Drones might one day be able to alert swimmers to the presence of sharks in the waters off North Carolina’s coasts. But first, researchers need to know how accurate unmanned aircraft are at spotting sea creatures.
Measuring the drones' accuracy is key to putting the technology to practical use, according to David Johnston, director of the Unoccupied Systems Facility at Duke’s Marine Lab.
“You can imagine if you wanted to try to use this operationally for looking for interaction between people and sharks, you'd want to be confident that if you flew a drone over an area, you would be able to detect a shark if it was there or not,” Johnston said.
Johnston and a team of researchers from UNC-Chapel Hill teamed up to evaluate the drones' potential. They created wooden decoys painted to look like bonnethead sharks, then placed them strategically along intercoastal waterways.
“They're placed in different depths of water, and that allows us to try and understand how deep we might be able to expect to try to see them at different tides,” Johnston said. “It also gives us some information about how well we can see them when the water is murky or when its not.”
The team flew unmanned aircraft overhead to see if the drones could reliably spot the fakes. Johnston said the results have been promising.
“Even when the water is a little murky, we're still able to detect them down to almost a meter or so,” he said. “On clear days, I suspect we'll be able to see perhaps even deeper than that.”
Researchers hope to expand the drone detection method to include other marine species and habitats. In addition to tracking sharks, the technique could be used to locate birds, seals, or sea turtles.