Japan has caught 59 whales off the coast of the northern island of Hokkaido, officials said Monday, under a research program that critics say is a cover for commercial whaling.

The annual expedition off the port city of Kushiro ended over the weekend after harvesting 59 minke whales, the Fisheries Agency said in a statement. The catch was one whale short of the maximum 60 allowed under the research program authorized by the International Whaling Commission.

Japan and other pro-whaling nations have been pushing for the IWC to revoke the 1986 ban on commercial hunts amid arguments over the number of whales left in the world's oceans.

Japan also hunts about 1,000 whales in the Antarctic Ocean and the northwest Pacific Ocean under an IWC research program.

Critics say the expeditions are a cover for commercial whaling because the harvest is sold to market for consumption.

As in previous years, the Fisheries Agency said the hunt off Hokkaido was aimed at studying the whales' feeding patterns and their effect on fish stocks. Findings will be presented at next year's meeting of the IWC.

During the 12-day expedition, whalers caught 36 male whales and 23 females, the agency said. Examination of their stomach contents found that the minkes most commonly fed on pollack, krill and anchovy in the research area, about 80 kilometers (50 miles) off the coast of Kushiro in the Pacific Ocean, it said.

Kushiro is 895 kilometers (556 miles) northeast of Tokyo.