The Ministry of Agriculture, Forestry and Fisheries said the Japanese fleet will be returning home soon, though it did not provide an exact timeline. The season usually runs from November or December to late February or early March.

Japan’s government announced on Friday it is ending this year’s Antarctic whale hunting season early due to repeated harassment from activists at sea.

The Ministry of Agriculture, Forestry and Fisheries said the Japanese fleet will be returning home soon, though it did not provide an exact timeline. The season usually runs from November or December to late February or early March.

The government blamed repeated harassment of its whalers by Sea Shepherd Conservation Society ships.

Sea Shepherd ships have been chasing the Japanese fleet for weeks in the icy seas, trying to prevent the whalers from filling their seasonal quota of 945 whales.

The conservation group has waged its campaign of physical intervention against the whalers for seven years. Its campaign has drawn high—profile donor support in the United States and elsewhere and spawned the popular Animal Planet series “Whale Wars.”

Protesters have thrown rancid butter in bottles toward the whaling ships. They also once got a rope entangled in the propeller on a harpoon vessel, causing it to slow down.

The whale hunts, which Japan says are for scientific purposes, are allowed by the International Whaling Commission as an exception to the 1986 ban on whaling, but opponents say they are a cover for commercial whaling because whale meat not used for study is sold for consumption in Japan.

Japan had temporarily halted the hunt on February 10 and said the suspension would last until conditions were deemed safe. But the government decided to call the ships back to ensure the safety of the Japanese crew amid the “confusion” caused by the attacks, said fisheries agency official Tatsuya Nakaoku.