The latest Indian tiger census demonstrates welcome methodological rigour.
Counting wildlife is no easy matter, especially with a wide-ranging and stealthy forest dweller like the tiger, which is in the spotlight this week. On 28 March, India announced that its tiger population, in decline for decades, has increased by 225 animals over the past four years, to a total of 1,706. The scale of the increase is open to dispute, but the announcement signals a welcome development: the beginnings of a more rigorous approach to counting the big cats.
The tiger's worldwide decline is a tragedy, and nowhere is this more true than in India, which is home to more than half of the global population, and which considers the animal a national symbol and a source of pride. Independent scientists and the government have long been at odds over how to count and protect animals in the country's 39 tiger reserves.
But in 2005, the government was forced to come to the bargaining table after the embarrassing revelation that at the Sariska reserve in Rajasthan — once a stronghold for the cats — not a single tiger was left, even though the government had claimed that between 16 and 18 tigers lived there in 2004. A review of tiger management practices, headed by fierce environmental-justice campaigner Sunita Narain of the Centre for Science and Environment in New Delhi, recommended that the government revamp its tiger census, conducted once every four years.
Since then, officials and wildlife scientists have worked in a spirit of (perhaps grudging) cooperation. The government has abandoned its previous census strategy, which relied on counting tiger 'pugmarks', or tracks, and is incorporating more-modern methods, such as camera trapping and DNA testing. It has also become more serious about defending tiger reserves from encroaching development, and involving people who live near the reserves in policing them for poachers. Although long overdue, these are huge steps in the right direction.
But are they enough to have spurred such a dramatic increase in tiger numbers — especially after many years of relentless decline owing to poaching and habitat loss? It seems unlikely. Nor would it be wise to compare older tiger counts with a census taken using new methods. What matters now is to make sure that the new techniques are scientifically rigorous enough to give accurate data for future comparisons. Some information about the methodology is available, but full details have yet to be released.
Wildlife biologists such as Ullas Karanth of the Center for Wildlife Studies in Bangalore, who has brought tigers in the state of Karnataka back from the verge of local extinction, also emphasize the need to pay closer attention to tiger populations by counting them every year rather than every four years. The tiger population is in such dire straits that a single year can make a crucial difference, and limiting the count to every four years means that worrying trends might be detected too late to do anything about them.
The Indian government has signed up to the goal, and has agreed with Karanth on a methodology. Now the annual counts must begin, with total transparency about how they are done. The numbers will help to banish wishful thinking about the status of tigers. They will also help India to be sure that it is truly doing everything in its power to bring the cats back from the brink.
Rights and permissions
About this article
Cite this article
Eye on the tiger. Nature 472, 6 (2011). https://doi.org/10.1038/472006a