A diplomatic crisis is looming over an anti-whaling protestor who is reportedly being held in custody on a Japanese whaling vessel.

Japanese whalers have confirmed a New Zealand protester who boarded one of their ships has received medical attention for a knife-wound.

Two Sea Shepherd activist ships say they are in pursuit of the Japanese whaling fleet in the Southern Ocean, exchanging water cannon fire with the whalers.

Something is holding down the herring population of Alaska's Prince William Sound, and marine scientists are tailing some rather large suspects: humpback whales.

Japanese whalers and anti-whaling group Sea Shepherd are once again pointing the finger at each other after a collision at sea.

John Key says progress has been made on a deal which would end Japanese whaling in Antarctica.

The Sea Shepherd Conservation Society today filed with NZ police a complaint of attempted murder against the captain of a Japanese whaling ship.

Sea Shepherd national coordinator Bill Watson has called for Foreign Minister Murray McCully to step down from his portfolio.

The New Zealand Government is taking a passive role while Kiwi lives are put at risk and Japan's whalers get a green light, says Labour MP.

Anti-whaling protesters say Japanese whalers ignored distress calls after the Ady Gil was severely damaged during a collision.

The NZ anti-whaling vessel half-destroyed when it and a Japanese whaling harpoon ship collided is too damaged to be salvaged.

An international law expert says anti-whaling protesters were 'at the very limit and edge of the law'

The NZ Government has called for restraint after an anti-whaling protest vessel and Japanese harpoon ship collided in Antarctica yesterday.

The crew of a NZ trimaran harassing Japanese whalers have been rescued after a collision between their boat and a Japanese ship.