Scientists have made a significant discovery regarding how baleen whales produce sounds underwater. Whales, the largest mammals to have ever lived, emit sounds that travel through the ocean, but the mechanics behind their vocalizations have always been a mystery.
all freely swimming now. reporter: the frustrating park is the whales keep circling back. if the whales can t or won t make their way back into deeper water, rescuers say it s only a matter of time before they go into stress and their bodies begin to shut down. at that point they have to be euthanized. reporter: some are already exhibiting signs of distress. how much longer they can survive, no one is sure. the rescuers will remain out there until they re saved or all hope is gone. now, the dilemma, of course, is these whale pods are like families. they are families. when some of them are in distress, stranded on the beach and die like those have already done, these other whales that are out there are very, very reluctant to leave. chris, kate? as you said, exhausted all the same. thank you so much, john, for the update. it s horrible to see them there. there s not much they can do. they ll keep trying. you get lucky. sometimes they find their own