Sources from the Ministry of Conservation said that it was estimated that a total of 416 whales were beached on Thursday night in a sandy area known as Farewell Spit, Efe news reported.
Dozens of lifeguards are working against the clock to keep the surviving whales alive until high tide comes while monitoring the situation of those that managed to refloat, the sources said.
This is the largest whales stranding incident in New Zealand.
In February 2015, an operation to save 200 pilot whales that were beached in the same area of Farewell Spit was carried out, but did not prevent the majority from dying.
The reasons why these whales have been stranded are still unknown, although the Golden Bay, which has shallow waters, is known for these kinds of incidents.
The pilot whale is characterized by its domed forehead and robust body that can grow to between six and seven metres long.