Shark Week: Why all the attacks?

Shark Week is coming to an end and I’m sure most of you have heard about the following shark events in the news: North Carolina has had a record-breaking number of shark attacks this summer, 8 attacks as of July 6th and the highest since the 80’s. The severity of injuries ranges from a slash on a boy’s heel to two teens losing limbs (read more about it here). Most attacks occurred along the Outer Banks – Ocracoke Island, Cape Hatteras, Surf City, Ocean Isle, and Oak Island – and in shallow water. Scientists suspect that several species of sharks have been involved, including a bull shark or tiger shark.

bullshark

Additionally,  two great whites (Katharine and Genie, tagged and tracked by scientists from Massachusetts Division of Marine Fisheries) have made visits to Pamlico Sound earlier in the year. Katharine stopped by in January and makes a trip along the Outer Banks each year; Genie was spotted in Pamlico Sound in mid-April. With all of the attacks and shark sightings people are asking why?

Some claim that the number of sharks in the ocean has increased, but shark populations have been declining due to overfishing for their fins (NOAA says a little more about conservation efforts). So why have there been more attacks this year? What is causing them? Unfortunately, scientists do not know for sure. There are several well-educated guesses (aka hypotheses) and most believe that there is no single cause of the increased attacks, rather there is a combination of factors…mostly related to food.

Drought through the majority of NC results in decreased runoff into the oceans and increased salinity (saltier water). This may attract more fish, and where the fish go sharks will follow.

shark3_jpeg

Feeding frenzy. Sharks followed fish to shore for dinner.

Warmer water due to an earlier summer can push fish northwards and closer to shore. Again sharks follow their food. Studies have also shown that warm water can make sharks more aggressive. Like us, if they get too hot and uncomfortable, they get cranky!

Sea turtle nesting season is also upon us. This means the little turts are racing towards the waves and struggling out to sea past many predators, including sharks. Their mom’s are also exhausted after laying their eggs and are easier prey as they return to the water. Fishy food = sharks.

Another possibility is that there are simply more people in the water. Tourism along NC coasts are at an all-time high with over 5 million vacationers each summer! With so many people swimming where sharks are, there a bound to be encounters. Usually sharks manage to avoid us.crowded

Below are some more articles about the North Carolina shark attacks and possible reasons behind them:

The Fisheries Blog: Three Things You Should Know About North Carolina Sharks

NPR: Don’t Blame The Sharks For The ‘Perfect Storm’ Of Attacks In North Carolina

IFL Science: Why Have There Been so Many Shark Attacks in North Carolina?

The Guardian: Sharks haunt North Carolina’s Fourth of July, but experts say attacks are rare

Washington Post:  Recent shark attacks, now up to 7 in Carolina’s, puzzle experts and scare beachgoers

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