How They Count Our Tigers

How dubious science and faulty equipment created a far-fetched feel-good number.

How dubious science and faulty equipment created a far-fetched feel-good number.

1706. Tigers are finally making good news with the second all-India population estimation reporting a 12 per cent rise in their numbers. Environment and Forests minister Jairam Ramesh and his worthy babus looked suitably pleased announcing the new census figures, declared 28 March at a quadrennial event, perhaps best described as the Tiger Olympics.

A figure-happy media lapped up the good news: why even discounting the Sunderbans figures (70) not available in 2008, tiger numbers have gone up from 1411 to 1636.

If only the estimate was credible.

When the government (read: Project Tiger and Wildlife Institute of India) junked the traditional, human error-prone pugmark census method, the promise was of robust science. Indeed, pugmark identification is a specialised art that often degenerates into mumbo-jumbo. But what we have in its place is equally dubious.

Back in 2006, an international team of experts led by John Seidensticker of the department of conservation biology at Smithsonian’s National Zoological Park in Washington, DC was invited for a peer review. In its report, the team observed that the new estimation method, too, relied on the “integrity of the primary data collectors, data compilers and their supervisors.”

The peer review warned that the genetic methods proposed in the census were not “fully developed for this application”. It said that there were not enough GPS (global positioning system) sets to map out the terrain as per the methodology, and questioned the feasibility of the exercise given that more than 40,000 forest units would have to be sampled.

The first all-India estimate was due in July 2006. It was delayed by nearly two years. You could call that teething trouble. But the second all-India census experience showed that the establishment had still not got its act together.

Seidensticker’s peer review cautioned that “there is also no detailed write-up of the technical analysis, explicitly identifying the analytical techniques to be used in each phase of the framework.’’ In 2008, the first all-India estimation report accepted that “these population estimates have high variances, but since these estimates are not to be used for monitoring trends… they should suffice the need for converting a relevant ecological index to a more comprehensible concept of numbers.”

High variances mean unreliability. In simple terms, they mean different results at different estimation attempts. Nevertheless, those unreliable estimates were extrapolated to larger areas to arrive at all-India tiger numbers. To quote former WII scientist K Yoganand, this approach “was fundamentally flawed and rendered the whole exercise of estimating tiger numbers in India futile.”

Moreover, the official count only referred to standard errors (SE) of estimated densities and population sizes while offering a range of 1,165-1,657 tigers. Yoganand pointed out that the authors never used the appropriate confidence intervals (CI), which, if standardised, would have stretched the estimation range to roughly 900-1,900 tigers.

Beyond the smokescreen of these technicalities, the planners, it seems, sought to sidestep the enormity of the exercise. Often the sample size was compromisingly small and the extrapolation scientifically unsupportable. For example, the WII used about 100 cameras this time to cover just 120 sq km of the Nagarjunasagar-Srisailam tiger reserve in Andhra Pradesh. Only seven tigers were identified in that area. Based on these seven tigers over 120 sq km, the estimate extrapolated a figure not only for the 3,568 sq km reserve but the entire Western Ghats of the state.

It wasn’t just dubious science, even the equipment and management were shoddy.

The WII used around 500 camera traps for the second all-India estimation. Several officials admitted that about 300 camera traps malfunctioned. The official stand remains that the premier institute got the faulty sets replaced and reinstalled. Officials also claim this caused a procedural delay of about two months.

Sources in the field, however, report a very different picture. In Corbett, around 60 camera traps were installed in two phases (pre and post-monsoon) last year. Within days of installation, the Corbett ground staff cautioned the WII team that most cameras had an activation lag. Meaning the camera would react late and click after the animal was gone or when only its hind portion was in the frame. The young WII field team tried to overcome the handicap by altering camera angles to obtain a wider focal field but that did not solve the problem when animals walked by too close to the camera.

In Maharashtra’s Tadoba tiger reserve, around 60 cameras turned out to be faulty when pre-monsoon camera-trapping began last year. When WII personnel returned with replacements after the monsoons, they barely spent a month in the field. The same problem delayed field installation in several reserves where camera traps reached as late as November 2010.

If high-profile reserves were covered so shoddily, imagine the fate of less known, newly notified tiger reserves. Few non-reserve areas were adequately camera-trapped, not to mention the tiger-bearing forests outside Protected Areas (PAs).

