While few Japanese these days actually eat whale, criticism of the whale hunts has long been resented here as a form of Western cultural imperialism. During the long tenure of the Liberal Democratic Party, whaling was one of the sacred cows of Japanese politics, embraced by a group of nationalist lawmakers within the party who saw it as a rare issue where Tokyo could appeal to conservatives by waving the flag and saying no to Washington.

The question now is whether Mr. Hatoyama’s Democratic Party of Japan, which swept aside the Liberal Democratic Party in last summer’s elections, will include whaling in its promised housecleaning of Japan’s postwar order. While there is also a group of pro-whaling lawmakers in the new governing party, it is much smaller, with just a few active members.

However, the leader of the group, Tadamasa Kodaira, said in an interview that the Democratic Party was firmly committed to research whaling. Last summer, the party’s election platform included promises to seek a resumption of commercial whaling, though it did not specifically mention the government-run research program.

In an interview, Mr. Kodaira said he recognized that Japan’s whaling industry had shrunk to just a few hundred jobs, mostly paid for by the government. However, he said that the recent aggressive actions of foreign environmental groups like the Sea Shepherd Conservation Society, which has clashed with Japanese whaling ships near the Antarctic, had fanned popular ire, making it impossible for Tokyo to compromise now.

“We can’t change now because it would look like giving in,” said Mr. Kodaira, a lawmaker from the northern island of Hokkaido. “Will we have to give up tuna next?”

So far, the Democratic Party has left the program untouched. In November, Japan’s whaling fleet left for the Antarctic as scheduled, returning this month with a catch of 507 minke and fin whales, well below the planned take of up to 985 whales, according to the Ministry of Agriculture, Forestry and Fisheries. The ministry blamed the shortfall on the Sea Shepherd society’s obstructions.

Officials said that one reason the program remained hard to cut was that its budget was so small: only $86 million, of which only $17 million is paid for by the government in cash or zero-interest loans, according to a freelance journalist, Junko Sakuma, who has written extensively about whaling. The rest comes from the sale of whale meat, mostly that of the nonendangered minke whales.