Photo: The Ady Gil collides with Japanese whaling ship Shonan Maru Jan. 6, 2010.
The anti-whaling group's vessel, a former racing ship, was used to "intercept and physically block the harpoon ships from illegally slaughtering whales" according to the group's founder Paul Watson.
The Japanese Whaling Association has called Sea Shepherd "a terrorist group" in the past.
Photo: Sea Shepherd Conservation Society activists aboard the Ady Gil hold a projectile launcher and a camera.
The society said its vessel was hit first by the Japanese ship the Shonan Maru near Commonwealth Bay and had about 10 feet of its bow knocked off.
Locky Maclean, the first mate of the society's lead ship, said one crewman from New Zealand appeared to have suffered two cracked ribs, but the others were uninjured. The crew members were safely transferred to the group's third vessel, though the Ady Gil's captain remained on board to see what could be salvaged, he said.
Photo: Ady Gil crewmembers aim a projectile launcher during their encounter with the Japanese whaling ship Nisshin Maru Jan. 6, 2010.
The group accused the Japanese ship of deliberately ramming the Ady Gil.
"They were stopped dead in the water when the incident occurred," Maclean said of the Ady Gil. He spoke by satellite phone from the ship, the Steve Irwin.
"When they realized that the Shonan Maru was aiming right for them, they tried to go into reverse to get the bow out of the way but it was too late. The Shonan Maru made a course correction and plowed directly into the front end of the boat," he said.
Photo: Game show host Bob Barker donated $5 million to the Sea Shepherd Conservation Society.
VIDEO COURTESY OF AP
Glenn Inwood, a New Zealand-based spokesman for the Institute of Cetacean Research, the Japanese government-linked body that carries out the hunt, disputed Sea Shepherd's account, saying video shot from the whaler showed the conservationists' boat moving toward the whaler just before the collision.
"The Shonan Maru steams to port to avoid a collision. I guess they, the Ady Gil, miscalculated," Inwood said. "Sea Shepherd claims that the Shonan Maru has rammed the Ady Gil and cut it in half — its claim is just not vindicated by the video."
The boat's six crew members were safely transferred to another of the Sea Shepherd Conservation Society's vessels, the newly commissioned Bob Barker. The boat is named for the American game show host who donated $5 million to buy it.
The clash was the most serious in the past several years, during which the Sea Shepherd has sent vessels into far-southern waters to try to harass the Japanese fleet into ceasing its annual whale hunt.
Clashes using hand-thrown stink bombs, ropes meant to tangle propellers and high-tech sound equipment have been common in recent years, and crashes between ships have sometimes occurred.
Japan's Fisheries Agency said it was still checking details about the clash. Spokesman Toshinori Uoya said there were no injuries on the Japanese side.
It was not immediately clear what would happen to the Ady Gil. Sea Shepherd said in a statement posted on its Web site that the boat was "believed to be sinking and chances of salvage are very grim."
Wednesday's confrontation with whalers marked the first for the 1,200-ton Bob Barker, which rescued the crew.
Sea Shepherd only recently bought the ship after its namesake, the former host of the "The Price Is Right" game show and a longtime animal rights activist, donated the money. Barker met Sea Shepherd founder Paul Watson through a fellow activist and said he was instantly impressed.
"He said he thought he could put the Japanese whaling fleet out of business if he had $5 million," Barker recalled. "I said, 'I think you do have the skills to do that, and I have $5 million, so let's get it on,' so that's what we did."
Barker, 86, said he was "genuinely proud" to be associated with Sea Shepherd.
The Ady Gil, meanwhile, clashed earlier Wednesday with another Japanese ship, the whaling fleet's mothership, the Nisshin Maru.
The Institute of Cetacean Research said the Ady Gil came "within collision distance" of the Nisshin Maru's bow and repeatedly dangled a rope in the water that could have entangled the ship's rudder and propeller.
The Ady Gil's crew lobbed small projectiles designed to release a foul smell, and the whalers responded by firing high-powered hoses to keep the Sea Shepherd vessels away, the institute said in a statement.
"The obstructionist activities of the Sea Shepherd threaten the lives and property of those involved in our research, are very dangerous and cannot be forgiven," it said.
Maclean, the Ady Gil's first mate, confirmed the earlier clash.
Sea Shepherd Conservation Society currently has a television series called "Whale Wars" which appears on the Discovery Channel.