Japan finished what it calls research whaling for the fiscal year 2018 in the northwest Pacific, catching 134 sei whales and 43 minke whales as planned, the Fisheries Agency said Wednesday.

The whaling program, started May 17, is aimed at helping calculate an appropriate number of catches and for research into the ecosystem by studying the stomach contents of whales and taking their skin, according to the agency.

Findings will be reported to the International Whaling Commission.

In observational research, 413 sei whales and 50 minke whales were spotted in the sea. Skin was taken from a total of nine whales, the agency said.

Japan's "research whaling" has been a target of international criticism as meat from the hunted animals is sold after the scientific examinations. Critics say it is a cover for commercial whaling.

Japan conducts whaling missions in the northwest Pacific and the Antarctic Ocean. The northwest Pacific program includes whaling in the Okhotsk coastal areas, mainly in the sea off Hokkaido, Japan's northern main island.