Australia-based environmental activist group Sea Shepherd has claimed it has saved 750 whales from the harpoons of the Japanese whaling ship. The group has returned to shore after their longest anti-whaling efforts in the Southern Ocean.

Bob Barker and Steve Irwin, Sea Shepherd's anti-whaling ships, have docked in Wellington and Hobart on March 22 after being away from land for 94 days. Sea Shepherd's return has formally ended its annual anti-whaling campaign against the Japanese harpoon fleet.

Peter Hammerstedt, captain of the Bob Barker, said the Japanese whaling fleet has not yet released the total number of whales they have "killed." However, the Sea Shepherd crew is confident that the Japanese harpoon fleet has not reached a quarter of their quota. Mr Barker estimated that 750 whales were saved from the annual Japanese whale hunt.

Sea Shepherd has claimed the Japanese whaling ship "attacked" its ship in the dark in what it described as a "ruthless assault."

According to reports, the Japanese whaling fleet had allegedly disabled the Sea Shepherd ship in the Southern Ocean. The anti-whaling organization based in Australia said two Japanese whaling ships had ambushed its ship, Bob Barker, on Feb. 23. The Japanese whaling ships had reportedly tried to jam the Bob Barker's propellers and rubbers.

In an open letter to Australian Environment Minister Greg Hunt, the Sea Shepherd captain urged the minister to fulfill his promise during the elections and allow an observer ship in the Southern Ocean. Claims and counterclaims have been made by Sea Shepherd and the Japanese whaling fleeting after their clash in the Southern Ocean. Sea Shephered said a bamboo spear was thrown at the Bob Barker to damage the ship.

Sea Shepherd has been the chasing the Japanese whaling fleet and has recorded footage of its ships catching and killing whales. The images were taken from a helicopter and showed the Japanese Antarctic whale hunt and a dead minke whale after Japanese whalers harpooned it near the tail. The footage revealed the dead whale on the deck of Japanese whaling ship, Nisshin Maru.

Captain Hammarstedt said, the footage was one of the "cruelest hunts known to man." In local reports, Australian Antarctic Division Chief Scientist Nick Gales said two-thirds of whales caught by Japanese whaling ships die slowly.