Japanese salmon declared extinct 70 years ago found swimming in lake

By Danielle Demetriou


The freshwater salmon known as black kokanee once thrived in the northerly Akita region of Japan but was classified as extinct by the government in 1940.

However, a team of scientists led by professor Tetsuji Nakabo of Kyoto University has examined nine fish in Lake Saiko, Yamanashi Prefecture, and concluded they directly match the characteristics of the "extinct" salmon.

If confirmed, this would mark the first occasion that a Japanese fish species classified as extinct has been found to be alive, according to the Environment Ministry which is investigating the claims with a view to updating its classification.

The fish, also known as "kunimasu" in Japanese, once lived only in its native Lake Tazawa, Akita Prefecture, and was declared extinct in 1940 following an inflow of acidic water due to a hydroelectric project.

However, Professor Nakabo uncovered records of how 100,000 eggs of the salmon had been transported to other freshwater locations across Japan five years before it was classified as extinct.

Among the locations was Lake Saiko, around 310 miles south of its native waters, where the scientists discovered enough of the formerly believed extinct fish to sustain its future survival.

"I was really surprised," said Professor Nakabo. "This is a very interesting fish it's a treasure. We have to protect it and not let it disappear again."