Researchers Matthew Ogburn, left, Charles Bangley and Michelle Edwards tag a juvenile bull shark with an acoustic transmitter. Image credit: Jay Fleming/Smithsonian Environmental Research Center courtesy of NC Sea Grant.
There has been no shortage of sharks spotted off the North Carolina coast this year, and unfortunately, there have been a few attacks. While that may give you pause before entering the ocean, it's not something you think about when swimming in freshwater rivers and lakes.
But at least one WFDD listener has. For this edition of Carolina Curious, a listener asks:
"Is there really such a thing as a North American river shark, and do we have them in North Carolina?"
So the short answer is no, there is no North American river shark specifically. But there is a shark in North American waters that is capable of going up rivers, as well as a couple of different species of stingray. The shark that's capable of going up rivers here in North America is the bull shark. It's actually primarily a Marine shallow water species, but they are capable of tolerating low salinity and even full fresh water.
This species has been found as far up the Mississippi River as southern Illinois. And the record for furthest up river that one of these animals has been caught is actually in Peru. It was caught on a tributary of the Amazon River, so it came in through the Amazon delta and made it almost all the way across South America.
On sharks changing their habits:
The adults have been somewhat regularly sighted in North Carolina for a long time — particularly fishermen will see them especially during the Big Red Drum Run that tends to happen in the late summer into the fall. What seems to be newer in North Carolina is that they're actually using Pamlico Sound as a breeding ground. Juvenile bull sharks weren't commonly caught until about 2011/2012.
Locations of juvenile bull sharks caught in Pamlico Sound by NC Division of Marine Fisheries. Image credit: Charles Bangley.
Probably the spookiest thing about this for me is not necessarily the sharks themselves but the fact that they've changed how they're using the environment. And it mirrors a trend that we're seeing along the entire coast. With warming ocean temperatures you're getting species shifting north and using habitats differently than they used to.
On shark concerns:
So far this summer in North Carolina we're about one bite on a person above average. North Carolina typically averages about one to two per summer. And usually they're not generally bull sharks. They're usually species like black tip sharks or spinner sharks that leave a relatively minor injury that typically requires stitches but isn't usually life threatening. When there's more damage it's usually something larger like a bull shark or a tiger shark. We've had at least one bite this summer that was more than likely one of those.
Whether or not the prevalence of more sharks in the water actually increases the likelihood of getting bitten is still something that's kind of up for debate. If they really wanted to prey on us there would be bites a lot more often. And it seems to be, compared with the number of people in the water and the number of sharks in the water, an actual bite on a person — the odds are pretty low.
