Three crews had been monitoring the entangled calf, who was traveling south with its mother, since it was sighted by a helicopter crew off Depot Beach at noon on Monday.

National Parks and Wildlife spokeswoman Sarah Scroope said the calf was cut free from 90 per cent the rope between 5pm and 6pm on Tuesday.

It is now free and swimming with its mum, she said.

Crews are now returning to shore and will reassess the whale in the morning.

Ms Scroope said it was getting too dangerous to get the remaining bit of rope removed from the calf.

The calf and the mother were still happy but the calf was beginning to show signs of becoming distressed, she said.

The rest of the rope is through its mouth and wrapped around its head.

In this case, that was the hardest bit to free.