Mass stranding of pilot whales leaves experts puzzled
MARY LOUISE KELLY, HOST:
And now a sad story from Australia, where a pod of nearly a hundred pilot whales became stranded on a beach. Despite Herculean efforts by wildlife experts and volunteers to push the whales back into the water, dozens died, and after 24 hours, Western Australia's Parks and Wildlife Service announced the decision to euthanize those that remained to avoid prolonging their suffering. To find out why these whales that generally live in deep waters ended up stranded on a beach, we are joined by Andrew Read. He's a professor of marine biology at Duke University who studies pilot whales. Dr. Read, welcome.
ANDREW READ: Nice to be with you.
KELLY: Begin by giving us just the briefest of descriptions of pilot whales, how big they tend to be. And do they tend to stay together in big groups like this - dozens and dozens of them together?
READ: They do. They're extraordinarily social animals. They live in societies, much like elephant societies, that revolve around matriarchs. And family groups can range up to 20 or so. And so often you get multiple family groups together, as seems like was the case in Western Australia. And these are medium-sized whales. They're 15 to 20 feet long. But really, I think the most salient point is their really strong social bonds. So animals, females especially, that are born into a group will stay in that group for life. So when something happens to one individual, its groupmates will stay with it, even if it puts them at risk in cases like the one we saw here in Western Australia.
KELLY: Well, and there is video - this is drone video - of this particular pod shot right before they beached themselves doing something strange and quite beautiful. Would you describe it?
READ: Yes. In almost 20 years of studying pilot whales, I've never seen anything like it. The animals are, for want of a better word, kind of huddled together - a hundred whales in a very, very small, compact space, all touching, changing the orientation of the group. It's quite extraordinary video. And to be honest, we really don't understand what caused that behavior.
KELLY: Well, at one point, volunteers and Parks and Wildlife Service staff were able to move some of the whales from the beach back into deeper waters. And they came right back, beached themselves again hours later. Do we know why that behavior?
READ: No, but it's not uncommon. And, again, because of these really tight social bonds, if some of the relatives of the whales that were pushed off were still back on the beach and calling, it's not surprising that they came back to the beach. Remember; these animals spent their entire life at sea. They've never supported their weight on land before. And so as soon as the animals come to the beach, they start to undergo really incredible levels of physiological stress.
KELLY: I hear you saying we don't have a definitive answer as to why this particular pod behaved in the way it did. But what's your best guess, having studied them all these years?
READ: We've been talking about this in my lab for the last couple of days, and...
KELLY: I can imagine. Yeah.
READ: ...None of us has a definitive idea. It could be that there was some kind of external stimulus, a sound that the animals heard that terrified them, essentially. It could be that there was a sick individual in the middle of that group and the animals were concerned about its welfare. The scientists in Western Australia are conducting post-mortems on the animals now, and so we'll know whether any of the animals were sick. But we really are puzzled.
KELLY: I know on one level, you approach this as scientists, trying to gain information about a creature that you've spent your career studying. Is there a part of you as a human whose heart just breaks when you watch this?
READ: Absolutely. And I think anybody who's ever been on a beach in a mass stranding knows how heartbreaking it is. And you're holding animals up and trying to make sure that they know that somebody is there trying to look after them. You just get a sense for the strong emotional attachment that animals have with each other. And seeing these animals with really high cognitive function in such a terrible state on the beach is a really distressing thing to see.
KELLY: That is Andrew Read, director of the Duke University Marine Lab. Professor Read, thanks for speaking with us.
READ: My pleasure. Thank you, Mary Louise. Transcript provided by NPR, Copyright NPR.