All but one of the 10 whales that survived a mass beaching on Australia's west coast were Wednesday believed to have come back ashore and were unlikely to survive, authorities said.
Rescuers used trucks and cranes fitted with giant slings to move 11 long-finned pilot whales by road to sheltered waters for release, after they beached with about 80 others on Monday at Hamelin Bay, south of Perth city.
One of those moved was put to death by specialists after straggling in poor health near to shore, and an aerial patrol spotted nine others again stranded along an impassable coastal area Wednesday.
"As well as the six whales east of Augusta three other whales have been sighted stranded in the Hamelin Bay area," said the environment department's Jason Foster.
"One has been attacked by sharks," he told Australian Associated Press.
Two of the whales were already dead and the rest were in such poor condition they would need to be put down, he said.
"The location is along a rugged stretch of coastline and it is impossible to bring in the machinery necessary to attempt a further rescue," he added.
Four-wheel drive motorcycles would have to be used to access the site, with no safe place for a helicopter to land, he said.
Tests and measurements would be done to confirm the whales came from the beached pod, before they were put to death by wildlife officers.
The latest beaching takes the total number of whales stranded around southern Australia and Tasmania in the past four months to more than 400.
Earlier this month rescuers saved 54 pilot whales after nearly 200 of the giant creatures beached themselves on King Island off Australia's southern coast.
In November, more than 150 pilot whales died after beaching themselves on Tasmania's west coast and in January, 48 sperm whales died on a sandbar at the north of the island.
The phenomenon of whale strandings and the causes remain the subject of scientific debate.
(c) 2009 AFP
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