Japanese Salamander Is an Ungainly Survivor of Evolution

It’s big and slimy, with bulbous fingertips and a fat, flipper-like tail. It hides under rocks during the day and comes out to feed at night, sucking anything that passes into its wide, wart-studded mouth.

Lurking in the shallows of its river habitat, the giant salamander looks like something from a science fiction movie. But this beast is a survivor from an ancient era, one of the world’s largest amphibians at up to 5 feet long and a sovereign predator in the Asian waterways.

“It’s a real relic,” said Masafumi Matsui, a professor and amphibian expert at Japan’s Kyoto University. “This animal has hardly changed for the past 20 or 30 million years.”

For scientists, this primitive salamander found only in Japan and China, with a close but smaller relative in North America, is a key to understanding the roots of the Earth’s biodiversity.

But even though it is protected by Japanese law, the giant salamander’s days may be numbered--experts say the damming of many Japanese rivers has destroyed the rocky caverns and burrows where this salamander lays its eggs.

And many fishermen would prefer to see them go.

Fishermen in one of the salamander’s last remaining habitats recently made headlines with complaints that the animal’s unfettered breeding is cutting into the local population of sweetfish, a small fish prized by people and salamanders.

“We see the sweetfish get eaten by the giant salamander, so we know there’s damage being done,” said Takuharu Maeda, chairman of a fishing association here.

Local officials haven’t measured the size of the sweetfish population, he added, “but we know our catch is getting smaller.”

Scientists question these claims.

Takeyoshi Tochimoto, an internationally recognized authority on giant salamanders, said the animals do eat sweetfish but probably not enough to disrupt the population.

The Japanese giant salamander was put under protection in 1951, after its population was threatened by mountain people who ate it as a source of protein. Today, it’s no longer part of the Japanese diet and its population has grown, but conservationists warn that without continued protection of its breeding grounds, it could easily slip into extinction.

Tochimoto admits much about the salamander’s life is unknown. With government permission, he’s begun inserting microchips into giant salamanders in the wild to help monitor the elusive creature.

“This animal is at the top of the river’s ecosystem,” Tochimoto said. “If it survives, that means other living things are surviving as well. It’s an important environmental symbol.”

Albeit not a very pretty one.

The salamander’s thick trunk is soft and wrinkled, glistening with a sticky mucus that smells remotely like rubber. Small legs splay awkwardly from its brownish, speckled body, and its tiny, lidless eyes are almost invisible, lost among the blotches and bumps that cover its large, flat head.

But the giant salamander, which can live for more than 50 years and grows throughout its life, has other things going for it besides beauty.

It can breathe both on land and underwater, staying immersed for long periods by absorbing oxygen through its skin. It gulps almost anything--bugs, fish, mice, crabs--into its mouth with a vacuum-like action, but can go without food for days, even months. The salamander itself, on the other hand, rarely gets eaten in the wild. It’s too big.

“It’s amazing that this salamander has survived for so long,” said Noritaka Tomoda, an amateur salamander expert. “Maybe it’ll outlive humans one of these days.”