Although it is conducted in the name of research, Japan's hunt provides supermarkets and upscale restaurants with the leftover whale meat.
Critics therefore charge that the country's whaling under the research exemption is just commercial whaling in disguise and demand it be stopped.
Sir Geoffrey Palmer, New Zealand's representative to the International Whaling Commission (IWC), last month called scientific whaling a "blank check."
"Any government can engage in it and can take an unlimited number of whales. That makes an absurdity of the whole treaty," he told National Geographic News.
The program has come under increasing international pressure in recent years as Japan has expanded its catch.
For example, this season the fleet had planned to kill 50 endangered humpback whales in the Antarctic for the first time in decades. Japan abandoned that plan last December in the face of protests by the United States and other governments.
And despite reported efforts to recruit poorer nations to back its position in the IWC, Japan has so far failed to win enough votes to have the commission strike down the commercial whaling ban.
Japan has long argued that the whaling ban should only apply to endangered species.
It also accuses the West of hypocrisy for criticizing current Japanese whaling after American and European whalers nearly wiped out the marine mammals in the 19th and 20th centuries.
The Japanese have a long history hunting whales, and whale meat was widely eaten in the lean years after World War II.
The meat has plunged in popularity in today's prosperous Japan and is only eaten regularly in some small coastal communities.
After a special IWC meeting last month, New Zealand's Palmer had hinted that Japan may be ready to deal, giving up whaling in the Southern Hemisphere in exchange for limited hunts near these coastal regions.
