The pod of 11 killer whales trapped in the Hudson Bay's ice last week may have been confused by the effects of climate change, researchers said.

This was the first time a pod of killer whales was found locked in by the frozen bay, said Petah Inukpuk, mayor of Inukjuak, an Inuit village in Quebec close to where the whales were trapped. The whales, which took turns breathing out of a small hole in the ice, were able to escape Wednesday night or Thursday morning as currents broke a path in the ice, Inukpuk said.

The Hudson Bay typically freezes over in late November or early December, so killer whales are usually found in the Hudson Strait or the North Atlantic at this time of year, said Lyne Morissette, a marine researcher with the St. Lawrence Global Observatory in Quebec.

"If food changes and temperatures are changing in the Arctic, they don't have the same kind of sensors or indicators that it's time for them to leave," Morissette said. "In this case, with climate change, we know that the whole environment is changing quite a lot, so it might be because their sensors or the things that indicate to them that it is time to do a certain part of their life cycle is not tuned to their biology right now because everything is changing so fast."

She said it's "definitely a direct effect, a good example of what climate change can do" (Miranda Leitsinger, NBC News, Jan. 11). -- EH