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Why you won't be attacked by a shark

ByAlison BruzekNOVA NextNOVA Next
white tip shark

These underwater predators aren't as dangerous to humans as we may think.

You know the scene: A woman’s legs kicking underwater. A black mass rising slowly from the depths. A triangular fin slicing through the water. For many, it’s that time of year when Jaws is on the mind.

But according to Oceana , of the nearly 500 species of sharks, only about a dozen are potentially dangerous to humans. Even for those species that are, humans aren’t preferred prey. Furthermore, they don’t attack people that often—certainly not enough to warrant their stereotype. In fact, sharks can be a greater danger to other sharks than to humans. Unborn sand tiger sharks, for example, have been known to devour their own siblings inside the womb. Not only are the sharks eating their fellow brothers’ and sisters’ bodies, but also the unfertilized eggs in a fit of “embryonic cannibalism.”

Juliet Eilperin, reporting for The Guardian , dove into the Florida Museum of Natural History’s International Shark Attack File and found that of the 80 unprovoked shark attacks on humans in 2012 worldwide, just seven resulted in death.

In other words, the odds are pretty slim. Eilperin elaborates:

More Americans were killed by collapsing sinkholes (16) than sharks (11) between 1990 and 2006, and more by tornadoes (125) than sharks (6) in Florida between 1985 and 2010.

You can minimize those chances even further by staying aware when in the water. Christopher Neff, a shark attack expert at the University of Sydney, explained to National Geographic that people should consider the following three questions:

First, I ask, “What’s the weather?” because swimming while it’s overcast or stormy isn’t a good idea. Incoming storms can cause the tide to stir up baitfish, and we want to avoid getting in the way of sharks and their prey. It’s recommended that bathers stay out of the water for 24 hours after a storm, not just [until] the next morning.

Second, “What’s the time of day and the environmental conditions?” We all know to avoid swimming at dawn and dusk and when the water is cloudy. But we also want to be conscious of other marine life and the seasons…

And third, “What am I doing?” Tips that can help reduce risk include not swimming alone or far away from shore. Simply put, swim in a group and stay close in.

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Should you spot a shark swimming menacingly toward you, there are a few things you shouldn’t do. David Shiffman, a Ph.D. student at the University of Miami’s Abess Center for Ecosystem Science, debunks a few shark fighting myths over at Smithsonian Magazine. For one, punching a shark in the nose is not necessarily the best option. Neither is playing dead, especially since some sharks like defenseless prey. Instead, you should go for the eyes—striking a shark’s eyelid-like protective barrier can surprise them.

Regardless, you can at least be sure you won’t be bitten by a Megalodon any time soon. (No matter how much respondents to a recent Discovery Channel poll want the ancient giant to be alive, the species is still very much extinct.)

For more shark facts, visit Ed Yong’s Not Exactly Rocket Science or follow marine conservation biologist David Shiffman on Twitter.

Photo by sharkbait/Flickr (CC-BY-NC-ND)

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