KEY POINTS:
Surf lifeguards are unsure whether to blow the whistle on a 2.5m mako shark which has been seen daily for the past week at Ocean Beach, 36km southeast of Whangarei.
The lifeguards don't know whether to get surfers and swimmers out of the water, or if the mako has taken up residency with a great white shark which has regularly appeared at the beach between October and mid-January but hadn't been spotted this summer.
Whangarei Heads Volunteer Surf Lifesaving Club patrol captain Rob Howes said yesterday the mako could be a new arrival or a small shark seen in the area over the past 10 years which had grown larger.
The mako had been seen off the beach last Friday, he said. It had "breached" (stuck its head out) in the surf on Saturday, was seen at Dead Horse Bay at the southern end of the beach on Sunday, swam underneath a surfer on Monday and was spotted again on Tuesday.
"We don't know whether it's a pregnant female which has come close inshore to breed or whether it has been hanging around for years," Mr Howes said.
"I was just about to jump in for some lifeguard training when it breached on Sunday and I changed my mind. If it breaches that close, it's becoming comfortable with people in the water."
There were about 100 swimmers and surfers in the sea when the mako breached but because the shark did not act aggressively, lifeguards decided not to blow the whistles they use to summon people from the water.
Mr Howes said lifeguards generally put their rescue boat in the water if sharks got close and used it to push them away.
He had emailed a shark expert for advice on whether Ocean Beach swimmers had to get used to the mako being around or if lifeguards should be pulling people out of the water when it was seen.
With Department of Conservation officials taking a summer break, shark experts were hard to locate this week but marine conservationist Wade Doak, of Ngunguru, had some soothing words of advice.
"The mako wouldn't put me off from going into the surf," he said. "A mako swam past when I was underwater at the Poor Knights years ago and there were always sharks around when we were diving to the Niagara [a ship carrying gold which was sunk by German mines off the Hen and Chicken Islands in 1940]."
Mr Doak said people just had to learn to live with sharks.
"There are always risks in life. I think you would be more likely to get hurt standing on a stingray than being bitten by a shark."
Mr Doak advised surfers to wear dark wetsuit boots when riding their boards so they were not dangling white legs in the water.
"Sharks have special vision which enables them to see low differences in contrast but not colours," he said.
"When a shark is looking up, it could spot a white foot on the surface but wouldn't easily see something dark."
Mr Doak said sharks did not specifically target people. "When a shark bites someone, it's usually a mistake."