Cape Town - Some of the pilot whales that beached at Noordhoek Beach on Sunday morning will be put to death, the National Sea Rescue Institute said.
“Seven are in poor health. We are still trying our best to save them but those that can't be saved will be humanely euthanased,” said NSRI spokesman Craig Lambinon.
Six of the 19 stranded whales had already died.
One whale was currently being transported to a naval base in Simonstown and will be taken out to sea.
“At this stage the first whale is on its way on a trailer to the naval base...There are a remaining five whales in good health and we are going to attempt to do the same for them,” said Lambinon.
He stressed that the priority for Sunday was a rescue operation.
The disposal of the carcasses would take place at a later stage, said Lambinon.
“That is not our priority at this time.”
Earlier, police, sea rescue and other services were on scene trying to hose down the surviving whales. The beach has been closed.
Residents were urged to stay away from the beach.
Marine biologists have said they do not fully understand why whales beach but there are many theories.
KwaZulu-Natal Sharks Board head of operations Mike Anderson-Reade said one of the theories was that when one of the leaders of the pod got caught in shallow water, so did the others.
“And then they get disorientated and find their way to shore,” he said.
Another theory is that when one of the lead whales gets ill, it beaches and the others follow.
“But these are all just theories, the reason is still unknown.”
Scientific American on its website said some environmental activists had suggested that mass strandings of dolphins, whales, and other marine mammals were as a result of human impacts of pollution, shipping noise and, in some cases, military sonar.
The beaching of the pilot whales was possibly the first-ever mass stranding of these creatures on the South African coast.
“I don't think we've had a mass stranding of pilot whales before,” said a marine life expert, who declined to be named for professional reasons.
Pilot whales are a type of toothed whale and there are two species Äshort finned and long finned.
“It's possible these are long-finned pilot whales, which are more prevalent in the southern hemisphere.”
The biggest killer of stranded whales was stress.
“Pilot whales are very sensitive to stress and will need to be released in calm waters,” the expert said.
Pilot whales were believed to be notorious for stranding themselves on beaches. The phenomenon is more common along the Australian and New Zealand coastlines.
Long-finned pilot whales can reach over six metres in length, and can weigh more than two tons.
The department of environmental affairs' oceans and coast branch, which co-ordinates the rescue of stranded whales and dolphins, was not immediately available for comment.
In 2009, 55 killer whales beached on Kommetjie Long Beach in Cape Town.
Hundreds of volunteers and rescue-workers joined forces and saved about a dozen whales. The others were shot. - Sapa