A Japanese whaler is missing believed drowned after falling overboard in the freezing waters of the Southern Ocean.

Hajime Shirasake, a 30-year-old engine room oiler, was reported missing from the whaling ship Kyoshin Marus No. 2 when he did not turn up for his shift early on Monday. He was believed to have been washed overboard in heavy swells measuring 12 feet, while dressed only in overalls.

An alert was issued to ships in the area but Maritime New Zealand's Rescue Coordination Centre called off a search today after ascertaining that the area where Mr Hajime disappeared was too far for an aerial search, while sub zero temperatures meant it was unlikely he could survive.

An aircraft would have taken about 10 hours to reach the site, but with survival time in the zero-degree water a mazimum of one hour, the plane would arrive too late to rescue Mr Hajime, said a spokeswoman for the centre.

"We've suspended the search, we're not going to be involved any further," said Sophie Hazelhurst, from the MNZRCC.

Japanese whaling ships were still looking for the sailor, despite the official search being called off, a whaling spokesman said.

Japan's whaling fleet is in the Antarctic for its annual hunt, disguised as scientific research to get around an international ban on whaling.

The Sea Shepherd anti-whaling group which has been chasing the fleet, and might have been in a position to rescue Mr Hajime, temporarily abandoned their pursuit in the weekend while their ship, the Steve Irwin, returned to port to refuel.

It is the second death in two years for the whaling fleet after a crewman on board the factory ship Nisshin Maru was killed in a fire in 1997.

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