The short-finned pilot whale is a large species of dolphin with a dark-grey body and a bulbous head. It’s an intensely social animal that spends its life in the company of others. And that, sadly, is also how it sometimes dies.
On Thursday night, around 150 short-finned pilot whales stranded themselves at Hamelin Bay, a site on Australia’s western coast around 200 miles south of Perth. If they land on solid surfaces, their chest walls, no longer supported by the weight of the water, start to compress their internal organs. When a fisherman spotted them in the early hours of Friday morning, most were already dead. By 7 p.m. local time, trained staff and volunteers had hauled six survivors back into the sea, but their fate is still uncertain. Rescued whales often re-strand themselves, and nightfall will make their movements harder to track.
Western Australia is no stranger to mass whale strandings. Nine years ago, to the day, 80 long-finned pilot whales—a closely related species—stranded themselves in the very same spot. Three years ago, again almost to the day, around 20 long-finned pilot whales washed up at Bunbury, about 70 miles to the north. And those incidents pale in comparison to the largest mass stranding ever documented in the region. In the summer of 1996, 320 long-finned pilot whales beached themselves at Dunsborough, less than 50 miles to the north.
This isn’t a uniquely Australian problem. New Zealand’s Farewell Spit is a notorious whale trap where pilot whales regularly strand; up to 650 long-finned pilot whales beached there last February, of which 400 or so were saved. Cape Cod is another hot spot, and sees an average of 226 stranded whales and dolphins every year. Pilot whales seem especially susceptible, but even larger species will beach themselves. Over 300 sei whales died at a Chilean fjord in 2015, while 29 sperm whales washed up on the coasts of the southern North Sea in 2016.