Cape scientists’ eco-friendly shark-repellant technology to be adopted worldwide

Cape marine biologist Sara Andreotti and her team, who have helped pioneer eco-friendly shark barrier technology on our south coast, are now introducing the technology to the Bahamas, marking a significant milestone in marine conservation. The innovative system, known as the SharkSafe Barrier, exploits sharks’ natural magnetic senses, used to detect other fish, by deploying magnetic fields to create a non-lethal separation between humans and sharks.

During a recent construction project in the Bahamas, the team received an unexpected visitor in the form of a manatee. According to Andreotti, this encounter offered compelling evidence of the barrier’s effectiveness, as the technology is designed to specifically deter sharks while allowing other marine creatures, such as manatees, to swim freely.

The SharkSafe Barrier, developed by marine biologists at Stellenbosch University and manufactured in South Africa’s Western Cape, has the potential to replace traditional shark nets, which inadvertently harm thousands of sharks and other marine species each year.

The technology replicates the visual effects of a kelp forest and combines it with a series of permanent magnetic stimuli to form a deterrent for sharks. As the installation at the Berry Islands in the Bahamas demonstrates, it strengthens marine conservation efforts in the region. The Bahamas declared the first shark sanctuary in the Atlantic Ocean in 2011, contributing significantly to the local economy through shark tourism.

The success of the system in the Bahamas led the team to contacts many other countries worldwide, including New Caledonia, Réunion, Australia, Mexico, Brazil, Egypt, and Dubai, to explore further installations. In South Africa, they are exploring the possibility of trialing the technology in Plettenberg Bay, but local funding is a challenge compared to wealthier overseas clients.

The SharkSafe Barrier is the culmination of 15 years of research and development. The design drew inspiration from the behavior of marine animals that seek refuge in kelp forests to avoid predatory sharks. By replicating the electromagnetic image of the kelp forest environment, the barrier acts as an effective deterrent. The barrier incorporates strong magnets, which, rather than attracting sharks, overstimulate their natural receptors on their lateral line organs, further repelling them.

Manufactured locally in Cape Town, the SharkSafe Barrier consists of high-density polyethylene pipes that are anchored on the seabed in a grid-like structure. The grid is weighted down by cement blocks, creating an artificial reef that encourages marine life to settle.

By deploying the SharkSafe Barrier, the team aspires to support marine life and allow humans to enjoy the oceans safely, marking a “win-win situation” for communities reliant on ocean-based activities for their livelihoods. The technology also aims to replace the use of shark nets in South Africa, a practice responsible for unnecessary marine life casualties.

In a world where alternatives are needed to protect both humans and marine life, the SharkSafe Barrier presents a promising solution that maintains the delicate balance of our oceans, and a proud achievement by our local scientists.

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