Volunteers helping stranded whales at Farewell Spit faced a near-hopeless task in what is now mainland New Zealand's biggest stranding since records began in the 1800s.
Farewell Spit is a 26km sandbar extending in an arc off the northwest tip of the South Island.
Its western flank is pummelled by the Tasman Sea. Inside its protective arm are the shallows of Golden Bay, and the tidal flats that have become a whale graveyard.
Since late Thursday, nearly 700 pilot whales stranded on, or near, the area.
Of those, more than 300 died, bringing the tally to almost 700 whales that have died in the area since records began.
DOC spokesperson Andrew Lamason said attention was now turning to how to dispose of several hundred carcasses.
Mr Lamason said officials wanted to keep the dead whales from washing into the bay on the high tides, so were considering building a fence around them until they decomposed.
Hundreds of people braved challenging conditions to help refloat the surviving animals. Daylight yesterday revealed a small miracle - all but about 17 of the extra 200 that beached overnight on Saturday had struggled free on the high tide.
By afternoon, they too had been saved. Volunteers were expecting to return at first light to see if any of those final 17 had restranded.
One of the volunteers said they had to cope with chilly conditions, the arrival of sharks attracted to the decomposing carcasses, and stingrays on the tidal flats.
Above the wind, and cries of desperate whales, Bridie Griffiths said the job of helping never gets easier. She grew up not far from the area and has attended several strandings, but this one was different.
"Oh, bigger than anything I've ever seen, for sure. I don't recall ever being at a stranding of this magnitude."
Mark Rigby of Project Jonah said nothing compared with it.
"It's one of the largest in recent years. We had over 200 on Valentine's Day two years ago. We're here for the welfare of the animals - to support DOC [the Department of Conservation] and to do anything we can to look after the welfare of these animals," he said.
"Whales are social creatures. Scientists believe that the reason we get mass strandings is because whales will respond to distress signals and group together, and strand together," he said.
Aucklander Deb Ward grew up in Golden Bay. She said strandings like this inspired an invention - a whale lifting machine. She and her husband Simon Ward created the machine that was trialled over the weekend.
"We saw a need for something to be done after being in whale strandings, when I was younger. We wanted something that would help get them back in the water quickly."
Serena Taylor, from Auckland's west coast, was visiting the region and joined the crowd of more than 500 on Friday who dug in to help.
Argentinian tourist Christian Bodesta cut short a visit to the nearby Abel Tasman National Park to help out.
Local tour operators shuttled helpers from the car park to the stranded whales about 2km along the beach.
Jess Worthington from Ruby Bay was at her first stranding. She said it was tough dealing with the sight of large numbers of dead calves - some still snuggled into their mother.
"They're just following their instincts and going where they think they're meant to be going. It's sad."
Paul Henare drove three hours from Nelson to help his partner, who is a volunteer with Project Jonah. She took leave from her job to attend.
Mr Henare was at his first stranding. He said it was a good feeling being able to help, but it was a shock seeing the number of lifeless whales.
DOC was criticised for not allowing the rescue to continue through the night, but Takaka-based ranger Mike Ogle said people had been injured in the past, working with black animals in the dark.
DCC said it would use scientific analysis to try to determine the cause of this latest mass stranding.