Aquaculture for all

Yamanashi to Farm Newly Found Endangered Salmon

Salmonids Sustainability Breeding & genetics +5 more

JAPAN - The Yamanashi Prefectural Government plans to raise an endangered deepwater salmon species discovered in 2010 in Lake Saiko at the foot of Mount Fuji 70 years after it died out in its original habitat 500 km northeast in Akita Prefecture's Lake Tazawa.

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Yamanashi Prefectural Fisheries Technology Center culturists will gill-net the "kunimasu" species in the 2.1-sq.-km lake, collecting sperm from males and eggs from females for fertilisation at a hatchery in February and March, peak mating season, Kiyoshi Mitsui, the center's director told the TheJapanTimes.

The kunimasu was classified as a new species in the genus of Pacific salmon in 1925 by David Starr Jordan, a US ichthyologist and the first president of Stanford University, and Ernest McGregor, another ichthyologist, in the authoritative Memoirs of the Carnegie Museum.

The two described the species as "another landlocked derivative" of the sockeye. The fish, being almost black, lives at a considerable depth and has a smaller number of pyloric caeca, finger-shaped pouches used to digest food, than other landlocked variants of red salmon.

The Japan Times reports that the species was last seen in Lake Tazawa in 1940, when water made acidic from a hydroelectric power project was introduced into the lake from a nearby river.

Consequently, the species died out in the lake. It is still listed as extinct in the Environment Ministry's Red Data Book for endangered and extinct species. The ministry now says it may reclassify the kunimasu when it updates the list in fiscal 2012.

In promoting the aquaculture project, Yamanashi Gov. Shomei Yokouchi has called the rediscovery of the kunimasu "a real drama."

Emperor Akihito, an ichthyologist himself, called the species "a miracle fish" and said in December 2010, "It is absolutely necessary to disperse the risk so that the kunimasu will not become extinct in the future."

Mr Mitsui, with the Yamanashi fisheries center, said the local government wants to farm the kunimasu to make it "a signature marine product of Yamanashi Prefecture."

The center's technology will enable about 80-90 per cent of fertilised eggs to develop eyes, and approximately the same percentages of those eggs to hatch to become sac fry, or alevin, Mr Mitsui said, adding, "If we can collect 300 eggs, we would be able to obtain some 150 to 200 fry."

"If we conserve the kunimasu with artificial fertilisation, we will enable it to continue to exist, even if the current good conditions in Lake Saiko might cease to exist in the future," he said.

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