Aug. 27, 2003 — For 30 years, John Varty has been watching big cats. Not just watching, but observing. Not just observing, but studying. More often than not, he wields a camera while he works. He focused it first on leopards, then on jaguars, cheetahs and lions.

Lately, he's turned his attention to tigers, a critically endangered species that's been circling the drain ever since conservation efforts began in earnest several decades ago. The world's biggest cats are in a downward spiral. Genetic diversity suffers as numbers continue to dwindle; and numbers decrease as the gene pool becomes increasingly impoverished.

Fiercely adaptable, tigers would rebound quickly, agree conservation experts, if left to their own devices. All they need are healthy hunks of habitat chock-full of big prey. But therein lies the problem: The tiger's home turf is Asia. In countries such as India, China, Vietnam, Thailand, Cambodia and Bangladesh, desperate remnant populations of tigers compete to eke out existences on degraded land, sharing scarce water and scarcer prey — namely deer and wild pig — with the most voracious and cunning predator of all: man.

Hundreds of thousands of humans live smack up against land set aside for tiger reserves and sometimes even inside them. Domestic cattle eat the grasses and villagers' eat their game. The tigers have nowhere to go except into the villages, and nothing to eat except cattle and villagers. The tigers are killed by humans in the name of self-preservation (and sometimes vengeance), and they are poached for their bone and pelts, which bring big money on the black market.

Three of the eight subspecies already have gone extinct in the last half-century: the Java, Caspian and Bali tigers. Another, the South China tiger, is all but gone; recently, it was declared extinct in the wild although a small population remains confined in China's zoos.