Can Swimmers and Sharks Coexist? Smarter Maps Might Help


Medici’s demise was the primary shark fatality in Massachusetts since 1936. “We’re on a trajectory, proper?” says Doyle. “It was three bites in 14 months.” After her pal’s paddleboard scare, Doyle cofounded Cape Cod Ocean Neighborhood, a bunch that finally turned a nonprofit devoted to growing public security. The group has helped join pilots with lifeguards to alert them to doable sharks. It has raised funds for drones and big car-sized balloons with high-definition cameras that would spot sharks, and it has advocated for units such because the Intelligent Buoy, a marine monitoring and alert system that detects giant marine life within the water.

However a six-month research commissioned by the Outer Cape cities and launched in October 2019 seemed on the efficacy of greater than two dozen shark mitigation methods, together with the Intelligent Buoy, in addition to nets, digital limitations, electromagnet units to discourage sharks, and drones, amongst others. The report finally concluded that almost all both didn’t have sufficient proof they really labored, had restricted efficacy, or wouldn’t work on Cape Cod’s shoreline—besides one: modifying human habits.

This has been the first method that public security officers have mitigated shark danger over the previous eight to 9 years, mentioned Suzanne Grout Thomas, director of neighborhood companies for Wellfleet, a fishing city about 15 miles from the tip of Cape Cod. Since Medici’s demise, cities have stepped up their protocols, limiting how far out folks can swim and shutting seashores to swimming generally a number of occasions a day. Lifeguards and even some members of the general public are educated in “cease the bleed” practices for bites, whereas indicators warn in regards to the presence of sharks. “Our greatest contribution to that is educating most people as to how sharks could be anticipated to behave,” says Thomas. And he or she already sees indicators it’s working. Folks swim nearer to shore, or don’t swim in any respect, they usually react sooner when the lifeguards blow their whistles to clear the water.

Final summer season, Wellfleet had two buoys that despatched a sign to lifeguards. If a tagged shark got here inside 200 yards, they might name swimmers out of the water. “There have been a whole lot and a whole lot of sharks that pinged these buoys final summer season,” says Thomas. Her aim is to have one at each seashore.

However this strategy, she acknowledges, has its limitations. Not each nice white shark is tagged, and cellphone community service on the Outer Cape seashores continues to be spotty at greatest, that means any dwell notification programs are troublesome to share broadly.

As researchers and residents think about the perfect mitigation methods, one technique—culling—has stayed off the desk. That’s an strategy some nations have tried. Western Australia, for one, carried out a regional coverage in 2012 to trace, catch, and destroy sharks that posed an “imminent risk” to beachgoers. In response to the Worldwide Shark Assault File, a worldwide database, shark assaults in Western Australia have been on a downward pattern, however prior to now couple of years they’ve spiked once more. Whereas estimating the results is troublesome, many specialists say culling tasks don’t work.

Now, technological advances and a rising understanding of animal intelligence are giving researchers hope that one other administration choice could also be on the desk, one which seeks to grasp, somewhat than modify, shark habits.

The ocean ground of the Cape is an immense patchwork of sandbars, shoals, and deep trenches. Sharks have discovered easy methods to navigate this underwater labyrinth. They now hunt in what some name “the trough,” a deep space of water that types just like the letter C between the outer sandbar and the seashore. As a result of seals are sometimes present in these shallow waters near shore, the sharks have discovered easy methods to assault laterally, somewhat than ambush from beneath. In reality, not like in different areas of the world, sharks on Cape Cod spend round half their time in water shallower than 15 toes, in keeping with a latest research that analyzed knowledge collected on eight nice whites.


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