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A woman was crushed and seriously injured yesterday by a dolphin in an accident described by a marine biologist as "three million to one".
Last night, she was in a serious condition in Auckland City Hospital after being flown there by helicopter.
Pauanui Coastguard jet rescue member Steve Taylor said the 27-year-old from Pukekohe was sitting on the bow of a 5.5m runabout "just cruising among some dolphins" at Slipper Island off the Coromandel when the accident happened about 2.30pm.
One of the bottlenose dolphins became "over-excited" and jumped on to the boat, Mr Taylor said.
The dolphin is believed to have landed on top of her, knocking her unconscious and inflicting serious head injuries.
It smashed a windscreen 3m up on the boat and plunged back into the sea apparently unhurt.
A second woman, also in her 20s and thought to be from South Auckland, was cut and bruised by flying pieces of the broken windscreen.
At least three people were thought to be on the boat.
The woman was unconscious when the Westpac rescue helicopter arrived at the island - about 8km off Tairua - about 3.50pm.
She had a cardiac arrest before being flown to hospital, and did not fully regain consciousness during the flight.
The helicopter landed in Auckland about 5pm.
Its advanced paramedic, Chris Deacon, said the crew had never been to such a job.
"That would have to pretty well be the first time a dolphin's hit a human. I've never heard of it before."
The woman's boyfriend, who was not injured but was distressed, accompanied her on the flight.
The incident has mystified Otago University marine mammal biologist Liz Slooten, who said it was extremely unusual.
"The number of dolphins that injure, let alone kill, a human would be one in 100 years."
Dr Slooten, who has studied dolphins for more than 20 years, put the odds of such an accident at "three million to one" and "way more rare than being struck by lightning".
Dolphins seldom became aggressive in the company of humans, but could get agitated or confused when a large number of boats were around.
Tairua Dive and Fishinn manager Dave Early was returning from a boat trip when he answered a distress call from a boat in South Bay.
He was told that a dolphin "just came out of the water and landed on their boat".
Barbara Needham, whose family has owned Slipper Island since 1971 and operates a resort there, said dolphins visited the area all year round.
The pod involved in the incident had been there a week and people had been swimming and boating out to see them.
"They've just been fantastic, doing aerial displays and everything," Ms Needham said.
Many boaties from Tairua and Pauanui visited South Bay on the island for picnics.
"The dolphins seem to be attracted by boats, so whether there were too many boats and not enough room for everybody, I don't know."
About six campers at the bay heard the crash when the dolphin leaped on to the boat.
"We were looking at the pod of dolphins come past when we heard an almighty whack," said Darren McGlone, 40, of Tairua.
Another man, who did not want to be named, said about 50 dolphins were in the pod.
"One jumped out and landed on top of the boat and smashed the windscreen and bow rails, thrashed around and leaped out again, leaped off the front of it."
He said nearby boats rushed to the damaged boat's aid and it was driven to shore.
The dolphins in the pod were about 3m long.
Mr McGlone said the damage to the boat, which had a half-cabin and which he described as a Signature model, was bad.
"It looked like an 80kg dolphin going through the windscreen of your car."
