Chris Hemsworth gets has an unusual close encounter with a great white in new shark doco

Chris Hemsworth tries to answer the age-old question of whether humans and sharks can coexist in the oceans in a new documentary.

Action man Chris Hemsworth probably wasn’t counting on a close encounter with a shark’s butt when he set out to film a conservation documentary for National Geographic for its annual SharkFest.

The Thor star and mad keen surfer set out to spotlight the technology being trialled to reduce attacks without harming sharks after last year’s tragic eight deaths in Australian waters.

Chris Hemsworth with a grey nurse off Fish Rock on the NSW mid-north coast. Picture: National Geographic

Shark Beach with Chris Hemsworth features his surfing champ mate Mick Fanning and revered ocean activist Valerie Taylor alongside leading scientists including Dr Paul Butcher.

The actor joined Dr Butcher to inspect his Smart Drum Lines off the NSW mid-north coast which catch great whites, send an alert to the team who head out to the buoy, tag the shark and release it.

The tag not only gives scientists invaluable data about the movement and behaviour of more than 400 sharks tagged in the program, but sends a ping to an app to warn beachgoers if the animals return to within 500m of the shore.

And after they stabilised the shark, Hemsworth was tasked with taking a DNA swab of its butt. Picture: Hemsworth, Dr Butcher and his team pulling in a shark to the boat. Picture: National Geographic

During one catch of a 2.8 metre male great white, Hemsworth is tasked with taking a DNA sample from the shark to study its diet.

“Here we are about to take an anal swab from a shark; it’s all for science … where is its butt?” Hemsworth said.

The novice diver also heads underwater with Taylor to observe the protected grey nurse colony of Fish Rock, off the mid-north coast of NSW.

Without a hammer, or anything else to protect him, the actor was a little unnerved about his first close encounter with a shark in the wild, holding onto Taylor’s hand as they descended through the murky water around the rock.

Poor Thor got a wee bit seasick waiting for sharks. Picture: National Geographic/Craig Parry

She asks if he’s OK and Hemsworth gives a hesitant yes before revealing “although 40 feet underwater looking for giant sharks, I do wish I could see a bit further.”

He is spellbound as up to five of the huge beats swim above him.

“Coming face-to-face with them, it’s hard to put into words the serene beauty of these magnificent creatures. Up close you see the grey nurse’s jaws are filled with over 100 needled-sharp teeth,” he said.

Another scientific marvel in development by a Flinders University team including marine ecologist Charlie Huveneers is a personal electronic deterrent which could be fitted onto surfboards.

Their tests off the Neptune Islands of South Australia found the electric field generated by the device could reduce shark bites by 60 per cent. The field repels the shark from the “bait” because the predators have an unusual sensory organ which uses electro perception when going in to bite prey.

The documentary only partially seeks to understand why there has been such a dramatic increase in human and shark encounters, limiting the conclusions to the greater numbers of people swimming and surfing and global warming of the oceans pushing more marine animal life closer to shorelines.

Sharks ain’t gonna stop Hemsworth or Mick Fanning from surfing. Picture: National Geographic/Craig Parry

“There’s definitely been an increase in activity between people and the ocean and sharks, in particular,” Arakwal traditional owner and artist Nickolla Clark tells Hemsworth.

“And a lot of the places people go here on country … is these beautiful beaches right next to rocky outcrops where sharks nest. It’s their domain, it’s their home, they’ve always been there.”

About that day in South Africa … Fanning shares the impact of his famous shark encounter in South Africa. Picture: National Geographic/Craig Parry

After a surf together, Hemsworth asks Fanning to retell his infamous experience with a great white during a contest in South Africa six years ago.

“Things have changed now. I see everything on the water now. And I’m still scared of hearing splashes behind me … I jump,” Fanning said in the doco.

“If I don’t feel right, I just go in these days. It’s just … not worth the risk.”

Shark Beach with Chris Hemsworth screens on the NatGeo channel on Foxtel at 7.30pm on July 5.

Originally published as Chris Hemsworth gets has an unusual close encounter with a great white in new shark doco