UPDATE: TWO pigmy sperm whales had to be euthanased after becoming stranded on Coffs Harbour's Gallows Beach on Sunday afternoon.
The mother and her calf were swept onto rocks in heavy surf.
The mother was estimated at four-metres in length, while the calf was said to be a newborn.
Onlookers Justin Motbey and Koby O'Brien swam out to assist the whales before alerting authorities.
National Parks & Wildlife workers, Pet Porpoise Pool staff and their assistants worked to stabilise the animals, as heavy rain and surf hit the coast.
National Parks and Wildlife Service spokesman Lawrence Orel said the effort to stabilise the whales was undertaken in the hope they could be returned to the ocean.
Mr Orel said due the mammal's worsening condition they were euthanased.
He said post mortems would be undertaken on the mammals to determine why they became stranded.
Pygmy sperm whales are common along the East Coast, but are rarely seen so close to shore.
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