Shark conservation is so successful that researchers are looking for ways to curb human-shark interactions

Shark conservation efforts over the past two decades have been so successful that researchers are testing ways to mitigate human-shark conflicts as populations continue to increase.

Demian Chapman, a senior scientist and director of the Shark Research Center at Mote Marine Laboratory, said sharks are increasingly becoming a nuisance to fishermen because of their predatory or aggressive behavior on their catch. & Sarasota Aquarium.

Chapman told ABC News that a device about the size of a roll of coins that can deter sharks trying to bite fishing lines could be the answer to reducing shark predation and the eventual bycatch of sharks.

The SharkGuard electrical pulse deterrent device is mounted on the fishing line, replacing the sinker, approximately 10 inches from the bait. The device emits shock waves with the intensity of a prank pen, which aggravates the shark’s sensitive pores that detect prey.

“It’s a feeling we don’t have,” Chapman said. “It doesn’t seem to hurt them, but they don’t like the feeling.”

The device is made by a British company called Fishtek Marine, which published a paper in 2022 showing promising results in reducing bycatch in the tuna longline fishery.

Now, researchers at Mote Marine Laboratory Chapman said the aquarium in Sarasota, Florida, is conducting its own testing in its research laboratory equipped with tanks that can hold 60,000 gallons of water, a process that is much cheaper than testing in the field.

When the device is placed in a tank, it can both delay and deter sharks from trying to access the bait, Chapman said. Chapman said that after the initial shock, the sharks sometimes wouldn’t take the bait at all and would “sulk” at the end of the tank.

Tests showed that for sharks that tried again, it took more than twice as long to get hooked.

Chapman said the delay may help fishermen, giving them more time to retrieve the fish before the sharks try again.

So far, researchers have tested small hammerhead and hooded sharks. But Chapman said the goal was to test a wider range of species, including sandbar sharks, which are known for stealing fish.

A 2019 study published in Science found that an estimated 100 million sharks are killed by humans each year. Most of these deaths are due to fishery bycatch.

Management measures taken over the past two decades have allowed shark populations to rebound, Chapman said.

Mote has been conducting shark surveys off the coast of Sarasota since 2003.

In 2021, researchers caught 104 sharks (eight different species) over four days, setting a record for the largest summer catch.

The number of sharks tagged per hour has been increasing over the past 20 years, but Chapman wouldn’t dismiss the increase as overpopulation or infection.

“We don’t know if they’ve reached levels where they’re important to the ecosystem,” he said. “But we do know there are more of them, so we have to learn how to live with them again.”