More than 50 whales dead after another mass stranding

Fifty pilot whales have been found dead after a mass stranding in the Chatham Islands.

Pilot whales are buried after stranding on the Chatham Islands. Source: Supplied

Initially, up to 80 whales were found beached at the southern end of Hanson Bay near Owenga township yesterday evening, but it was too late in the day to help the animals, the Department of Conservation said today.

When staff showed up at the beach this morning, they were relieved to find that about 30 or 40 of the whales had re-floated themselves without human intervention. However, another 51 whales remained - all of them dead except for one.

The remaining whale was euthanised by DOC staff.

"It was the most humane thing to do," said DOC Chatham Islands Operations Manager Dave Carlton. "This is always an awful decision to have to make."

The stranding comes only days after 145 pilot whales died on the shore of Stewart Island on Monday..

And eight pygmy whales beached themselves on Ninety Mile Beach in Northland last Sunday.