More than 400 pilot whales have stranded at Farewell Spit in Golden Bay.
DOC Golden Bay operations manager Andrew Lamason said latest reports were that an estimated 70 per cent of the 416 whales had died overnight.
The focus was now on keeping the remaining whales alive until high tide at 10.30am.
It is the third-largest stranding on record. A thousand whales stranded on the Chathams in 1918.
Lamason is urgently calling for volunteers this morning to help rescue the whales stranded about four kilometres from the base, on the inside of Farewell Spit.
He said it was essential that rescuers had a wet suit and could look after themselves for the day with food and water. High tide was at 10.30am so the next few hours were critical.
Lamason said the whales were first spotted swimming close to shore by a DOC ranger in the area late last night. At first light this morning the stranding was confirmed.
“It’s a big one,” Lamason said.
He asked rubber neckers to stay away from the site.
“We want to be in the business of saving whales, not people,” Lamason said.
If rescuers could car pool that would also help because of the narrow access road to the Triangle Flat car park at the base of the spit.
Project Jonah is sending its medics and other volunteers to the site.
The long, curving spit is a prime site for whale strandings.
A reporter at the scene Nina Hindmarsh said it was a really emotional atmosphere.
The whales were “thrashing around” and volunteers had to be really careful of the animals.
About 90 more volunteers had arrived at the scene at about 9am.
The whales were spread out over a huge distance about 500 metres out to sea.
Farewell Spit Eco Tours manager Paddy Gillooly, who was helping with the rescue, said conditions were working in their favour.
“Now that the tide has come around, the live ones are starting to move,” Gillooly said.
“Everyone is working hard to refloat the whales.”