Global Courant
Scientists monitoring the white shark population in the waters off Cape Cod in Massachusetts are attaching improved sensors, including cameras, to the predators to help scientists track their whereabouts and keep beachgoers informed and safe, researchers said Tuesday.
The program comes just as tourists are filling hotels and rental properties on the Cape for the summer — and white sharks are returning in greater numbers to feed on the region’s abundant seals.
Interactions between white sharks and humans are rare. But the risk is still there. As of 2012, there have been five in Massachusetts — three of them classified as bites, one of which was fatal, said Greg Skomal, the shark expert for the state Division of Marine Fisheries.
“So as a result, we intensified our research off the Cape to study different aspects of white shark behavior,” Skomal said.
For more than a decade, the Fisheries Division and the nonprofit Atlantic White Shark Conservancy have tagged about 300 sharks with acoustic sensors that emit a high-frequency sound to an array of receivers along the coast. Public safety officials and lifeguards are notified when a shark swims within range of an acoustic receiver.
This year, researchers are attaching more camera sensors to the predators.
They capture more than just video. The sensors can detect a shark’s depth, direction, surrounding water temperature, and whether it is speeding up or slowing down. The technology will allow scientists to track the sharks second-by-second, Skomal said.
Megan Winton, a staff scientist at the Atlantic White Shark Conservancy, calls it giving smartphones to sharks.
“They’re equipped with an incredible array of sensors that tell us about the animal’s movements and their environment,” she said, adding that it’s “essentially just riding on the back of a great white shark.”
The information is downloaded to a free app available to the public to reduce encounters and promote safety.
Video captured with a camera tag clipped to a shark’s dorsal fin shows the predator entering the water about 4 feet (1.2 meters) close to shore to chase a seal and blasting a storm of sand from to awaken the soil. The seal eventually escaped.
Sharks are patient hunters.
“They’re slowly patrolling the shoreline very methodically until they essentially have a chance to make their move,” Winton said.
The technology has also provided insight into how curious sharks are. They have been seen coming to the surface to nibble on a lobster buoy or check out a bird or other piece of wreckage, she said.
Researchers have also started using drones to spot sharks from above, a method that has been used in other parts of the world, including Australia, Skomal said.
The downside to the sensor system is that if a shark isn’t tagged, it won’t be detected. But the program does its best to provide information to the public so they can make informed decisions while on the beach.
“We want them to understand these animals and their habits the way we do,” Winton said.
(TagsToTranslate)Fish
