More and more restaurants are dropping Japanese "gin mutsu" bluefish from their menus as environmentally certified fishing and seafood products become popular in Japan.
The London-based Marine Stewardship Council is trying to universally certify seafood from resources that are not threatened by overfishing.
The World Wildlife Fund began approaching Japanese fishery cooperatives and distributors this year to sell MSC-certified seafood. Industry sources have said the sale of such marine products might begin before the end of the year.