Many volunteers did 20 minute stints in the water supporting the weakened whales to stop them from drowning.

National Parks and Wildlife Service urged sightseers to stay away and said it would call for volunteers on radio if more were needed.

The rescue operation to move 44 surviving whales from the pod of 49 - five died on the beach, began on the Monday afternoon.

Hundreds of volunteers spent hours pouring thousands of litres of seawater over the whales to keep them cool after they were discovered near the Sugar Loaf lighthouse just before 6.30am.

The high tide at 8pm on Monday threatened the whales, some up to four metres long, which were too weak to swim out to sea.

As the high tide approached, rescue teams pushed whales onto tarpaulins and heaved them further up the beach until they could be moved to the holding pen.

The whales were then lifted on to four-wheel-drive trucks and trailers and transferred across Treachery Headland to the holding pen at Boat Beach, where an underwater barrier made from tins on ropes was erected.

Fewer than a dozen whales were moved by late Monday night. It was not known what had caused the whales to strand themselves.

A ranger based at Myall Lakes National Park, Rosemary Black said once the whales were on the beach it was "virtually impossible for them to get back through the breakers."

One group pushed a whale back to sea but it beached itself again, too weak to make any advance through the surf.

Among the volunteers were Karen Selkirk and Steven Smith from Old Bar who had named the whale they and friends were caring for "Maybe".

"Maybe he will live, maybe he will die," Mr Smith said.

Miss Selkirk said they had heard a call for volunteers on a radio broadcast so they turned up wearing wetsuits and brought along brightly coloured beach towels to drape over the whales.

One group had even erected tree branches in the sand to shade a whale and an ambulance was moved into place to shade another.