All but five of more than 150 whales that were stranded on a beach in Western Australia have died. Volunteers spent a day trying to push the short-finned pilot whales back out to sea.
A desperate battle to save 150 whales washed up on a beach in Hamelin Bay, 315 kilometers (198 miles) south of Perth, has ended with just five of the pod having survived, officials said on Saturday.
Almost all of the mostly short-finned pilot whales had already died by the time the alarm was raised. A rescue operation was mounted to save some 15 living cetaceans still stranded in shallow waters. But only a handful were successfully returned to freedom.
One of the six re-stranded itself and was euthanized, Western Australia's Department of Biodiversity, Conservation & Attractions said on Twitter.
Workers used heavy machinery to lift several whales off the sand before carrying them to another part of the beach to release them. Swimmers then guided the surviving whales back to deep water.
Rescue efforts were hampered by dead whales in the water, rocky terrain and rough seas.
Spotted by fisherman
The whales were first discovered by a fisherman who alerted local authorities on Friday,
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Fears that the dead whales could attract sharks led officials to close several beaches in the vicinity.
"It is possible the dead and dying animals will act as an attractant, which could lead to sharks coming close in to shore along this stretch of coast," a Shark Smart alert said.
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Department of Biodiversity, Conservation and Attractions incident controller Jeremy Chick said the safety of the surviving whales was the priority. He warned that they could attempt to beach themselves at another location.
A tendency to strand
Adult short-finned pilot whales are about 5 meters (16.4 feet) long and weigh up to three tons. They are found in most waters around the world and generally travel in groups of less than 100.
In 2009, more than 80 pilot whales and dolphins died in a mass stranding at Hamelin Bay.
Scientists do not know exactly what causes whales to beach themselves, but short-finned pilot whales are known to be prolific mass-stranders.
The largest stranding of whales ever recorded in New Zealand, and possibly the world, involved an estimated 1,000 pilot whales on the shore of Chatham Island in 1918.
It is thought that the species, which typically dwell in areas that are topographically "steep," struggle with shallow, sloping underwater environments.
mm/sms (dpa, ABC, DBCA, Reuters)