Image via Flickr Creative Commons
In 2002, scallop diver Paul Buckland was making a typical dive off South Australia's west coast when something went wrong. He was wearing his SharkPod, a device that emits an electromagnetic field to protect divers from the ocean's top predator, but it didn't function properly and he was pulled back into his boat missing one leg and half his torso after a six-meter white pointer shark used his flesh as a mid-day snack.
Anti-shark technology companies such as SharkShield, the makers of the SharkPod, have promised divers, surfers, and snorkerlers for years that they could float through blue waters without fear. SharkShield's website even claims to sell "the world's only proven, tested shark deterrent technology," yet additional research and a flawed track record suggest that the machinery available on the market is inconsistent and unreliable when it comes to safe dives in dangerous waters. Yesterday, however, a company called Shark Attack Mitigation Systems unveiled two new wet suits that are changing the scientific approach to reduce shark attacks.
Since the early-'90s, scientists and marine biologists have focused on deterring sharks by irrating the creatures' ampullae of Lorenzini, the jelly-filled sensors that certain fish use to scan electric fields under water. The POD (protection oceanic device) was the first electronic machine deigned succesful after South African company Natal Sharks Board marketed the product and had shark experts and Jaws-consultants, Ron and Valerie Taylor, test the innovation in 1992. The duo made a documentary on the technology in 1996 called Shark POD, but there have since been debates and research that contradict the effectiveness of such anti-attack measures.
Above is a SharkPod being tested in Australia via SharkShield
Last year, ABC Australia published an article saying that recent POD tests yielded ineffective results. Researcher Charlie Huveneers used seal decoys in South Africa and static tuna bait in South Australia to test if the electromagnetic pulses would repel Great Whites. He claimed that they found no differences in the proportion of static bait being eaten by sharks regardless of the shield. Meanwhile, in South Africa, the PODs were more effective in deterring an attack compared to dives without the device, but they still failed to repel Great Whites again and again.
Also worth noting is that the bulky SharkShield POD products can cause muscle spasm in humans (see the website's FAQ section "Will I get an electric shock?"), suggesting this isn't the most fool-proof tech. It is unsure if the sharks have learned to ignore the PODs, but the machines are definitely not a guarantee that you can go swimming with a Tiger and make it back to shore unscathed.
Enter: Shark Attack Mitigation Systems (SAMS), the "world-first 'invisibility cloak'" that was developed by scientists at the Unversity of Western Australia (UWA). It's known that sharks are color-blind, yet have extremely advanced eyesight with regards to perceiving shading. They see shapes and colors differently than humans, as their vision is based on the "reflective spectrum" in the water. SAMS has capitalized on this aspect of shark biology to flip the model of how to approach shark shields.
The SAMS website's testing and science category notes that by using "specialized molecular biology techniques" the company was able to analyze genes that form the retinal visual pigments of large sharks such as Great Whites. This allowed the scientists to develop wetsuits that are essentially shark camo; patterns and coloring that is either unrecognizable or visually threatening to the finned behemoths.
The blue and white "Elude" suit makes it hard for sharks to see the user as they blend into the background water colors and is designed with divers in mind. The other suit, called the "Diverter" is black and white in a striped pattern to mimic the coloration of poisonous of fish such as the pilotfish, which often shadows sharks in hopes of eating ectoparasites around the host species. Sharks know that these fish are life-threatening and thus avoid them. The "Diverter" is meant for surfers who will be close to the water's surface and don't want to pull a Fonzy.
The "Elude" suit for divers from the SAMS site
The company is expected to start more testing once it becomes summer in South Africa, but this may be the breakthrough needed in shark evasive technology. Scientists could feasibly wear the SAMS designs and also use a SharkPOD for more security, but the casual snorkerler or surf enthusiast will most likely not want to carry a bulky POD while hanging 10. Thus, these new wetsuits might be the best saftey precaution that a ocean lover in the southern hemisphere could take.
Maybe tricking the sharks will work better than trying to repel them. It will take more testing before these suits can be a confirmed success, but they're provoking us to get back in the water and live every week like it's Shark Week.
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