National Parks and Wildlife (NPWS) spokeswoman Sarah Scroope said three rescue vessels were on the water off Narooma monitoring the calf and its mother.

A large NPWS vessel, Shearwater, based in Narooma, and specialist crews from Ulladulla and Merimbula in rubber duck crafts were keeping a close eye on the mammals.

The crews will assess the situation and determine if it is safe to cut the calf free, she said.

It depends on the weather and the behavior of the mother.

They hope to free the whale today (Tuesday).

The tangled whale was first reported off Depot Beach, in the Murramarang National Park, shortly after noon on Monday by a helicopter crew.

Floating buoys would be attached to the whale calf to prevent it diving, before crews attempted to cut it free.

National Parks and Wildlife Service team leader Lawrence Orel has overseen similar rescue efforts elsewhere.

We are keen to assist the animal, but the safety of everyone is paramount, Mr Orel said.

It cant happen until both animals are calm enough.

Once the mother is calm, crews in rubber boats will use cutting hooks to free the whale calf.

We are going to need to pay attention to the mother as they can be protective, he said.

The NPWS identified the tangled whale as a juvenile humpback, probably born in winter in Queenland and now migrating back to Antarctica.