A drone sent up over the ocean off the California coast is providing more than scenic views: It's giving lifeguards startling insight into just how many sharks circle only feet away from their beach.
A month ago, looking for a more efficient way to detect sharks, Seal Beach in Orange County decided to start using a drone.
"We were looking for a better way to identify the length, and what type of shark, and where they were, so we thought a drone might be useful," Chief Joe Bailey, a Seal Beach lifeguard, told NBC News. "We've been flying it two or three times a week, and it's been a great success at being able to spot the sharks that are near our coastline."
So successful that earlier this week, lifeguards spotted 10 sharks — all juvenile great whites, who don't pose a threat to people — at a time.
"It was nice and calm and the water was clear, and it was really easy to pick them out," Bailey said.
"Everyone knows there's sharks in the ocean. Maybe in years past, we didn't have the technology to see them."
Before implementing the drone, lifeguards had been going out via jet ski in a tedious, hours-long process to look for sharks. Now, they drive the drone to nearby Surfside, launch it, and within 10 minutes, can get a complete look at the area from 100 to 150 feet above the water's surface, Bailey said.
"We can see the shadow of the shark. We'll move down closer, we'll get a close-up, film it if we want," he said.
The film has been shared with shark experts, who identified the sharks as young great whites, all five to six feet long.
Using drones to spot sharks is uncharted waters, said Greg Skomal, a fisheries biologist based in Massachusetts.
In some places, like Australia, trained spotters are sent to the top of cliffs to look for sharks with the naked eye and radio back to the beaches if they see them. Sometimes nets are put up as barriers between swimmers and sharks. And in other places, lifeguards use spotter planes to fly over water.
Another technique is to manually tag sharks so officials can track them as they go up and down the coastline, but that is riskier and may miss a lot of sharks, Skomal added.
"There's problems with almost every technique. There's no silver bullet," he said.
Drones are an innovative idea, but "the smaller drones tend to have very short battery life — 10 to 15 minutes — so you can't keep them up very long," he said. "I"m not quite sure the technology is there yet."
Seal Beach is proving to be a successful test case, though. And the discovery of all the sharks shouldn't send swimmers and surfers into a panic: Juvenile great whites are bottom-feeders, feeding primarily on fish, and are too small to take down seals, sea lions, or — gulp — humans.
"To attack and kill a seal, you've got to have size. You have to have mass, you have to have girth, you have to have weight and speed. That comes as these sharks get bigger and older," Skomal said.
If bigger, more aggressive sharks are seen, the beach will close. But Bailey, the lifeguard chief, said many of the regulars have kept surfing every day since the drone was put into use, despite signs warning of shark sightings.
"Everyone knows there's sharks in the ocean. Maybe in years past, we didn't have the technology to see them. So that's the question now: Is there just more sharks, or is the technology greater to where we're seeing more sharks?" he asked. "It's a great question."