Our open Jeep fishtailed along muddy roads through northeast India’s Kaziranga National Park. A herd of deer sounded their chirping alarm call and fled. We pulled into a clearing beneath a silk cotton tree, and a massive male Bengal tiger emerged from a wall of elephant grass. He sauntered across the expanse and disappeared on the other side.

That was 2008, and I was in India to report on a shocking new census: 60 percent of the nation’s tigers had vanished during the previous five years.

But that wasn’t really the case: Previous estimates of their numbers had been vastly overestimated. This was the first time the Indian government had used the scientifically sound camera-trapping method to count tigers, remotely capturing images