In science fiction, swarms of robots are usually bad news for living things. Just look what happened in The Terminator, or The Matrix. But in the ocean, a growing fleet of autonomous machines are on a friendlier mission. Seafaring ‘bots are helping researchers tackle some of the toughest problems in marine conservation — all while saving boatloads of time and money.
Gliders, as they’re called, are unmanned, safety-yellow robots that can patrol the waves for months on end. Some models look like miniature airplanes, others like surfboards. They come equipped with sensors that can record whale calls, measure water conditions and estimate the abundance of fish and plankton.
Gliders “swim” about as fast as a person walks, but what they lack in speed they make up for in tenacity. The robots chug through hurricanes, high waves and freezing temperatures that would be miserable or dangerous for humans. And even the most-caffeinated scientists can’t match gliders’ ability to work 24/7.
These features are particularly handy for colder seas. Right now, near Newfoundland and Nova Scotia in Canada, two ocean gliders are eavesdropping on whale calls and beaming their recordings back to a land-based lab. Every morning, Kimberley Davies, a whale expert at Dalhousie University, checks the location of the calls on a Google map.
“I can be sitting back and having my morning orange juice, and know that there are right whales in one of these critical habitats,” Davies said. “It’s amazing.”
The right robots for right whales
Gliders do more than just spy on whales. They might also save them.
Collisions with boats are one of the biggest threats to the ocean’s blubbery behemoths. Even though whales are huge, they can be hard to spot from the decks of giant or fast-moving ships. Just a single death can devastate whale populations that have only a few dozen or hundred individuals left.
Boat strikes have been especially catastrophic for critically endangered North Atlantic right whales. These animals live in busy shipping and fishing spots off New York, Boston and southeast Canada. Just this summer, as many as 12 out the remaining 440 died, with several whales confirmed to have perished from ship strikes or fishing gear entanglement.
To combat this, Davies and her colleagues are developing a real-time alert system to let boats know if whales are nearby. Automatic whale alerts would help cargo ships and fishing vessels know where to steer clear of these vanishing giants.
Gliders can listen in on tiny critters as well as enormous ones. Radar-like devices in the robots use echoes to sense the density of small crustaceans, called copepods, that make up the bulk of the right whale diet. Work with “echosounder” sensors helps scientists track trends in copepod abundance and distribution. Understanding what’s happening to the whales’ food will help us better protect them.
Gliders may soon tackle another vexing problem: figuring out how many fish are in the sea. Counting fish is surprisingly expensive. Standard research vessels cost around $50,000 a day. Finding a cheaper, all-weather way to track seafood stocks is something of a holy grail for ocean researchers.
In South Africa, researchers are experimenting with gliders to tally the country’s huge shoals of sardines and anchovies. Rather than counting fish one-by-one, gliders use echosounders to measure fish density. Sebastiaan Swart, an oceanographer involved in these trials, said that the glider’s measurements were comparable to those taken from a ship — a promising sign.
Gliders might even prove more accurate than ships, Swart said. The robots can sample closer to the ocean’s surface than a research vessel can, and because they’re quiet, they don’t scare off fish.
Gliders area also wonderfully cheap. Graham Hine, co-founder of the glider manufacturer Liquid Robotics, says that his company’s robots cost between $1,000 and $2,000 a day, just a fraction of the cost of operating a research vessel.
Their affordability makes gliders “strategically perfect” for lower-income nations that catch huge amounts of fish, but can’t afford traditional ways to count them, Swart said. Accurate fish counts help countries set scientifically informed catch limits, which means that fish can be harvested in a more sustainable way. This is particularly important in places like West Africa or Southeast Asia, where millions of people rely on fish for protein and income.
Gliding into the future
Gliders are just surfacing in the scientific mainstream, said Mark Baumgartner, a glider scientist at the Woods Hole Oceanographic Institution in Massachusetts. But the ‘bots have actually been around for more than a decade. “It’s becoming a much more reliable technology, and it’s being used throughout the world,” Baumgartner said. “This is the future of oceanography, but the future is kind of here now.”
Gliders and other autonomous devices are unlikely to replace manned research vessels, Baumgartner, Davies and Swart agree. But they see big promise in emerging applications for these robots.
For Baumgartner, reconnaissance is a key use. Whale scientists can spend days or weeks on boats chasing down their study subjects — a big investment of time and money. “Now we can send the gliders to look for the whales for us,” Baumgartner said. “That’s an exciting capability.”
These days, gliders usually work solo. Davies and Swart think the robots will work in packs in the future. “I expect in the next five to 10 years we will see small swarms of gliders sampling the coastal marine region, feeding their data directly into databases,” Swart said.
Networks of underwater robots may unmask lingering mysteries about the ocean’s biggest denizens, Davies said. “A fleet of gliders is going to teach us a whole lot about whale habitat and migration patterns,” she said. “We’re at the beginning of what they can do.”