A pod of whales stranded on a WA beach have had to be euthanised after efforts to lead the mammals back into deeper waters failed.

Fifty-two whales initially died during a mass stranding event on Cheynes Beach, 60 kilometres east of Albany in the state’s south, on Wednesday.

Later volunteers and wildlife agency staff tried to guide the remaining 45 whales further away from the shore but they kept returning to the beach shallows.

“Sadly, the decision had to be made to euthanise the remaining whales to avoid prolonging their suffering,” WA Parks and Wildlife said on Wednesday night.

“It was a difficult decision for all involved however the welfare of the whales had to take precedence.”

The agency thanked everyone – including hundreds of volunteers with small vessels and surf skis – who had helped with the attempt to save the whales over the past two days.


Earlier on Wednesday, some of the whales guided back out into deeper waters re-stranded further along the beach where veterinarians began assessing their condition.

The pod of 97 long-finned pilot whales was spotted swimming perilously close to Cheynes Beach on Tuesday afternoon before a number began beaching themselves.

Wildlife experts speculated the unusual behaviour could be an indicator of stress or illness within the pod.

Macquarie University wildlife scientist Vanessa Pirotta said the reason the whales stranded themselves was a mystery.

“The fact they were in one area, very huddled and doing really interesting behaviours and looking around at times suggests something else is going on that we just don’t know,” she told AAP.

A whale might have been sick or the pod might have become disorientated but it was unlikely they were trying to avoid predators, Dr Pirotta said.

Pilot whales are highly social animals and maintain complex familial relationships with their pods from birth.