Euthanised whale removed from NSW beach

A juvenile humpback whale that became beached on the NSW mid north coast has been removed for scientific sampling.

The nine-metre whale was first spotted by beachgoers at Sawtell Beach, south of Coffs Harbour, early on Friday but rough sea conditions over the past two days hindered rescue attempts.

The whale's health deteriorated as the hours passed and the young whale, weighing about 10 tonnes, was put down about 1pm on Saturday, marine rescue organisation Orcca vice president Shona Lorigan said.

"It's been taken away for scientific sampling - a necropsy," she told AAP on Sunday.

Saturday's decision to euthanise the animal was difficult, she said, but rescuers considered the whale's welfare and did not want it to suffer any longer.

The weather had not helped the situation with big waves and rough conditions delaying rescue boats until at least Monday, Ms Lorigan said.

The yearling whale was likely making its first migration from Antarctica to Queensland after being weaned, she said.

The whale was taken off the Sawtell Beach by the local council on Saturday afternoon and the beach has been cleaned, a National Parks and Wildlife Service spokeswoman told AAP on Sunday.