A small Japanese fleet caught whales on Monday in their country's first commercial hunt in more than three decades, sparking global condemnation and fears for the fate of the giant mammals.
Japan has long claimed that few whale species are endangered.
It announced in December that it was leaving the International Whaling Commission to resume hunting after years of campaigns by industry supporters and Prime Minister Shinzo Abe, whose constituency includes a city with a long tradition in the business.
"If we had more whale available we'd eat it more," said Sachiko Sakai, 66, a taxi driver on the northernmost main island of Hokkaido, where five whaling ships were waved out of the harbour in a brief ceremony.
Ms Sakai said she ate a lot of whale as a child.
"It's part of Japan's food culture. The world opposes killing whales, but you can say the same thing about many of the animals bred on land and killed for food."
The ships, which are set to be joined by vessels from the southern port of Shimonoseki, will spend much of the summer hunting for minke and Baird's beaked whales.
Crew in orange life vests took positions on the decks as the blue-hulled ships sailed out of Hokkaido's Kushiro port, some with red banners fluttering from their masts.
By Monday afternoon, one ship returned with an eight-metre minke whale. It was winched up from the vessel and taken off to be weighed and butchered.
"This is a great day. I'm really happy with the resumption of commercial whaling," said Yoshifumi Kai, head of the Japan Small-type Whaling Association. "We were able to take a splendid whale."
Japan began whaling for scientific research a year after a 1986 ban on commercial whaling, aiming to gather what it called crucial population data, but it abandoned commercial whaling in 1988.
Critics said the programme was simply commercial whaling in disguise, after the meat of animals taken in scientific whaling ended up in restaurants.
This year's quota for commercial whaling, including minkes, sei and Bryde's whales, is 227, the Fisheries Agency said.
The quota, to be set annually, is fewer than the 330 whales Japan caught in the Antarctic until recently.
"We're not at all embarrassed by what we do, it's only natural," Mr Kai said. He claimed that the amount of whales Japan planned to hunt would not pose a threat to their population.
Environmentalists said the launch was delayed until after the G20 Summit hosted by Japan but whaling proponents denied this.
"This is a sad day for whale protection globally," said Nicola Beynon of the Humane Society International.
"The word 'research' may have been removed from the side of the factory ship, finally ending Japan's charade of harpooning whales under the guise of science, but these magnificent creatures will still be slaughtered for no legitimate reason."
Whaling is a tiny business in Japan. Whale makes up about 0.1 per cent of all meat eaten in a year, with about 300 people directly linked to the industry.
Japan's annual supplies of about 4,000 tonnes to 5,000 tonnes amount to 40 to 50 grams for each citizen, or about the weight of half an apple. Even whaling supporters say building demand will take time.
Patrick Ramage, head of the International Fund for Animal Welfare, called the move a face-saving solution that could eventually lead Japan to abandon whaling.
"It's a good decision for whales, it's a good decision for Japan, and it's a good decision for international marine conservation," Mr Ramage said.