Drone footage taken on Feb. 6 off the coast of Rausu, Hokkaido, shows at least 10 orcas trapped by drift ice, trying to keep their heads above the water to breathe. (Provided by Wildlife Pro LLC. and Shiretoko Nature Cruise)

RAUSU, Hokkaido--Town officials on Feb. 7 lost sight of about 10 killer whales that were spotted the previous day struggling to breathe as drift ice closed in around them just off the coast here.

Rausu municipal officials said that they could no longer spot the orcas when they searched the area with binoculars from the shore for two hours in the morning.

An official said he hopes that the killer whales have managed to escape.  

Drone footage taken on Feb. 6 shows the orcas crowded together, surfacing their heads above the water to breathe through a small gap in the ice.

According to Shiretoko Nature Cruise, a whale-and-birdwatching tour operator, the stranded killer whales are likely part of a pod of about 20 that had been migrating through the Nemuro Strait for several days.

Rescuing the trapped animals is extremely challenging due to the inaccessibility of the site, which is blanketed by the thick ice.

“The area is covered in thick drift ice and it doesn’t seem like they have anywhere to escape to,” said a tour employee. “But they are wild animals, so I hope they managed to find a way out somehow.”

Although there were still gaps in the drift ice early that morning, the ice grew quickly to cover the entire sea surface, forcing all but the first cruise that day to be canceled.

After receiving a report about trapped orcas, the tour employee drove to the coast and spotted the mammals about 1 kilometer off the shore.

She confirmed with binoculars that the black and white heads of the killer whales were “popping out” from small gaps in the ice as they exhaled spouts of air and water.

The orcas remained stuck at that spot while she observed them from 8:30 a.m. to 10 a.m.