HUAI KHA KHEANG WILDLIFE SANCTUARY, Thailand — After trudging through the wilds of western Thailand for several hours, the forest rangers thought they were finally onto something: the distant sound of crunching leaves.

Automatic weapons drawn, the five Thais crept forward, hoping to catch a tiger poacher. It turned out to be a banteng, a wild cow, which disappeared into the woods.

But all in all, the absence of illegal hunters was good news, said ranger Sakchai Tessri. “When we passed before, we would always run into poachers.” Now he felt their room for maneuver was narrowing.

“In the old days,” he said, “they would spend many nights in the forest for poaching. Now they just come in, shoot, grab and go quickly.”

The 6,400-square-kilometer (2,500-square-mile) Huai Kha Kheang and Thung Yai Wildlife Sanctuaries on the Burmese border represent a rare success in the struggle to save the world’s dwindling tiger population.

Irrawaddy