We are still far from understanding why whales strand despite the fact that it may seemingly be becoming more prevalent. It's unclear as to what triggers such events, but there are several theories.

We do know that whales can come unstuck on long, gradual, sloping seabeds where a navigational error suddenly puts them in shallow water.

Pilot whales strand more than any other whale species. But their huddling together was a very rare, unusual behaviour before the stranding event.

Pilot whales are extremely socially gregarious animals and are tightly knit in terms of social network. They often move in familial groups and try to stick together and help each other out if something is wrong - they tend not to leave individuals to their own fate, so one theory is that they may have been protecting a sick individual.

Or it could have been protectionist behaviour with the whales sheltering from a predator, namely orca. Although we can’t rule it out, I would have expected there to have been reports of orca sightings in the area if that was the case.

Another theory is that the huddling and then stranding were a response to sonar noises from deep water vessels, but being where these whales were in shallow coastal waters, it would be highly unlikely those noises could have reached them.

Time is running out for the whales that are still alive, it is critical they get back out to sea within 24 hours although within 12 hours is optimal.

Whales evolved to live in the water, they are massive animals, with long-finned pilot whales weighing up to 2.5 tonnes each, and without buoyancy, basically their internal organs are being crushed. Even if you get them back out, they may still suffer internal organ failure and die.

It’s possible to save them, but it will be difficult. They have to get through the breakers and there is also the risk of re-beaching which is quite common. With pilot whales having such close social bonds, they might not want to leave the others on the beach.