A Japanese whaling fleet sailing toward waters off Antarctica to kill protected humpback whales was itself the target of a hunt Monday by environmental activists who vowed to disrupt the expedition.
Greenpeace said its protest ship Esperanza was searching for the fleet south of Japanese territorial waters and would shadow the ships to the South Pacific to try to reduce their catch.
"It's a large ocean, but we're going to track them down," expedition member Dave Walsh told The Associated Press by telephone Monday.
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The Japanese fleet was embarking on the country's largest whaling expedition, targeting protected humpbacks for the first time since the 1960s.
In a farewell ceremony Sunday for the four-ship expedition, officials told a crowd at the southern Japanese port of Shimonoseki that Japan should preserve its whale-eating culture.
"They're violent environmental terrorists," mission leader Hajime Ishikawa said. "Their violence is unforgivable ... We must fight against their hypocrisy and lies."
Families waved little flags emblazoned with smiling whales and the crew raised a toast with cans of beer, while a brass band played "Popeye the Sailor Man."
The whalers plan to kill up to 50 humpbacks in what is believed to be the first large-scale hunt for the once nearly extinct species since a 1963 moratorium in the Southern Pacific put the giant marine mammals under international protection.
The mission also aims to take as many as 935 minke whales and up to 50 fin whales in what Japan's Fisheries Agency says is its largest-ever scientific whale hunt. The expedition lasts through April.
Japan says it needs to kill the animals in order to conduct research on their reproductive and feeding patterns.
While scientific whale hunts are allowed by the International Whaling Commission, or IWC, critics say Japan is simply using science as a cover for commercial whaling.
Ken Findlay, a whale biologist at the University of Cape Town in South Africa, said the humpback population was recovering but said he was worried Japan would kill whales from vulnerable breeding grounds like those off New Zealand.
He also said Japan's hunting methods were unnecessarily cruel. Japanese whalers sometimes chase wounded animals for hours, he said.
"I don't think firing a harpoon at a whale and then dragging it next to the ship is ethical," Findlay said. "You question the necessity of that. It's not research."
An IWC moratorium on commercial whaling took effect in 1986, but Japan — where coastal villages have hunted whales for hundreds of years — has killed almost 10,500 mostly minke and Brydes whales under research permits since then.
Tokyo has argued unsuccessfully for years for the IWC to overturn the moratorium.
The Japanese hunt, which puts meat from the whales on the commercial market, is growing rapidly despite an increasingly vocal anti-whaling movement.
This winter season's target of up to 1,035 whales is more than double the number the country hunted a decade ago.
Japan argues that it should have the right to hunt whales as long as they are not in danger of extinction.
The American Cetacean Society estimates the humpback population has recovered to about 30,000-40,000 — about a third of the number before modern whaling.
The species is listed as "vulnerable" by the World Conservation Union.