A lobster diver survives brief imprisonment inside the throat of a whale.

On Friday morning, a commercial lobster diver was caught in the throat of a humpback whale off the coast of Cape Cod, Massachusetts, and thought he was going to die.

After being released from Cape Cod Hospital, Michael Packard, 56, of Wellfleet, Mass., told that he was about 14 metres deep in the waters off Provincetown, Mass., when "all of a sudden I felt this enormous impact, and everything went dark."

He believed he'd been attacked by a shark, which is prevalent in the area's seas, but then discovered he couldn't feel any teeth and wasn't in any pain.

"Then I realised, oh my God, I'm in the jaws of a whale... and he's trying to swallow me," he explained. "And I thought to myself, OK, this is it — this is it — I'm finally — I'm going to die." His mind wandered to his wife and children. He believes he was in the whale's mouth for around 30 seconds, yet he continued to breathe because his breathing device was still in place.

The whale then came to the surface, shook its head, and spit him out. In the surface boat, he was rescued by a crewmate. According to Charles "Stormy" Mayo, a senior scientist and whale expert at the Center for Coastal Studies in Provincetown, such human-whale encounters are uncommon.

Humpbacks are not hostile, and Mayo believes the meeting happened by chance while the whale was feasting on fish, most likely sand lance.