The prince, the mayor, and the U.S. fish that ate Japan

An innocent gift from Chicago to Prince Akihito in 1960 caused a decades-long ecological crisis that Japanese scientists are now close to solving.

Crown Prince Akihito of Japan looks at tropical fish in New York on Sept. 30, 1960. In the background is Christopher Coates, director of the Coney Island Aquarium. Akihito also visited New York as part of his and his wife's state visit.

When Crown Prince Akihito visited Chicago on October 3, 1960, his sole request was to visit Shedd Aquarium. Then Mayor Richard J. Daley, an avid angler, presented the prince with a gift that he scooped with a net from one of the tanks himself: 18 bluegills, the official Illinois state fish.

The 26-year-old future emperor was already a passionate ichthyologist, and he planned to stock the exotic fish in the moat surrounding his palace, according to accounts in the Chicago Tribune at the time.

At windy Chicago O’Hare International Airport the next day with Princess Michiko, Akihito bid the city farewell, carrying a gift that he couldn’t have imagined would cause a decades-long ecological crisis in his homeland.

In the intervening six decades, the bluegills became an invasive, species-destroying nightmare, crowding Japanese freshwater lakes and rivers and destroying native fish biodiversity, says Kenji Saitoh, a researcher at the country’s Fisheries Resources and Education Agency.

Fortunately, science has marched on in 60 years. Now, Japanese geneticists are experimenting with the gene editing wizardry of CRISPR to sterilize the invasive bluegills. If the initiative succeeds, wildlife managers could use the same technique to rid the U.S. of damaging aquatic invasives such as the Asian carp.

In Japan, the public is ambivalent about the bluegills and wary of genetic efforts to curtail them, and it’s easy to see why. The 60-year history of bluegill in Japan is a cautionary tale about human intervention on all sides.

The invasion begins


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