Traditional shark nets are known as 'walls of death.' A new eco-friendly barrier uses magnetic fields to deter sharks instead of trap them.

• Shark bites are very rare, but they can be fatal.
• The SharkSafe Barrier uses magnets to deter sharks from areas with swimmers.

Earlier this month, a woman paddleboarding in the Bahamas was killed by a shark, CNN reported.

Fatal shark attacks are incredibly rare but still a real concern for swimmers, surfers, and other ocean users. That said, nets used to deter sharks are a major concern for the animals.

An average of 10 people die from shark attacks each year whereas tens of thousands of sharks have died over the decades from barrier nets designed to keep them out of popular coastal waters.

That's where the SharkSafe Barrier comes in, which uses a completely different approach to deter sharks with magnetic fields that could save both shark and human lives.

A barrier that can protect both humans and sharks

The Bahamas designated its waters as a shark sanctuary in 2011, which has helped make it the shark diving capital of the world, Steven Kessel, director of marine research at the Shedd Aquarium, told Business Insider.

"Tiger sharks, bull sharks, and hammerheads are very prevalent there, and people really travel from all over the world to reliably dive with those species," he said.

The designation also means that any mechanism for deterring sharks in Bahama's waters must be safe for the animals, too, making it a prime spot to test out SharkSafe Barrier.

Over the summer, divers installed 98 feet of polyethylene pipes, cement blocks, and magnets around a private island's beach enclosure in the Bahamas' Berry Islands.

"Sharks are sensitive to magnetic fields because they have a special organ called ampullae of Lorenzini distributed around their eyes and nose," Sara Andreotti, the COO of SharkSafe Barrier told Business Insider via email.

Therefore, the presence of a strong magnet could potentially overwhelm that system, Kessel said. He compared it to a person getting a whiff of smelling salts, "a real shock to the system," he said.

The magnets probably wouldn't affect most other marine animals, though they might be put off by the physical barrier itself, Kessel said.

Another major benefit of the barrier is the way it looks.

"It looks like a thick forest of kelp," which sharks don't usually like to enter, Andreotti said.

Why are shark nets deadly?

Traditional shark nets have been used in waters off of parts of Australia and South Africa for decades. Critics call them "walls of death."

"They have large mesh designed to trap and suffocate marine animals" when their gills become caught, Andreotti said.

"Many species of sharks need to swim to breathe, to respirate," Kessel said. "So when you restrict their movement, they essentially suffocate."

The stress of getting caught can also be fatal, he said. Predators get easy access to entangled prey, too.

And sharks aren't the only victims. The nets also capture rays, marine mammals, and large fish, Kessel said.

Instead of trapping sharks, SharkSafe's magnetic barrier is supposed to repel them.

A barrier that offers peace of mind

Andreotti helped develop the SharkSafe technology, combining two ideas from Michael Rutzen, a South African cage diver, and marine biologist Craig Patrick O'Connell.

Rutzen envisioned an artificial kelp barrier to keep sharks away from humans, and O'Connell wanted to use magnets for the same purpose.

O'Connell has since left the SharkSafe Barrier company and told Forbes last year that he doesn't think magnetic deterrents are an effective solution for sharks. The company told Forbes it disagrees with his assessments.

Andreotti said the company ultimately hopes to replace shark nets in South Africa and Australia and culling programs that kill sharks in other parts of the world.

Kessel said he thinks a truly motivated shark might be able to get through such a barrier, but he would love to see a safe shark-net alternative.

"The chances of getting bitten randomly by a shark in the wild are so, so small that I think you can provide peace of mind with something like this," he said.