Fish Thought to Be Extinct for 70 Years Rediscovered


Photo credit: skyseeker/Creative Commons

In 1940, a hydroelectric dam was constructed in northern Akita Prefecture, Japan. The project, it was known at the time, would destroy the only native habitat of the black kokanee salmon by making the waters too acidic for the fish to survive. Still, developers went ahead with their plans.

A concession was made to protect the species: 100,000 eggs were transported to nearby Lake Saiko. Unfortunately, the transplanted eggs did not hatch and the species quickly became extinct. At least, that's what was thought.

Now, a new discovery suggests that a small population of kokanee salmon may have survived."I was really surprised," Tetsuji Nakabo, a professor at Kyoto University who led the team that made the discovery said, "this is a very interesting fish—it's a treasure. We have to protect it and not let it disappear again."

The extant population was uncovered in Lake Saiko—the same place the eggs had been deposited 70 years prior—and the population had grown large enough as to be sustainable.

Sustainable, that is, as long as the environment in and around the lake can be maintained. Lake Saiko, Nakabo explained, is a popular destination for tourists because of the views of Mount Fuji from its banks. A sudden influx of fisherman, especially, could threaten the survival of the fragile species.

In Japan, the salmon is not alone: Other species, including shellfish and plants have been rediscovered since being declared extinct. The official list of extinct species in Japan is set to be revised in 2012.

Read more about extinctions:
Life on the Endangered Species Waiting List
The Sixth Extinction is Underway: Are You Worried Yet?
Read more about species rediscoveries:
Extinct Frog Rediscovered in Australia
'Extinct' Spider Rediscovered in England
Rare Dwarf Lemur Rediscovered in Madagascar
Rare Bumblebee Species Rediscovered in Scotland after 50 Years

Tags: Animals | Conservation | Endangered Species | Fish

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