TOKYO, April 10 -- Four Japanese whaling ships set sail from a port in the country's northeast on Friday aiming to hunt up to 51 minke whales in a 90-kilometer radius from Ayukawa port in Ishinomaki, Miyagi Prefecture, under what Japan describes as a "scientific research" whaling program.

According to the Association for Community-Based Whaling, the mission to hunt whales in the northwestern Pacific Ocean is to examine the effects of the whales on other marine life by checking the contents of the whale's stomachs and other such "scientific" examinations.

Despite the International Court of Justice ruling that Japan's research whaling in the Antarctic Ocean is in violation of the International Convention for the Regulation of Whaling, and ordering Japan to stop its whaling program, Japan has only gone as far as scaling down its activities in the Antarctic and the Pacific, and continues to maintain its whaling is for scientific purposes and not for commerce.

Commercial whaling was banned in 1986 by the International Whaling Commission (IWC) and most former whaling nations followed the ruling with the exception of Iceland and Norway, who have lodged official objections to the ban and continue to hunt commercially, and Japan, who activists claim are hunting commercially and are exploiting the scientific research permit as a loophole.

Prior to the ships setting sail Friday, Yoshiichi Shimomichi, head of the Association for Community-Based Whaling, said he hopes the operation will be a success and the results will help to prove that the numbers of whales are sufficient for Japan to resume its commercial whaling operations in the future.

Japan plans to kill 333 minke whales a year over the next 12 years, despite the ruling, a number believed by conservationists to still be far more than necessary for just research purposes, with the only rationale being that Japan is still hunting whales for commercial reasons.

But Japan's whaling operations, scientific or otherwise, have hit a number of obstacles of late, and while their fleets successfully killed 251 minke whales in the 2013-2014 whaling season and 103 whales the previous year, for the first time in more than 30 years the whaling fleet returned from its yearly Antarctic trip in late March without a single whale.

Observers have suggested that the reason could have been due to diminishing numbers of minke whale, although pointed out that while numbers of the species are dropping and despite at least 13 great whales being officially listed as endangered, the minke is, as yet, not on the endangered species list.

Other issues denting Japan's operations include declining demand for whale meat, more so after conservation groups revealed that Norwegian exports of minke whale to Japan contained potentially harmful levels of toxic pesticides, making that meat unfit for human consumption.

Both the Environmental Investigation Agency (EIA) and the Animal Welfare Institute (AWI) presented evidence showing that Japan's government rejected imports of Norwegian whale meat, owing to tests showing levels of contamination that were more than double that of Japan's import safety standards.

Japan imports around 70 tons of minke whale meat per year, but despite a fondness for the meat by the older generations here, the meat has fallen out of favor with the younger generations, due to the whaling controversy and ever-increasing options for international cuisine.

"They catch the whales and allegedly experiment on them for science and then sell what's left of the meat to shops and restaurants," said Masayuki Kobayashi, 24, a graphic designer in Tokyo. "This is not appetizing at all, I'd rather eat regular sushi as least I know it's fresh," he said.

Similarly, Keiko Endo, a 21-year old art student said she had eaten whale as a child, but didn't come across it very much these days as it was becoming increasingly unpopular among her generation.

"It's got kind of an old image, I can imagine my grandparents eating it, but if I got a text from one of my friends saying, 'Hey, let's eat whale tonight!' I'd think they were joking," she said.

"I think whale used to be more popular in the past because it was cheap, but I don't really see it on sale so much these days, although I know there are restaurants even near here (Shibuya) that specialize in it. But I'd rather have regular Japanese or other Asian food, if I had the choice. If people aren't really eating whale, then Japan should stop hunting it. I think this is common sense," Endo said.