2:00p.m. 18th November 2008

| By AAP

A Japanese whaler winches two whales aboard the factory ship Nisshin Maru in February 2008. Photo: Australian Customs Service.

The whaling season has begun with a Japanese hunting vessel leaving port for the Southern Ocean, Greenpeace claims.

The conservation group said the ship Nisshin Maru left the port of Innoshima yesterday.

Greenpeace activists unfurled a banner saying "whaling on trial" as the ship left port.

Japan has set itself a target of about 1000 whales in the Southern Ocean.

Greenpeace International Whales coordinator Sara Holden said the ship left port quietly, without the usual fanfare that accompanies the start of the season.

"Constant pressure on Japan's whaling industry by both Greenpeace and the international community has reduced the fleet to sneaking out of port in a fog of crisis and scandal, desperate to avoid attention," Ms Holden said.

Greenpeace will not send out a ship to trail the Japanese fleet, but rival conservation group Sea Shepherd plans to.

The federal government sent out a ship last season, but has not said if it will do so this season. The government has announced it will spend $6 million on non lethal whale research to show the Japanese you don't have to kill whales to study them.

Japanese officials insisted there would be no changes to their hunting plans despite international protests and slumping demand for whale meat at home, news agencies reported.

Officials said no departure ceremony was planned for this year's expedition.

"We've decided not to hold a departure ceremony or announce the departure for safety reasons," said Fisheries Agency official Toshinori Uoya. Last year, he said, an environmental group tried to ambush the fleet just off the coast and the whalers narrowly escaped.

Japan kills about 1,200 whales a year in two hunting expeditions under a scientific program that Tokyo says provides crucial data on populations, feeding habits and distribution of the mammals in the seas near Antarctica and the north Pacific Ocean.

Japan's research hunts are allowed by the International Whaling Commission, but opponents call them a cover for commercial whaling that was banned in 1986.

Last year, a Japanese whaling ship and a ship owned by the animal rights group Sea Shepherd collided twice in Antarctic waters near a pod of whales.

The group's activists also dumped a foul smelling acid on another whaling boat, slightly injuring two crew members. Japanese police are conducting a criminal investigation in the case.

Because of the disruption, the fleet last year returned with 551 minke whales, just more than half of the planned catch.

Sea Shepherd has said that it also plans to try to disrupt Japan's 2008 09 whaling season in the Antarctic.

Japanese have hunted whales for centuries, and whale meat was widely eaten in the lean years after World War II. However, it has plunged in popularity in today's prosperous Japan. While still on the menu in a few upscale Tokyo restaurants, its consumption is largely limited to small coastal communities