Last year, the International Court of Justice (ICJ) ruled that Japan's whaling in the Southern Ocean should stop, and an International Whaling Commission (IWC) panel said in April that Japan had yet to demonstrate a need for "lethal sampling" as part of scientific research.

However, Tokyo, which vowed at the time to resume its "scientific whaling" program starting with the 2015/2016 season, retooled its hunt plan to cut the number of minke whales it intends to take to 333, down by two-thirds from previous hunts.

Japan has long maintained that most whale species are not endangered and that eating whale is part of its traditional food culture. Making use of a loophole in international whaling regulations, it began what it calls "scientific whaling" in 1987, a year after a global whaling moratorium took effect.

'A happy day'

"Last year, regrettably, the ICJ made its ruling and we were unable to take whales," said Tomoaki Nakao, the mayor of the western city of Shimonoseki, which is both home to much of Japan's whaling fleet and part of Prime Minister Shinzo Abe's election district.

"There's nothing as happy as this day," he told the fleet's crew at a ceremony prior to their departure.

The ships set sail shortly before noon, with family members and officials waving from shore. The hunt is expected to last until March.

Conservationists' anger

Australia and New Zealand have led criticism of the resumption of Japan's whaling operations, with both expressing disappointment.

"It's not scientific research, it's straight up commercial whaling, and it's been declared illegal by the International Court of Justice," said Nathaniel Pelle from Greenpeace Australia.

Environmentalists from Sea Shepherd Australia, a conservation organization dedicated to protecting marine wildlife and habitats, have said they will pursue the Japanese fleet and will attempt to intervene in any slaughter of the animals.

av/tj (AFP, Reuters)