The wind was blowing, clouds blocked the sun and the sea was choppy and cold, but Hagai Mayer and his two friends didn't care. They wanted to see the sharks.

Every winter, as sea temperatures drop, sharks seeking warmer waters head to a northern Israeli shore, drawing enthusiasts who take the plunge in hopes of catching a glimpse of the enigmatic predators.

Dozens of sandbar and dusky sharks, which can reach up to three metres in length, converge by the bubbly stream of seawater used to cool the turbines of a power station near Hadera that is discharged back into the Mediterranean.

The site has become a magnet not only for sharks but also for researchers and people like Mayer, a resident of the nearby kibbutz Nahsholim, who on a cold February morning was preparing to go snorkeling.

"We're here to visit the sharks, we've been doing so for the past few years, whenever we have an opportunity," he said.

Seeing the large animals underwater in a natural habitat is "an adrenaline rush you can't even describe", he said.

"To me, encounters with wild animals in nature is the highest level of excitement, certainly with impressive animals like these," he added.

'No reason to fear'

Scientists are not entirely sure what draws the sharks to the small area below the four looming chimneys of the Hadera power plant, but it's clear to them that "it has something to do with the sea temperature", said Adi Barash.

The PhD student, researching sharks at Haifa University's Leon Recanati Institute for Maritime Studies, said the Hadera phenomenon, which exists to a lesser extent off smaller power plants in southern Israel, is not known to occur elsewhere in the world.

Sharks, according to Barash, have an unjustifiably bad reputation that is costing them their lives.

"The movie 'Jaws' created a very significant change in people's perception," promoting a "primordial fear that encourages mass killings of sharks, totally disproportionate to the danger they pose," she said.

"A shark is not dangerous, there's no reason to fear it," Barash went on, noting that more people die by slipping in the shower than from sharks.

"Of course you need to treat it with respect, it's a wild animal and a predator, but not dangerous to people."

There have not been any recorded incidents of sharks attacking people off Israel's Mediterranean coast for decades.

Getting up close

While sharks have been visiting Hadera for at least 20 years, their number has been on the rise due to the increase in the size of the power plant and enforcement of legislation protecting them.

Ran Golan, whose diving club "Out of the Blu" specialises in guiding people at the Hadera site, said that sunny winter weekends draw hundreds of people diving, swimming, snorkeling, boating or just observing the sharks from the nearby shore.

Barash, who heads the "Sharks in Israel" Facebook group, is also part of a coalition of experts and activists educating the Hadera site's visitors.

And while things can get hectic at times, Barash hopes "we will be able to make good use of the proximity between the public and the sharks, which is nearly impossible to create anywhere else".

'Like a horror film'

The stream from the Hadera plant creates turbulence that makes scuba diving in the relatively shallow waters challenging, and Golan briefs a pair of divers before leading them into the water that same chilly morning.

Exiting the water nearly an hour later, first-time shark diver Eyav Zuckerman was grinning broadly.

For most of the dive he didn't see much more than a tail, said Zuckerman, from Yokneam in northern Israel.

But as their time underwater was about to end, the group of four encountered two sharks, one of them crossing right in front of Zuckerman's face.

The limited visibility made the shark's unexpected appearance seem "like something out of a horror film", he said.

"But when you get that beautiful creature up near your face, the feeling is totally different," he said.

His experience seemed to have changed his perception of the marine predators.

"They must be more sensitive and shy than people say," Zuckerman said.