More than 160 pilot whales stranded in Western Australia

More than 160 pilot whales became stranded off the coast of Western Australia on Thursday, local authorities said.

Western Australia's parks and wildlife authority DBCA said the whales became stranded in shallow waters near the small town of Dunsborough, some 250 kilometres south of Perth.

By midday, 26 animals had died, Australian broadcaster ABC quoted a DBCA spokeswoman as saying. Volunteers were feverishly trying to keep 140 more whales alive, the report said.

"Based on previous strandings involving this species of whale, such as at Cheynes Beach near Albany last year, these events usually result in the beached animals having to be euthanized as the most humane outcome," the Parks and Wildlife Service of the state of Western Australia said on Facebook.

Meanwhile, emergency services used boats to try to prevent another group of around 20 pilot whales from also getting stranded. A little further from the coast, another herd of around 110 whales was also found in deeper water.

Animal rights activists and local residents rushed to the beach to douse the 160 pilot whales with water to keep them alive. However, local authorities urged the public to only approach the whales under the guidance of experts.

"We know people want to help but we asked that people please do not attempt to rescue the animals without direction of DBCA staff as this may cause further injury, and distress to the animals and hinder a coordinated rescue effort," the authority said in a statement.

"The highest priority at mass whale stranding events is always human safety followed by animal welfare. We want all staff and volunteers to go home safe."

Marine expert Ian Wiese, who was at the scene, told Radio ABC Perth that several whales had already died.

"The others are just thrashing around and we'll have many deaths in the next few hours," Wiese said. "It's terrible... there's lots of theories around the world but nobody's really been able to find a cause."

The largest mass stranding in Australia was in the same area in 1996, when 320 long-finned pilot whales were beached. Almost all the animals survived.

In 2018, 100 pilot whales died in Hamelin Bay in Western Australia after another mass stranding.

Last year, almost 100 pilot whales became stranded on Cheynes Beach east of the city of Albany in the south of the state. Despite the best efforts of emergency services and volunteers, none of the animals survived.

Pilot whales form extremely close bonds with each other. At certain times of the year, they travel in large pods, which increases the risk of mass strandings.