This Summer, Shark Deterrence Is Going High Tech
Following failed attempts to reduce shark attacks through culling, Western Australian scientists are developing futuristic methods to keep swimmers safe.
This post originally appeared on VICE Australia.
Between 2000 and 2014 there were 14 shark fatalities off the coast of Western Australia. And while that's not a super large number (64 people died from road accidents in the state in 2014 alone), death by shark looms large in Australia's national psyche.
Most of those WA deaths are believed to be caused by Great Whites, and as a result the State Government adopted a controversial policy to catch-and-kill sharks off Perth and the southwest beaches. Throughout the first four months of 2014, 172 sharks were caught and 68 shot; yet none were found to be man-eating Great Whites. The policy was quickly abolished following fierce opposition from the public and the world's top marine scientists arguing it didn't make beaches safer.
Around Australia, the most popular methods of dealing with sharks are still a combination of nets and drumlines. Queensland employs both, and as a result between August 2013 and August 2014 667 sharks were killed off the coast along with about 100 dolphins, turtles, and dugongs.
So although we're in the middle of winter, it's not surprising that discussion has begun over how to make beaches safer this summer. Following last year's public backlash over culls, scientists around the state are researching and developing new methods to deter sharks without spilling blood.
At the University of Western Australia this discussion is being led by The Ocean's Institute's Professor Shaun Collin. Shaun's group has been exploring avenues of frightening, but not harming, sharks. "We are using our basic knowledge of the sensory abilities of sharks and their relatives to develop novel deterrence," he explains. They've experimented with strobe lights, sounds, and bubbles to deter attacks—but have received varying degrees of success.
Bright flashing lights were found to be effective as shark deterrents and did discourage sharks from biting. However they appeared to be only effective with nocturnal and bottom-dwelling shark species, not the more dangerous Great Whites.
Loud underwater sounds, including artificial and natural orca calls, were not effective at deterring small sharks in the laboratory and had only a slight preventive effect in the wild.
Short bubble bursts did deter sharks, especially Great White sharks, but again only for a short time. After which sharks became used to the bubbles and did not hesitate to cross the bubble barrier.
Something they've had more luck with is the Shark Shield. This is an electrical device that can be attached to an ankle, surfboard, or kayak, and has been found to have a substantial effect in deterring a range of shark species—including Tiger sharks and White sharks. According to Professor Collin, "It emits a strong electric field which interferes with their electroreceptive system and was shown to be successful in nine-out-of-ten cases, without harming the sharks."
Another ambitious project has been the Shark Attack Mitigation Systems (SAMS). Working with the UWA's Ocean Institute, Optus, and Google, they have been developing a Clever Buoy that uses sonar technology to detect shark-sized objects in coastal areas. Once detected, a signal is transmitted to warn lifeguards on the beach.
Despite setbacks, the group's work has caught the attention of the State Government which has provided $646,000 AU [$480,000 US] over a two-year period, for research and development.
As Professor Collin re-iterated, "Once the results are published, the investigations will provide valuable insights into the effectiveness of existing shark deterrents and reveal a range of interesting findings about the sensory world of sharks."
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