Do you have pictures of the stranding to share?
Twenty-two pilot whales have died after a pod of 99 stranded at Golden Bay at the top of the South Island today.
Department of Conservation (DOC) area manager John Mason said an aircraft pilot spotted the pod "milling around" in the area.
"They were discovered about 10am this morning by a local pilot who was doing a flight over the base of Farewell Spit, and he saw the whales, looked at them and decided they were probably going to strand, and gave us a ring."
DOC workers tried to coax the "confused" whales out towards deeper water but the whales were unresponsive and were left stranded as the tide receded, he said.
This evening 70 DOC staff, helpers and Project Jonah volunteers were trying to keep the whales comfortable, covering them with wet sheets and pouring water on them, he said.
High tide - the prime time for refloating the whales - was not until 10.45pm and because of safety issues the volunteers and staff would leave the beach at about 9pm.
"It's too dangerous, we're dealing with whales that are three, four, sometimes 500 metres offshore, they're big animals, we're standing in chest deep water ourselves, it's just not a situation you want to be in."
While they were hoping the whales would refloat themselves at high tide tonight they were not optimistic it would happen, he said.
"They're quite a long way up the beach and they're in quite a difficult location to refloat themselves, so while we're hoping they manage to get themselves off we won't be surprised if we see them in the morning."
Volunteers and staff would be back at the beach at first light tomorrow morning.
The next best time to refloat the whales was at high tide at 11am tomorrow morning, he said.
"They're going to be in poor physical condition and ... the longer they spend on the beach and the more tide cycles they go through the less chance of a successful refloat. Having said that we have refloated whales that have been through three tide cycles so you can certainly do it."
It was the third whale stranding in the area this summer, which was unusual, he said.
"We generally get one stranding a summer and we occasionally get two, but since I've been here in the past 10 years we've never had three."
Earlier this month, 18 of 25 whales were refloated when they stranded in Farewell Spit. A pod of 65 whales were lost when they were stuck on a remote section of Golden Bay in November last year.
He said the largest stranding in his time had been 117 whales, so the number this time was not out of the ordinary.
It was not known why whales stranded in different parts of the country, he said.
"A lot of speculation has gone into the question of why whales strand in particular places, and the most prevailing theory is that it's because of the geography of the area.
"You've got these very flat areas of seabed, and because whales work on a sonar system, the theory is that they get disoriented and they can't work out where the deeper water is, so they just mill around and eventually strand."
A spokeswoman from Project Jonah said they were "hopeful" most of the whales would survive.
"Luckily whales that strand are usually healthy and well, which gives them a good chance of survival. Unfortunately it's usually very difficult to save them all."
Golden Bay was a notorious hot-spot for strandings, she said.
"The spit extends right into their migration path so if they catch the tide at the wrong time it can be really treacherous."