Or at least ate Japan's fish. The problem is so bad that the Emperor is apologizing for bringing bluegill into Japan in the 1960s.
Chicago mayor Richard Daley gave bluegill, the state fish of Illinois, as a gift to the current Emperor in 1960. Hoping to create a new delectable food source, Japanese fish biologists established the bluegill in lakes. Now, bluegill are eating and depleting some native species, and they've become an official nuisance. "Its cultivation started as there were great expectations of raising them for food in those days. My heart aches to see it has turned out like this," Emperor Akihito said.
To control the bluegill, there is a "catch and eat" policy for bluegill. Who knew that these nice little fish could be such a scourge. How long until we have a Bluegillzilla horror movie?