Japan in Culinary Offensive to Stop Spread of Us Fish

The keepers of Japan's biggest lake have called on the public to join in one final push to eat the bluegill fish - possibly the most reviled creature in Japan - into extinction before it does the same to threatened native species.

The bluegill's steady destruction of indigenous freshwater fish, almost 50 years after it was touted as a vital source of protein for an undernourished population, is being treated as an ecological emergency and has provoked a rare public show of contrition from Emperor Akihito. As crown prince, Akihito received bluegill as a gift from the then mayor of Chicago, Richard J Daley, during a visit to the US in 1960.

"Bluegills are the ones I brought back from the US almost 50 years ago and donated to a fishers agency research institute," the emperor said earlier this month. "In those days we had great expectations of raising them for food. My heart aches to see it has turned out like this."

Now authorities in Lake Biwa in Shiga prefecture want anglers to stop releasing the fish and instead eat them. Biwa, the world's third-oldest lake, is home to about 1,250 tonnes of bluegill; nationwide, the population is estimated at 25m fish.

Though considered a delicacy in Illinois and other parts of the US, it has struggled to find favour among Japanese diners. The Shiga government recommends marinating bluegill or serving it deep-fried with a chilli sauce garnish.

A local university will soon start selling bluegill burgers, and one firm is experimenting with a version of funazushi - a local delicacy of salted crucian carp and rice that is left to ferment for three years.

The fish brought back by the emperor were donated to research centres, but many escaped to wipe out the royal bitterling and bring other native species to the brink of extinction. They have infested waterways across Japan, including the moat of the imperial palace in Tokyo. A multimillion-yen campaign to turn them into fertiliser and chicken feed has had limited success.