Japense whalers are suing activists Sea Shepherd in a bid to protect their 'research' activity.

The Japanese research institute responsible for the country's whaling is suing anti-whaling activist group Sea Shepherd.

The Institute of Cetacean Research has filed a lawsuit in the United States to protect its research whaling vessels and crews against physical attacks by the Sea Shepherd.

Kyodo Senpaku, the owner of two whaling vessels contracted by the institute, has also joined the action.

The parties are seeking a court order in the district court in Seattle, Washington, to prevent Sea Shepherd and its founder Paul Watson from engaging in activities at sea that are or could cause injuries to the crews and damage to the vessels.

Sea Shepherd is based in Friday Harbor, in Washington State. The whaling takes place in the Southern Ocean in Antarctic waters 3000 kilometres southeast of New Zealand.

A spokesman for the Japanese whalers said in recent years Sea Shepherd’s attacks had become increasingly violent.

Projectiles fired from Sea Shepherd vessels had caused injuries to several Kyodo Senpaku crew members.

The spokesman said collisions by Sea Shepherd had placed the vessels at risk of being lost at sea.

"Sea Shepherd has made numerous attempts to foul ships’ propellers with ropes, potentially placing the crews and vessels in extreme danger. Last season’s research was cut short because of heightened concerns for the safety of the crews and vessels.

"The plaintiffs support the right to legitimate and peaceful forms of protest and demonstration, and the lawsuit makes no attempt to curtail this right. Instead it seeks to establish clear legal boundaries between legitimate/ peaceful protest and illegal/ violent sabotage."

Sea Shepherd Conservation Society founder and president Paul Watson said he found it amusing the Japanese could ''destroy a vessel, shoot at us, toss concussion grenades at us, ram us and attempt to kill us and then they file a lawsuit against us.



"Of course with a war chest of $NZ30 million plus to work with they can pursue numerous strategies. It will not deter us.



"We are not protesting whaling. We are opposing an illegal activity. We will respond accordingly in the United States courts if such is the case," Watson said.

The Japanese ships harvest whales claiming the catch is for research purposes, conducted under a special permit granted by the Japanese government under Article 8 of the International Convention for the Regulation of Whaling.

Acrimony between Sea Shepherd and the Japanese vessels has escalated in recent seasons with allegations of violence from both sides. Last season Sea Shepherd claimed it was pursued by Japanese ships attempting to blockade the protest vessels and prevent them from approaching whaling ships.

In 2010, a Sea Shepherd boat sank after its bow was sheared off in a collision with a whaling ship.

The whale-hunting season runs from about December to February.

-Fairfax NZ