Aquamarine waters and an abundance of marine life make Glover Reef off the coast of Belize a popular diving spot. But soon the azure sky above this barrier reef may be filled with the buzzing of drones, sent to combat the illegal fishing that plagues the region.

An estimated 20 percent of all fish hauled in around the globe are caught illegally, through a combination of fishing in restricted areas, subverting quotas and seasonal limits, and using banned gear. The fish are shipped around the world and sold to existing markets, where most buyers have no idea that the food they are purchasing is stolen goods.

The problem is especially acute in Belize, where hundreds of incidents have been reported over the past few years, according to Julio Maaz, who serves as a fisheries coordinator in Belize with the U.S.-based Wildlife Conservation Society.

In March, the European Union suspended all seafood imports from Belize, Cambodia, and Guinea, saying the countries had not acted forcefully enough to prevent illegal fishing in their waters or by vessels flagged to their countries. (See "Cell Phones Fight Pirate Fishing.")

Belize has only 70 fisheries enforcement officers to patrol its 240 miles (386 kilometers) of Caribbean coast and more than 200 islands. And with fuel prices rising, the enforcement budget has been shrinking. As a result, fishermen get away with flouting the law, says Maaz—especially crews based in nearby Honduras and Guatemala.

But now a new weapon is being tested in the fight against pirate fishing: drones. (See "Pictures: Inaugural Drone Photo Contest.")

Drones Evolve

On June 2 the Wildlife Conservation Society began a pilot project with the U.S.-based nonprofit Conservation Drones and Belize's fisheries department. The first trials have been over the mainland, but soon the team hopes to move operations offshore, to Glover Reef.

The goal, says Maaz, is to increase Belize's ability to enforce its fishing laws by eventually launching a fleet of drones able to look for vessels that are operating in restricted reserves, fishing without the proper permits, or violating quotas or other laws.

Drones, or unmanned aerial vehicles (UAVs), have come a long way in just a few years, says Shah Selbe, a 2013 National Geographic emerging explorer who is conducting his own tests of the technology on the California coast. Drones used to be thought of as "big, scary things associated with war in Afghanistan and Iraq," he says, but now there are many smaller, relatively affordable UAVs being piloted by hobbyists.

Drones are already being employed in a number of civilian applications, including the study of hurricanes, volcanoes, wildlife populations, and wildfires. They are being used to fight looting of archaeological sites, map remote areas, manage farms, and find victims of disasters. (See "5 Surprising Drone Uses.")

Add ocean monitoring to that list. Selbe says he has heard from a number of government agencies and nonprofit organizations that are considering using drones to watch the seas.

How Can Drones Help?

One advantage of using drones to monitor fishing, says Maaz, is that "we have the element of surprise." The devices are so fast and small that it's hard for people to see them coming.

The devices being tested in Belize are Skywalker drones made by Ohio-based Event 38. The fixed-wing, unmanned aircraft have a wingspan of 75 inches (190 centimeters) and length of 51 inches (130 centimeters). They cost $2,400 each on the manufacturer's website.

Currently the UAVs record video that must be downloaded when they're retrieved, although Maaz says he hopes future iterations will be able to stream live video. That's technologically feasible, but the expense is beyond the project's budget.

Through ongoing tests, Maaz hopes Belizean officials will get comfortable flying the machines. He says they have already learned that they capture clearer video if they fly low to the ground.

The team members are also developing safety protocols. They want to make sure the drones won't interfere with traditional aviation.

Once the fisheries officials are ready, they'll begin flying the drones in places where illegal fishing is known to be most prevalent. Their aim is to gather video that will be useful in making arrests. Maaz hopes word of the program will help act as a deterrent.

Drones will be good for monitoring vessels, Selbe says, because they can get close enough to see what people are actually doing, unlike satellites or high-altitude reconnaissance. And they are much cheaper. They will extend the range and stealth of manned boat patrols substantially.

But what if the spies are spotted? "Drones move quickly, and they are small," says Selbe, "so they are pretty hard to shoot down." Still, he notes that he has seen "anti-drone bullets" being marketed by arms dealers, perhaps hinting at conflicts to come.

But "how much does it really matter if one goes down?" he asks. After all, they are relatively cheap, and no human beings are on board. (See "Robot Eyes Protecting From Above: Drones and Ocean Conservation.")

Next Steps

For drones to really take off for conservation, prices need to come down further, says Selbe. And countries need to ease tight legal restrictions on the use of drones for commercial purposes, which the U.S. Federal Aviation Administration is expected to do as early as August.

"When that happens, there will be an influx of new designs and creative solutions that people in conservation will be able to use more readily without having to be technical experts," says Selbe.

Through his Soar Ocean project, Selbe is testing the ability of fixed-wing and quadcopter drones to map the coastline along California and in the Channel Islands National Marine Sanctuary. The work is supported by the National Geographic Society and Lindblad Expeditions.

Selbe's tests have the blessing of the National Oceanic and Atmospheric Administration, which administers the sanctuary. According to spokesperson Vernon Smith, the agency is in the process of "exploring the potential of [drones] for conducting environmental observation missions, including marine life and seabird studies, oceanographic and atmospheric research, and environmental damage assessments."

But, he adds, the agency is not currently pursuing the use of unmanned aircraft for enforcement purposes in U.S. waters.

Back in Belize, Maaz says, "We're hoping other government agencies will be able to learn from what we're doing and be able to embrace the technology to its fullest."