Opposition by anti-whaling nations will not stop Japan from pressing ahead with its upcoming hunt, which will take humpbacks for the first time in 40 years.

The hunt, which is now under way, has drawn criticism from Canada, the United States, Australia, New Zealand and the European Union.

Japan’s hunt is conducted by a government-backed research institute to collect scientific data on whale demographics that Tokyo needs to build a case for the lifting of a global commercial whaling ban. Critics, however, say the program is commercial whaling in disguise, because the meat is sold after the data is collected.

A Japanese whaling fleet left the port of Shimonoseki in southern Japan last week for the Antarctic, where the crews hoped to kill as many as 50 humpback and 50 fin whales, plus 935 minke whales -- Japan’s largest-ever scientific whale hunt.

Here are two perspectives on Japan’s continuing practice of hunting the extraordinary marine mammals.

After two decades of scientific whaling, Japan should be a leading authority on whale biology.

No other country in history has ever killed and cut up as many whales for the sake of research.

But the more science that Japan does on whales, the more other scientists see evidence that it is a sham.

After 7000 minkes were killed in the first Japanese Antarctic Research Program (JARPA), it was reviewed by the International Whaling Commission’s scientific committee.

The review by the best whale scientists from 31 countries found the program could have improved the management of minke whales in the Southern Ocean.

But this outcome was not realised. Instead, despite the toll in whales, the review found its objectives were largely unachieved.

Now that JARPA II has escalated the whaling effort by moving into two threatened species, fin and humpback whales, it faces the same problem, according to whaling commission scientists led by Australia’s Nick Gales.

“A lethal research program that targets low priority science, with a demonstrably low likelihood of achieving its stated objectives, appears unsupportable when viewed in a scientific context,” Dr Gales wrote this month in the journal Nature.

“It is time to acknowledge that the debate about research whaling has little or nothing to do with science,” Gales said.

One of whaling’s fiercest critics ranks of Japan’s own scientific fraternity. Toshio Kasuya, a retired professor who worked for the Fisheries Agency’s whaling program in the 1980s, launched a scathing attack on his former colleagues in the national Mainichi Shimbun two years ago.

“Without the earnings from the meat sales, the whaling organisation that undertakes the Government-commissioned research program would be unable to continue operation, and the shipping company that provides the fleet for the program would not be able to recover costs for whaling vessel construction,” he wrote in an opinion piece.

“This is nothing other than an economic activity. It leaves no room for researchers to carry out research based on their own ideas. It certainly does not conform to the scientific purpose authorised by the [International] Convention [for the Regulation of Whaling].”