A summer of horror unfolded on Carolinas beaches last year, when sharks bit eight swimmers at N.C. beaches and eight more in South Carolina as part of a record number of unprovoked attacks worldwide.
Pamela Thompson, who teaches computer science at UNC Charlotte and Catawba College in Salisbury, thinks something good could come from the attacks: A better smartphone app for shark alerts.
Thompson’s specialty is “finding hidden knowledge in the vast amounts of data we collect today.” She set her students to work last summer, amid the Carolinas attacks, and they’re still at it.
Students in Thompson’s Advanced Knowledge Discovery class collected and mined data on weather conditions, water quality, wind speed and direction, moon phases, fish populations – anything that might help explain the attacks.
Catawba College student Christian Watts found last spring that some attacks occurred near sea turtle nests. Four UNCC graduate students continued the work this summer, combing through eight years of data on crab landings and sea turtle nesting to learn about their relationship to shark attacks.
“We are here to study if the onshore movement of turtles and crabs affects the movements of sharks – it might encourage them to come toward shore,” said student Pown Arthi Thimiri Dayasagar.
Interest in alert systems was growing before the record 98 unprovoked attacks, six of them fatal, recorded around the world last year. The U.S. logged 59 of the attacks, with Florida accounting for about half of them. None of last summer’s attacks in the Carolinas were fatal.
Two shark attacks have been reported in North Carolina this year.
Researchers at Duke University and UNC Chapel Hill are testing drones to detect sharks in coastal waters. The nonprofit Ocearch offers online tracking of tagged white sharks and other top predators, including the 3,400-pound Mary Lee that regularly cruises off the Carolinas.
The app reported a six-foot tiger shark being caught July 16 at North Carolina’s North Topsail Beach.
The app has 200,000 users in Australia and recently launched in the United States. It relies on reports from official channels, the public, aerial surveillance and news media but plans to include environmental data, drones and other sources.
“As we launch in America we find ourselves with new opportunities, and aggregating data is one we would like to focus on,” Dorsal’s Sarah Beardmore, a former professional surfer, said by email. “I look forward to the relationship that Dorsal and UNC Charlotte plan to build. I think together we can do some great things!”
With two shark alert apps already in use, Thompson said, “our best contribution will be if we, along with other established researchers, can provide input on the best indicators to monitor and interpret for conditions attractive to sharks.”
Dayasagar and fellow students Sailesh Bhamidipati, Jai Kiran Duvvu and Sonal Kaulkar are also probing Twitter data for shark sightings before attacks. They say a standardized hashtag would help gather sightings data from social media.
Otherwise, “If someone is down the beach and tweets about a shark, how would we know soon enough to make a difference?” Thompson said.
Emergency responders Thompson has contacted on North Carolina’s coast have been encouraging.
“Any effective tools or information that provide important public education can help prevent dangerous interactions with sharks, and ultimately keep beach patrons and rescuers safer,” said Kevin Zorc, fire chief of Nags Head on the Outer Banks. “I commend Pam Thompson’s research team and their interest in this topic, and look forward to future data as it becomes available for real-world use in the field by the community and local emergency managers.”
North Carolina’s coast is rich in sea life, especially where warm water flowing north on the Gulf Stream meets cold water in the southerly Labrador Current. Fish ride the currents. Sharks follow their prey.
Among them are tiger and bull sharks, large species that often figure in attacks on humans. White sharks also pass through on their way to wintering grounds off Florida.
“There are definitely sharks big enough to laugh at our (fishing) gear,” in North Carolina waters, said shark researcher Chuck Bangley, who spoke last week to Thompson’s class.
Most bites in the Carolinas last year were by smaller blacktip and spinner sharks, Bangley said. The attacks came as water temperatures warmed and prey such as turtles and marine mammals moved northward, sharks in pursuit.
Climate change has already altered fish migrations, with some tropical fish already at home off the temperate Carolinas. Some shark species could arrive at the Carolinas coast earlier and leave later in the year.
Bangley, who recently earned his doctorate at East Carolina University, said sharks are intelligent, adaptable and don’t view people as food. Bites are more likely to be cases of mistaken identity, a fluttering hand or leg mistaken for a fish.
Those mistakes can be devastating. In the Carolinas, a 16-year-old boy and a girl, 12, both lost arms.
But Bangley and other experts say the risks are tiny in light of the hundreds of thousands of people who play at the beach each year. It’s still many times more likely, they say, that you’ll die on the drive to the beach.
How to avoid sharks
▪ Avoid the water at night, dawn, or dusk, when sharks are most active.
▪ Avoid water that is being fished, such as at piers, and baitfish indicated by diving birds.
▪ Don't enter the water if bleeding, which sharks can smell and trace to its source.
▪ Don't splash a lot, which can attract sharks.
▪ Use care near sandbars or steep drop-offs, favorite hangouts for sharks.
Source: Florida Museum of Natural History