Rescuers are struggling to save more than a dozen whales and dolphins stranded on an Australian beach.

Most of the 80 washed ashore in Hamelin Bay, Western Australia are dead but volunteers and conservation officials are still trying to help the 17 survivors.

The state's Conservation Department said it planned to transport the few survivors to a protected bay before attempting to launch them back to sea.

The department said the group of whales and bottlenose dolphins became stranded on a stretch of beach about four miles long.

Department officers originally thought the mammals were false killer whales, but on closer inspection said they were long-finned pilot whales.

Strandings happen periodically in Tasmania, in the southeast, as whales pass during their migration to and from Antarctic waters, but scientists do not know why.

It is unusual, however, for whales and dolphins to become beached together.

Earlier this month, 194 pilot whales and seven dolphins became stranded on a sandbar in Tasmania and only 54 whales and five dolphins were able to be saved.

In January, 45 sperm whales died after becoming beached on a different Tasmanian sandbar.

Last November, 150 long-finned pilot whales died after beaching on a rocky coastline one week after a pod of 60 also came ashore on the island state. Only 11 were rescued.

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