A Tale of Two Nearly Extinct Giant Salamanders

In Japanese rivers, if you’re very lucky, you might find unusual amphibians that grow up to five feet long and look like strange cartoon dinosaurs. They are giant salamanders.

“Salamanders are big, and they’re cool,” said Sena Ishikawa, a master’s student studying the animals at Kyoto University. “I just love them.”

Such passion for the slippery species, which Japan has designated a “special national treasure,” prompted Ms. Ishikawa and two other students to set out on an unseasonably cold evening in March along the Kamo River in Kyoto, wearing headlamps, waterproof overalls, knee-high rubber boots and neon yellow safety vests, and carrying what looked like oversize butterfly nets.

The three students weren’t just looking to capture any large salamander: Their goal was to find a purebred Japanese giant salamander.

For those who know where to look, it’s not difficult to find giant salamanders in Japan. But they typically are not the large amphibians native to the country. The unplanned release in recent decades of giant salamanders from China has resulted in a rising number of hybridized animals of Japanese and Chinese descent. These blended animals have become a bane for Japanese conservationists who wish to protect the genetic integrity of their endemic species, which is considered to be vulnerable to extinction.