For example, not a single camera trap was set up in Tadoba’s Kolsa range, leave alone areas outside the reserve notorious for human-tiger conflict. In Jharkhand’s Naxal-infested Palamu tiger reserve, no camera-trapping was possible and WII depended on Hyderabad-based Centre for Cellular and Molecular Biology for scat sample analyses and pegged the number of tigers at six.

A WII scientist involved in the census admitted that no camera-trapping had been done yet in at least three stretches. Even in reserves like Maharashtra’s Melghat, sources say, the camera traps are yet to conclude the “recapture process” crucial to statistical extrapolation.

Granted, as a top WII scientist puts it, the camera traps with all their faults have recorded more than 600 tigers across the country. Anyway, the tiger is on a marginal rebound. Protection has improved in many pockets and with so many cubs reported in the past four years, a nominal rise in the tiger population was to be expected.

There are other reasons too for the count to increase. In the first national census of 2006-07, bizarre examples of ill-trained field staff unwittingly under-reporting tigers probably compensated for any over-reporting of numbers. For example, field staff in Uttarakhand’s Ramnagar forest division went for pugmark identification and failed to report each individual tiger track in 2007. Eventually not more than half a dozen tigers were estimated in the entire division. This year, a WWF (World Wildlife Fund) team used its own camera traps and, say sources, as many as 23 tigers have been estimated. That is a near 300 per cent jump, if on an exaggeratedly low base caused by tigers left out in the previous count.

But why does a census operation that cost Rs 13 crore four years ago (nobody has spelt out the cost of the most recent exercise yet but it could not have come cheaper than the last census) and had four long years to iron out the creases, end up being so disorganised and scientifically compromised?

Many expected the second all-India estimation to be a far more intensive exercise in terms of camera-trap intensity or number of camera nights utilised. But WII followed the same routine as in 2007. Blame it on inadequate manpower, lack of planning and faulty camera circuits or plain inertia, the exercise stuttered at different stages. Given that Aranyak, an NGO, did a fantastic job at Kaziranga using WII camera-traps, it is a mystery why the government did not try to rope in more NGOs elsewhere.

For reasons best known to WII, it continues to buy analog cameras from a manufacturer that few user agencies endorse internationally. WII opted for the obsolete Moultrie camera traps that need a recovery time (from sleep to click mode) of 60 seconds. Maybe, our sarkari scientists expect tigers to stand still and be counted in the national interest.
When replacements arrived for faulty sets, were these installed and allowed enough field time to ensure uniform parameters across landscapes? If a dubious purchase and deployment had already delayed the results, what was the hurry to declare numbers with “three stretches yet to be covered”? Were the minister and his bureaucrats desperate to score a few brownie points at the high-profile international summit?

This leads us to another mystery. But, first, a brief backgrounder. In June 2008, the World Bank launched its tiger conservation initiative with much fanfare at Washington DC. India, the most crucial of the 13 tiger range countries, was absent.

It was no coincidence. On the back of a note from the Ministry of Environment and Forests, the PMO had refused to endorse the Bank’s initiative and ruled out seeking a loan to save the tiger. The Bank was told that it did not have the expertise or support of (at least Indian) experts to substantially back any tiger conservation effort. On the contrary, much of its history—from the destruction of the Amazonian wilderness to wiping out Asian mangroves—made its tiger overtures appear plain opportunistic. India’s own dismal experience with the Bank-sponsored eco-development projects in the 1990s had also influenced the PMO’s decision.

But in less than three years, the Bank has reclaimed centrestage, with seven of its top officials—among them three Indians—dominating the proceedings at the March 28-30 New Delhi gala. How did the PMO suddenly change its stance? And how come the ministry that advised him against allowing the Bank in tiger conservation is now toasting the Bank’s who’s who?

The ministry’s advice to the PMO was shaped largely by the views of experts outside the government. The minister himself had made it amply clear in 2008 that he was not against accepting the Bank’s help (read: loan) but had been dissuaded by the collective wisdom of conservationists. So has this mighty consensus suddenly reinvented itself?

The Bank sponsored a host of tiger stalwarts and budding greenies from India at the international tiger conservation forum in St Petersburg last November. But a single junket, however lavish, could not have turned the tide in the Bank’s favour. Only weeks ago, the Planning Commission drastically slashed the allocation for tiger conservation. Was that move aimed at preparing the ground for a loan? You never know what a few old Bank boys can get up to.

About The Author

Jay Mazoomdaar