On December 27, four spotted seals that had been cared for at the Okhotsk Tokkari Center Seal Land in the city of Mombetsu in the Okhotsk region of eastern Hokkaido, were returned to the sea from Mombetsu Port. The seals have transmitters attached to their backs and, in addition to ecological research, the seals will also play a role in environmental research in the Sea of Okhotsk.

The installation of the transmitters is part of the research by Professor Ohshima Keiichiro and his colleagues at the Institute of Low Temperature Science, Hokkaido University. In the past, they have attached location information transmitters to seals and released them to study their migration routes.
　
The devices fitted this time will also be able to detect the temperature, salinity and depth of the water, and will also be used to explore the underwater environment, taking advantage of the fact that seals dive under the sea. The data that is collected will be monitored in almost real-time via satellite until spring, when the transmitters will be shed along with the seals’ fur.
　
In addition to the four injured and weak seals, Seal Land has been caring for 24 other wild seals. This is the first time in eight years that seals have been released back into the sea, and all of them are presumed to be about 8 or 9 months old, having been rescued from the Sea of Okhotsk in April and May of 2021.
　
The four seals were released on the boat landing ramp under the watchful eye of Professor Mitani Yoko – who, until October, worked at the Hokkaido University Field Science Center for Northern Biosphere – and members of the Kyoto University Wildlife Research Center. At first, the seals were reluctant to enter the sea after so long away, but the Seal Land staff encouraged them on their way as they looking back from time to time.
　
Okazaki Masako, the chief exhibit keeper at the Tokkari Center, looked a little sad as she saw them off. “I hope they grow up big and healthy,” she said.