The pod of 97 long-finned pilot whales gathered in shallow water off Cheynes Beach, about 400 kilometres (250 miles) southeast of Perth, on Tuesday, with scores stranding themselves on the sand.
Nearly 100 pilot whales have died after beaching in Western Australia, wildlife officials said Thursday, following desperate rescue attempts."Volunteers and everyone attempted to get them back out into the deeper water, and then they re-beached themselves," a spokeswoman for the Parks and Wildlife Service told AFP.
"From that point, the vets assessed them and it was determined on welfare grounds that they needed to be euthanised."