Learn OBIRAME

2022/01/12

©Satoshi Adachi
OBIRAME is the local name of the Japanese Huchen lives in the Shiribetsu River. ©Satoshi Adachi

Where are they ?

Habitats of ITOUJapanese Huchen live only in the northeast area of Asia, and only Hokkaido island in Japan. They are born in the upper stream of the river, and go down the river to grow. They can’t live with barriers in the river to stop them coming and going.

The Siribetsu River has the southernmost local population in the world.


How long ?

A Japanese Huchen 210 centimeters long was recorded in the Tokachi River in 1930’.
Seisaku Kusajima, the first chair of the Obirame Restoration Group got the biggest male OBIRAME 153 cm long on 1957 on the Shiribetsu River.
The birth length of Japanese Huchen hatching is very small. They need 5 years to grow up 50 cm.

Let’s measure their length!
Let’s measure their length with a child 7 yeas old!

The span of life

Japanese Huchen have the longest life in the salmon family. They can easily live over 15-20 years. The male is sexually mature by 4, and the female is by 6. They can attempt reproduction over and over in own life.


The diet

Japanese Huchen is a flesh-eating animal. They eat small aquatic insects when they are very young. As they grow bigger, they get other creatures such as fish, frogs and mice.


Why ITOU had been decreased?

In Hokkaido, the habitats had been decreased since 1960’ by the human activities such as the constructions of rivers and the pollution of the fresh water. We are attempting to restore the local population of the southernmost Japanese Huchen in Shiribetsu River facing extinction since 1996.