BEIJING — Kuzya, the peripatetic Siberian tiger who two months ago wandered into China from Russia, prompting an international incident of sorts over concerns he might become the quarry of Chinese poachers, has reportedly returned to his native land, at least for the time being.

Russian and Chinese conservationists on Wednesday reported that Kuzya, one of three rescued cubs that President Vladimir V. Putin of Russia released into the wild in May, had crossed the frozen Amur River that separates the two countries, according to the tracking device he wears.

Experts say there are fewer than 450 Siberian tigers left in the taiga of Russia’s far east. Across the border in China, illegal hunting has reduced their numbers to fewer than 30. Much of the demand comes from the Chinese side, where tiger parts are prized for their perceived medicinal value and a single carcass can fetch $10,000.

Mr. Putin, who has sought to soften his tough-guy image by publicly cavorting with endangered animals, has made tiger conservation one of his trademark issues. It was Mr. Putin, in fact, who pulled the rope that freed Kuzya from his enclosure and unknowingly set him on a transnational journey of several hundred miles.