conservation Authority “is not the best currently available methodology for this task,” Mr. Karanth said in a press release. “We do not believe this method can yield sufficiently refined results to accurately measure changes in tiger numbers at landscape or country-wide scales as is being attempted.”
According to the ‘Status of Tigers in India, 2014’ released on Tuesday, tiger numbers rose from 1,706 to 2,226 between 2010 and 2014. The numbers were arrived at by a double sampling approach that brings together data gathered from ground surveys and camera-traps to estimate tiger abundance.
The method of statistical extrapolation is “weak” and based on an old approach developed in 1938, he told The Hindu . “Better alternatives now exist. Rather than a four-year nation-wide exercise, an annual camera-trap survey of certain important habitats would be a more reliable approach.” The final report, expected to be released in March, is likely to be a more robust assessment as it incorporates “Phase IV section 3” protocols based on camera traps, he said.
Habitat lossWhile increasing tiger numbers is “welcome news”, the loss of habitat remains worrying, he said. Tigers originally occupied 380,000 sq. km of existing forests, but are now found in just half that area — in less than 200,000 sq km — according to his estimate. Moreover, only 20 per cent of this area harbours over 90 of India’s tigers.
“All said and done, after India launched Project Tiger in 1973, despite arresting the imminent extinction of the tiger, it has not been able to substantially increase tiger numbers in the last 42 years.”
With cooperation between the Centre and States “there is no reason why we cannot aspire to eventually have 5,000 or even 10,000 wild tigers in India.”