The International Herald Tribune is reporting that the Emperor of Japan is expressing much regret over his decision to accept a gift of live bluegill (Lepomis macrochirus) from the United States. He brought the fish home in 1960 and, with the hope that he could cultivate them as a food fish, gave them to Japan's Fisheries Agency. Researchers there then bred the fish and released many of them into Lake Biwa. Unfortunately, bluegill numbers eventually got out of hand, and the native fauna of the lake has since declined. With peak populations of the non-native fish topping 2 million in 2002, Japan has been forced to spend millions of dollars removing bluegill from the lake.
Tip of the virtual hat to the annotated budak for sending in a link to this story.