Another 20 surviving whales could potentially still be saved on Thursday and vets were considering euthanizing another four, officials said.

The discovery of 200 additional pilot whales three days into the rescue of 270 others makes it Australia's biggest beaching in modern times.

A rescue mission is underway to get the whales back into the water as the tide comes back in.

About 75 whales were already dead when a hiker discovered them on Stewart Island, and conservation workers decided to euthanize the others due to their poor condition and remote location.

Whale lovers in New Zealand finally got some good news on Sunday after more than 200 stranded whales managed to refloat themselves overnight and swim away, while volunteers managed to save another 17 whales at high tide.

The pilot whales swam aground at a remote beach.

About 275 of the pilot whales were already dead when people found them Friday

Two dozen pilot whales died after beaching themselves on the Baja California Peninsula despite efforts to move them into deeper waters, Mexico's navy said Sunday.

Another group of beached whales in Nova Scotia has been helped back out to sea, marking the second time this week that concerned residents joined together to save a stranded pod.

Authorities said eight pilot whales have died in shallow waters off Florida's southwest coast. Six others remain unaccounted for.