Japan’s environment ministry on Friday added Japanese eel to the “Endangered” category of its Red List for endangered fish living in domestic rivers, marshes and lakes, indicating the species faces a high risk of extinction in the near future.

The “Endangered” category is the middle of three subcategories under the “Threatened” category. Amami rabbit and raicho grouse are also classified on the same alert level.

Annual catches of Japanese eels have faced record lows in recent years, declining to 5 percent of their levels in the 1960s.

Resource protection measures such as stricter eel catch controls are necessary to protect the Japanese eel, which is indispensable to the nation’s food culture, observers said.

Japan consumes about 70 percent of all eel eaten worldwide.

The number of “Threatened” species reached 167, out of about 400 species under watch, and about 40 percent of fish species living in fresh and brackish water environments are threatened with extinction, the ministry said.

Overcatching, loss of habitat due to development projects and changes in sea currents are suspected causes of the eel population decline.

Moreover, little is known about the Japanese eel’s ecology. In the Red List revision six years ago, the species was classified in the “Data Deficient” category.

Based on recent ecological studies and catches, the ministry reevaluated the estimated population. It found the rate of decline for the most recent three generations of the species to be from 70 percent to 90 percent. Therefore, the ministry designated the species as endangered.

As the Red List has no legal binding authority, catches of Japanese eels cannot be immediately regulated. However, the Fisheries Agency aims at recovery through such measures in the future.

Japan imports large quantities of eel, including Japanese eel, from China and Taiwan. The agency plans to hold active talks with Chinese and Taiwan fisheries authorities to prevent overcatching.

Japanese eel, or Nihon unagi, is one of 19 eel species known worldwide. It inhabits central Hokkaido and areas to the south of it.

According to the Red List on shellfish announced last summer, hamaguri, or common orient clam, was classified into a Threatened category.

Other threatened species related to the Japanese food culture include nigorobuna, a species of Japanese crucian carp, and mirugai trough shell.


Kunimasu survives ‘extinction’

Kunimasu deepwater trout, a salmonid species specific to Lake Tazawa in Akita Prefecture, had been classified as extinct until Friday’s revision of the Red List. It is now listed as “extinct in the wild,” having been discovered in Lake Sai in Yamanashi Prefecture in 2010 for the first time in about 70 years.

Kunimasu were once discharged into the lake, one of the five lakes around Mt. Fuji.

Red Lists for nine categories of living creatures, except fish species, were revised in August. With completion of the revised Red List on fish species, all the fourth versions of the 10 Red Lists are now finished.

The number of species in the “Threatened” category increased by 442 to 3,597 in the fourth set of lists. The lists were first announced in 1991.

By News Desk

(The Yomiuri Shimbun)