Photograph by Jim Abernethy, National Geographic
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A sand tiger shark in North Carolina.

Photograph by Jim Abernethy, National Geographic

Why Are So Many Shark Attacks Happening in North Carolina?

The state has had an unusual rash of incidents, though experts say the water is still safe.

Updated June 29, 9:30 a.m.

Two more swimmers have been bitten by sharks off the North Carolina coast. That makes six shark attacks in the state in the last three weeks.  

From 2005 to 2014, there were a total of 25 shark attacks in North Carolina. This year's incidents are part of a rising trend in the U.S. and much of the world over the past century (learn more about attacks). Overall, however, they remain relatively rare; an ocean swimmer has only a one in 11.5 million chance of being bitten by a shark, according to the International Shark Attack File at the Florida Museum of Natural History.

Why are so many recent attacks happening in North Carolina?

The Tarheel State typically gets one to two shark attacks a year but has had four this year, says Frank J. Schwartz, a shark biologist with the University of North Carolina, Chapel Hill. There were four bites there last year and 55 documented shark attacks in the state since 1905.

The incidents are heavily dependent on weather and currents and are much more likely when the water temperature reaches 80 degrees Fahrenheit (27 Celsius) and when strong currents flow north along the coast, bringing bait fish. This year, those conditions appeared in April, and sharks soon followed, coming from Florida and the Gulf of Mexico.

Why are shark attacks rising?

The most likely explanation is the “ever-increasing amount of time spent in the sea by humans, which increases the opportunities for interaction between the two affected parties,” according to the Florida museum. A steadily rising human population is also a big factor.

Is climate change to blame?

Schwartz says it’s unclear, since water temperatures and currents tend to show a high degree of flux from year to year. The numbers of attacks are also so low that statistical analysis is dicey.

Are children more at risk of shark attacks?

The child bit on Wednesday wasn’t necessarily at any more risk, says Schwartz. Although splashing can attract curious sharks, most bites are simply results of someone “being at the wrong place at the wrong time,” he says.

“Usually there is bait nearby and someone just gets in the way,” says Schwartz.

What kinds of sharks attack humans?

A number of sharks may be involved, including tiger, bull, great white, mako, nurse, black tip, white tip, lemon, and spinner sharks.

Why do sharks attack people?

The majority of incidents are “provoked” attacks, in which someone is bitten while spearfishing or while trying to catch a shark or release it from a line or net. Among unprovoked attacks, the fish are most often confusing people with their normal prey, often due to poor visibility. Surfers are most often attacked (as happened in Australia this week), most likely because they spend long periods of time in the water and often splash around like prey.

What should I do if a shark starts attacking me?

Hit it in the nose, which is often enough to end the attack, says the museum. Then head for shore.

If that doesn’t work, claw at its eyes and gill openings, two sensitive areas. “One should not act passively if under attack,” the museum says, because “sharks respect size and power.”

How do I reduce the odds of an attack?

Avoid swimming in known shark nursery areas, where bait is dropped, and swimming at night or during or after storms, which can make the water cloudy and churn up the bait fish that lead to shark feeding frenzies.

Avoid swimming with open wounds or shiny objects, and don’t go too far from shore or out alone.

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