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Inside the Rage Cage: the Stubborn Evolution of Shark Defense Tech

It takes a special sort of person to plunge into baited waters and stare down 2 tons of brute, cartilaginous fury barreling out of the gloom at ramming speed. That’s probably why getting up close with predatory sharks is still a relatively nascent...

It takes a special sort of person to plunge into baited waters and stare down two tons of brute, cartilaginous fury barreling out of the gloom at ramming speed. That's probably why getting up close with predatory sharks is still a relatively nascent endeavor, as with the industry and technologies that have cropped up around shark diving.

We're all familiar with the observation cages of so many television nature programs. Fastened to the sides of research vessels, or lowered by weights or wires to the seafloor, these contraptions are charmingly steam-punkian, bobbing slightly as Captain Nemo safely confronts creatures of the deep. Accidents involving cages are rare, despite media frenzies. But, however effective, cages just seem like accidents waiting to happen. Right? They seem archaic, frail enough to rattle apart from one perfectly placed tail thrash.

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Is this really the best we can do? There has to be a better way. Spheres of reinforced glass, possibly? Force fields?

Not really. Shark cage tech is decidedly stubborn. "The original genesis of the cage came from such a perfect place," says Pat Douglas, CEO of Shark Diver, a worldwide commercial shark diving company, that there's really no need to fix what isn't necessarily broken. But there have been some interesting innovations along the way. These date back to December of 1963, when Rodney Fox was nearly gnawed in half by a great white shark.

Fox, then 23, was attacked while spear fishing off south Adelaide, Australia. The beast struck Fox's midsection, shredding open his abdomen, snapping all ribs along his left side, puncturing his diaphragm, tearing open a lung, piercing a scapula, uncovering his spleen, exposing his heart's main artery, and crushing his right hand. His wet suit literally held him together, though he teetered on the edge of vein collapse from excessive blood loss. It took 462 stitches to sew him back up. To this day a shard of tooth remains lodged in his right wrist. Gnarly.

He'd go on to pioneer underwater observing. Fox was the first to use one-inch square tubing of hollow aluminum to construct now classic breadbox-style shark cages, like those he built for Jaws.

From here Fox tweaked his design to allow a cage to be dropped some 40 feet to the seabed. (This was a boon to oceanic research, offering unprecedented views into the behaviors of food-chain keystones, undisturbed and in their element.) Interior flotation pods could pump the cage back to the surface. The drop-down cage, as it's now known, "was a very rudimentary submarine," according to Douglas.

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Meanwhile, South African divers decided they wanted a piece of the action. They started building cages, but using only reinforced steel bars and chicken wire. Dangerously cheap, yes, but ballsy. (They still prefer this model.)

Australian paua divers harvesting abalone were looking for ways to reduce chances of great white attacks around this time, as well. They devised a tubular, thruster-powered contraption that could putter around the seabed. The design held patent from the late-’70s through 1996. It was an experiment, if anything. Was it innovative? "I don't know," Douglas admits. "I don't even think you could call it a cage, because it's ambulatory at that point."

This was the state of shark diving tech when Shark Diver came onto the scene a decade ago. How could they make a better breadbox?

Flotation was key. Around this time many dive teams, aside from Fox and his son, Andrew, and the chicken-wire South Africans, were using foam-filled PVC piping on their cages. But PVC is photosensitive. Take a hammer to, say, two-inch thick, tubular PVC left out in the sun all summer and it'll shatter like glass. So Douglas and his crew fashioned their flotation pods using vinyl-jacketed foam cores. Douglas claims they can withstand 12-gauge shotgun blasts: "And being vinyl, they last."

They're getting attention, too. In addition to scouting new dive spots around the world, and even setting up shark-diving protocols for antonymous vehicles off the Hawaiian coast, Shark Diver is providing expertise on boatloads of film and television projects, most recently this commercial for some razor company:

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Fox's breadbox is still industry standard, by and large, give or take these occasional and slight modifications.

Efforts to best the tried and true have been spotty. Spheres or boxes made from bulletproof glass, or any other sturdy and transparent material, can knick and scratch easily, which makes observation diving pointless. A more promising shark deterrent could be PODs, or protective oceanic devices. PODs beam out electromagnetic pulses designed to disturb ampullae of Lorenzini – the jelly-filled patch of ultra-sensitive electroreceptor pores on the underside of a shark's snout – and are small enough to be secured to dive tanks or belts.

It should be mentioned, though, that Peter Clarkson, a known abalone expert, was mauled by a pair of white sharks last February. Clarkson is said to have once praised Shark Shield, a POD maker, in a written testimonial. It's unclear whether he wore a POD at the time.

(credit: dailytelegraph.com.au)

The misconception is that shark cages protect humans from sharks. They do, to an extent. But cages are really there to protect mega-fauna that are typically uninterested in humans from bumbling, idiot humans, whose limb thrashing and operator errors confuse sharks, sometimes enough to trigger primal instincts. In fact, cages "really aren't designed" to withstand the thrust and torque of 15 – 16 foot, 2,000-pound animals, Douglas admits. So in a way the strength of cage tech's commendable unchangingness is essentially built on a whole lot of luck, plus a lot of common sense out of divers and operators.

It's like shooting a gas tank. You can bait a big white shark into a cage 300 – 400 times and the brute will just bounce off. You can fire 500 bullets and. . .nothing. But then, on shot number 501, the tank explodes.