From this story in the UK Daily Mail:
A fish caught close the the Fukushima nuclear plant is over 2,500 times the legal safe radiation limit for seafood, the plant's operator has revealed. The company Tokyo Electric Power (Tepco) caught the fish, dubbed 'Mike the Murasai' online, in the bay close to the Fukukshima Daiichi main reactor. It was confirmed by Tepco to have amounts of radioactive cesium equal to 254,000 becquerels per kilogram, or 2540 times the limit of 100 becquerels/kg set for seafood by the government. Scientists in the region are increasingly worried that other fish in the area are feeding off these and other contaminated species. However, the murasoi specimen caught near Fukushima did not seem to show any major abnormalities in terms of its physical appearance.