(AP) -- Rescuers who battled exhaustion and darkness succeeded in saving 14 pilot whales from a pod of 74 that stranded on a remote New Zealand beach.
Late Friday, a total of 24 whales were trucked 30 miles (50 kilometers) from Spirits Bay, where they beached on Wednesday, to be refloated in more sheltered waters of Rarawa Beach, an hour's drive south.
Two died en route, another on the beach and seven had to be euthanized after re-stranding.
Rescuers in boats and on shore worked strenuously to prevent those seven whales from beaching themselves again but were unsuccessful, Department of Conservation incident controller Jonathan Maxwell said.
"By that stage it was dark, and all of us were pretty exhausted. We all agreed we had done everything we could for these animals. The most humane course of action was to end their suffering," Maxwell told the New Zealand Herald.
The whales were transported between beaches in six trucks packed with straw and sand, in the largest operation of its kind in New Zealand.
Department of Conservation staff and volunteers used three boats and two jet skis to herd the whales out to sea, Doc community relations manager Carolyn Smith said. Twenty-one were eventually guided into the open sea but seven turned back to land.
"As far as I'm aware, this has not been tried before to this scale (in New Zealand)," Anton van Helen, a whale expert at New Zealand's national museum, told the Herald. "Its a huge undertaking and definitely contains risks for the whales, but is basically their only chance."
New Zealand has one of the world's highest rates of whale strandings, mainly during their migrations to and from Antarctic waters, one of which begins in September.
Since 1840, the Department of Conservation has recorded more than 5,000 strandings of whales and dolphins around the New Zealand coast. Scientists have not been able to determine why whales become stranded.
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