A humpback whale is fighting for its life in Hickman's River, east of Cove Rock in East London in the Eastern Cape.
The 9.5 metre long mammal had been stranded in a tidal zone for almost half the day, said Kevin Cole, East London museum principal scientist.
Cole said his team is trying its best to get the whale back to sea but it has taken a lot of strain.
"It doesn't have any trauma on it and I don't see any visible scarring or anything like that. It seems to be in reasonable health. There is no discharging of any liquids or blood anywhere," he said.
Cole said the whale was stranded on a very shallow beach and unfortunately came up to the tidal area. Chances of it surviving are slim, he said.
"There is no way we can actually rescue the animal. We are waiting for the high tide to see if it will free itself.
"We have seen that its energy is very low because it has been lying here for a couple of hours and there will be a lot of strain on the internal organs, lungs and heart," he said.
The sex of the mammal has also not been established at this stage.
He said the rescue team would remain at the beach and monitor the whale.
"I don't think it's going to make it through the night. It's been too stressed by the situation of the stranding. It won't survive," he said.
Cole said he would return to take its blood, liver, lung, heart and bladder samples.
"If I can, I will see if I can get to the stomach tomorrow and see if there is anything in that part of the animal. That's the best we can do at the moment."