November 13, 2007
Emperor takes the blame for bringing killer fish to Japan
Japanese Emperor Akihito (L) and Empress Michiko strolling through a garden at the Imperial Palace in Tokyo
The Emperor of Japan expressed “heartfelt distress” yesterday for the release of an aggressive American bream into the country’s largest lake, amid growing national concern at the fate of native species.
Emperor Akihito appeared to take responsibility for the introduction to Japan of the American bluegill, whose fierce appetites have caused the extinction of the prized Japanese rosy bitterling.
Emperor Akihito, who was presented with the fish in 1960 as a gift from the Mayor of Chicago, told an audience of marine life experts and environmentalists to “keep a close eye on the creatures of Lake Biwa” so that native breeds would never become extinct again.
But according to the Japanese Environmental Agency, it may already be too late because of the bluegill’s extraordinary breeding power.
National emotion on the subject of alien fish runs high since most of Japan’s lakes and rivers are now overrun with the bluegill. By 2000 the fish had spread throughout the country.
But the bluegill presents a very personal challenge to the Emperor. Not only is Akihito a keen student of marine biology – he is a member of the Linnean Society of London – but the moats of his own palace are also infested with bluegills.
A 1999 report on the state of the 13 moats around the Imperial palace found that eight were plagued by alien species, including the bluegill.
The problem began nearly 50 years ago with what appeared to be a straightforward visit to the United States. Then still the Crown Prince, the young Akihito was on his first foreign excursion since his marriage. He was shown all the usual hospitalities – dinner at the White House, baseball and a trip to Disneyland – but also, given his interest in marine biology, managed to include a detour to the Chicago Aquarium.
It was here that the young prince was given the gift that would transform Japan’s lakes and waterways.
The early 1960s were an era of protein shortage in Japan and the bluegill, the Emperor discovered, was delicious. He gave the fish to the Institute of the Fisheries Agencies expressing the wish that it be considered as a source of food. The fish was for some years farmed under experimental conditions, but somehow it reached the outside world eventually.
Nobody is sure how or when the fish escaped but in a 1977 edition of the Japanese magazine Freshwater Fish, a journalist noted that the bluegill had made its appearance in Lake Biwa. By the 1990s the population exploded.
“It was strongly expected that the fish could be a source of food . . . but I now feel heartfelt distress that it has led to such results,” said the Emperor.
The Emperor’s comments come at a time of heightened “ecological nationalism”. Over the years Japan has allowed a number of foreign species of plants and animals on to its shores and many have proved to be destructive. Many make their way in as pets: exotic snakes and lizards are regular offenders, but the Japanese craze for beetle-collecting has also taken its toll.
Restrictions on beetle imports were relaxed about seven years ago, and in 2005 more than a million beetles were imported to Japan - about 150 times more than in 1999.
In 2006 Japan passed the Invasive Alien Species Act but it has utterly failed to prevent, for example, the march of the European dandelion.
Have your say
With all due respect to his Highness, he should have done his research before bringing these fish to his country. Alternatively someone at the aquarium should have warned him about their being released in alien aquacultures.
Down in Texas we know that Bluegill breed like rats and are about as voracious. They're basically piranha without the denture work! I know of one pond down here north of Houston that if you fall in, you likely won't be coming back out with all your flesh for the bluegills and other perch!
Todd, Houston, Texas
December 9, 2007
The Emperor of Japan's Rosy Bitterlings
Sir, I have been assisting His Majesty’s research on gobioid fishes for almost 40 years and would like to draw your attention to some factual inaccuracies in the article “Emperor takes the blame for bringing killer fish to Japan” (Nov 13 ).
The article indicates that the introduction of American Bluegills into Lake Biwa, with their fierce appetite for Rosy Bitterlings, has prompted the extinction of the latter. However, it was authentic Japanese Rosy Bitterlings that became extinct, not because they were eaten by American Bluegills, but because of hybridisation and competition between Japanese Rosy Bitterlings and Continental Rosy Bitterlings, which had been introduced into Japan from China in the 1940s, and were bigger in size than Japanese Rosy Bitterlings. Today only Continental Rosy Bitterlings live in Lake Biwa and its connected water systems.
Alarmed by the impending extinction of Japanese Rosy Bitterlings, His Majesty, then the Crown Prince, advocated prompt research on the plight of Japanese Rosy Bitterlings in their natural habitat and also started working on preservation of the species in a pond in the Akasaka Imperial Garden ensuring that no Continental Rosy Bitterlings be released in the pond. As a result, Japanese Rosy Bitterlings have been bred, and are utilised as specimens for taxonomical and genetic research. Today Japanese Rosy Bitterlings are found in ponds in the western part of Japan where Continental Rosy Bitterlings have not been introduced.
I should also like to point out that His Majesty is not a marine biologist as described in the article, but an ichthyologist specialising in gobioid fishes that live in the sea and in rivers. The number of species of the gobioid fishes in Japanese waters is now over 400.
Chamberlain to H. M. The Emperor