A pod of 90 pilot whales beached themselves at the top of New Zealand's South island Monday in the same area where seven whales died in a mass stranding earlier this month, officials said.

Regional conservation department manager John Mason said staff and volunteers would attempt to keep the whales cool until the late night high tide when it was hoped they would refloat themselves.

The whales came ashore at Golden Bay, near the tourist city of Nelson, where strandings on the tidal flats are common.

Earlier this month 25 whales were stranded on the same stretch of beach and only 18 were refloated, while 47 pilot whales died in the same area two months ago.

Pilot whales up to six metres (20 feet) long are the most common species of whale seen in New Zealand waters.