Twenty beached whales returned to sea, one put down

Rescuers help save a whale that was stranded on Opoutere Beach. Picture / Fotopress

Rescuers today returned to the sea 20 of the 21 pilot whales found alive on a Coromandel beach yesterday, and put down the last, the Department of Conservation said.

Up to 70 DoC staff and locals kept the last of the live whales afloat until they were strong enough to swim away about midday today.

However, more than 50 of the pod of 73 whales, which lay undiscovered on isolated Opoutere beach until yesterday, had died.

There were no signs the refloated whales were returning to the beach, DoC's Hauraki area manager John Gaukrodger told NZPA.

"They all carried on well out to sea," he said.

"We've had both a helicopter over the top (of the pod) and a small boat operating out there as well. There's no sign of them."

But rescuers always had some concerns after refloating whales, which sometimes beached themselves again, he said.

"By the time they go it's a relief and to have them turn up back on your doorstep again can be quite demoralising."

The dead whales were buried in huge graves on the beach following karakia (blessings) from Hauraki kaumatua Wally Wells.

Although whales have beached in greater numbers over longer periods of time, Sunday's stranding was "quite a large number to have beached in one hit", Mr Gaukrodger said.

Many of those who turned up to help the whales belonged to whale rescue team Project Jonah, and were well trained for mass beachings.

"They become significant allies in these sorts of events," he said.

The whales were small -- 4m to 5m and 2 tonne to 3 tonne in weight -- and relatively easy to manoeuvre.

"They're also relatively placid. They can get agitated but if you've worked with them quietly, keeping them moist for 12 hours waiting until the next high tide, they get used to the people around them."

Getting stranded did not seem to have long-term effects on whales that were healthy before beaching, although they could get injured lying in one position too long.

"Once refloated, anything that keeps going, you presume that they have recovered quite quickly."

The stranding came as large numbers of whales and dolphins beached on Tasmania's King Island and Maria Island.

However, Project Jonah national stranding rescue co-ordinator Sheryl Gibney said the strandings were coincidental.

High offshore winds in the Coromandel area and plentiful mackerel near the coast may have been factors in that stranding.

Beachings could also be caused by one whale becoming injured or ill and the others responding to its distress signals, she said.

But Mr Gaukrodger said that despite vast amounts of research on the subject, beachings were still a mystery.

"I don't know of anybody who's hit the nail on the head yet," he said.

- AAP and NZPA