A pod of 40 pilot whales has restranded on Farewell Spit, just hours after they were refloated by volunteers this morning.
Around 100 whales stranded at the Spit, on the northwest tip of the South Island, around midday yesterday.
Thirty-four whales died overnight, while 17 others freed themselves at high tide. The surviving whales were refloated by volunteers this morning.
But this afternoon, volunteers were again digging deep to restart emergency first aid as the animals returned to the beach.
"The tide dropped so quickly and there was a huge effort from volunteers to stop the animals restranding, but now they've grounded again," Project Jonah chief executive Kimberly Muncaster said.
"We'll be desperately trying to keep them alive until nightfall and we hope they may refloat themselves at high tide around 11.30pm."
Muncaster said when the whales were refloated, volunteers knew there was a chance they could end up back on the beach.
"We hoped it wouldn't be the case, but sadly these animals are finding it very hard to get back out to safe waters."
"This kind of restranding is not unusual for Golden Bay. Although the animals were refloated they didn't move quickly enough in the right direction."
The pod of 17 whales that refloated overnight continue to make their way out of the bay and were last reported to have about 28 metres of water beneath them, Muncaster said.
At high tide about 11am, the 90 or so volunteers also became stranded on the spit as they had to wait for the tide to recede so buses could arrive to take them back to base.
Nelson's Dean Caron volunteered yesterday and today. It was his first stranding as a Project Jonah volunteer.
"You could really contribute and help people out. It was such a rewarding experience."
Freelance photographer Katinka Visser from Nelson was taking photos of the stranding for Project Jonah, the second time she had done so.
"I love the noises they make," she said.
"You feel satisfied. I dug one whale out completely on my own which was really rewarding. It's heart wrenching but amazing to be so close to them."
Nils Alke of Germany was travelling in New Zealand and had come to the Spit to see some pictures and museum exhibits of past strandings. He found a real one instead.
"It was such a coincidence to see," he said.
"It would be even better to see them swimming in the sea."
Farewell Spit EcoTours manager Paddy Gillooly has attended about 10 strandings in the 25 years he has been a tour driver.
"From what I understand some of the ones that are left aren't that flash," he said yesterday.
"It depends on how high the tide comes tonight, which way the wind blows, because they are in a place where the tide will just float them. It depends on how strong they are when the tide comes in. You won't know anything until the sun comes up tomorrow morning."
This was the third stranding this summer.
The spot where the whales were stranded is close to where 25 were stranded early in January.
Seven of those whales died, while 65 whales died after becoming stranded in the same area in November.
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