In this photo released by Sea Shepherd Conservation Society, fishermen work on a boat filled with freshly caught dolphins as a diver lifts a tale from the blood-filled water in the fishing town of Taiji in Wakayama Prefecure, Japan, in this Oct. 6, 2003 file photo. Animal rights protesters have come to this village for years but failed to stop the annual slaughter of dolphins. Now, Japan's dolphin hunters face a more powerful opponent: mercury contamination.