Articulos

One of nature’s most perfect killing machines dozes in the afternoon heat. We watch the cat sleep as other jeeps crowd around us like a pack of dholes, the wild dogs that hunt inside the park. People gasp and point, then click their cameras from the safety of their vehicles. Slowly, the tiger opens one eye, and with a casual glance in our direction, locks me in a gaze so powerful that all elsedisappears. After licking its paws and stretching its back, the cat rises to its feet. Then the tiger turns its head and walks deeper into the forest until it disappears.
From the boreal forests of the Russian Far East to the jungles of Sumatra, tiger populations are in free-fall. In the past century, their numbers have plunged from an estimated 100,000 to fewer than 3,500.
This small pocket ofsouthwestern India is one of the few places where the tiger popula- tion has reversed the trend and is now strong. Biologists and government officials from all over the world are visiting Nagarhole to learn from Karanth; he gives them hope that they can save their own tigers and other big cats.
Karanth, 63, grew up less than 100 miles from here and first visited Nagarhole (also known as RajivGandhi National Park) in 1967 as a teenager. Hunting and logging were rampant in the park at the time. Seeing even a chital, the small spotted deer now found in droves throughout the park, was rare. “I was pretty sure I would never see a tiger by the time I grew up,” he says.
Karanth went on to study mechanical engineering and then bought a plot of land to farm near Nagarhole so he could be an amateurnaturalist in his spare time. In 1984, he entered a wildlife management training program at what is now the Smithsonian Conservation Biology Institute in Front Royal, Virginia. Karanth earned a PhD from Mangalore University studying tigers inside Nagarhole. He now works for the New York-based Wildlife Conservation Society (WCS), combining the cool objectivity of an engineer with the passion of alocal boy who never tired of looking for tigers. Since he began monitoring the population in 1990, tiger numbers in Nagarhole have climbed from fewer than 10 individuals to more than 50. More important, the park is a source of young tigers: Cubs born here are leaving the park and repopulating the surrounding forests. “There are now 250 tigers in this region,” Karanth says. “If we do everythingright, we can have 500.”
“You have to be able to measure tiger populations with confidence, and Karanth has developed the whole tool kit to do this,” says John Seidensticker, head of the Smithsonian’s Conservation Ecology Center and one of Karanth’s early mentors.
Each year after the summer monsoons, Karanth and his team blanket the forest with hundreds of camera traps. When an animal walks past atrap, infrared sensors trigger cameras on both sides of the trail. Every tiger has a unique stripe pattern, which Karanth uses to identify individuals and estimate how many tigers live in Nagarhole at any time. He has collected more than 5,000 tiger photographs.
He has found that one out of four adult tigers in the park dies or disperses into the surrounding forest each year. In the past fouryears, he says, he documented 40 deaths in the area that includes Nagarhole, Bandipur and several other reserves. But he’s not worried. “If reproduction is up,” he says, “this is not a problem.”
What affects tiger reproduction? The answer might seem simple, but it took Karanth nearly ten years to collect the data to confirm a direct relationship: The more animals available for tigers to eat, themore they reproduce. “The forests were empty not because the tiger had been hunted out, but because their prey had been,” Karanth explains.
The realization has significant implications for how to protect tigers. Many conservation authorities focus on stopping big-game poachers, who kill tigers and sell the body parts for high prices on the black market. (Tiger bone, for instance, is promoted as a...