Rescuers raced against the tide on Wednesday (September 23) off the Australian island of Tasmania, to try and save some of the estimated 470 whales stranded in a sandbank.
That's hundreds more than rescuers first spotted earlier this week, making it a record event.
Tuesday saw a mammoth of over 60 workers and volunteers trying to refloat and free the animals.
Twenty-five were freed, but officials say some beached themselves again, drawn back to shore by the tide.
Government marine biologist Kris Carlyon, gave an update on the resuce mission:
"We are not at a stage where we are considering euthanasia at this stage, the animals that are still alive we think we do have a chance with those given that they are wet, they are cool at this stage and we are pushing ahead."
The pod of long-finned pilot whales were first spotted by air on Monday. The stranded pod were believed to be about half the size, but then late Tuesday, more whales were spotted.
Nic Deka is regional manager of Tasmania's Parks and Wildlife Service: "They have detected around about another 200 in a couple of bays. Probably seven to ten kilometres away from the stranding that we have been working on."
Scientists do not know why whales beach themselves.
But they say when the animals travel in pods, they're known to follow a leader, and gather around one that is injured or in distress.