Texas State Troopers patrol the Rio Grande at the U.S.-Mexico border on August 18, 2016, a corridor long used by drug trafficking vessels. Now autonomous surface vessels, widely known as drone boats, are actively monitoring the area. (Photo by John Moore/Getty Images)
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The Pentagon’s Joint Task Force Southern Border, activated in March of last year, is using autonomous Unmanned Surface Vessels, or USVs, to patrol vast stretches of the Rio Grande to deter drug smugglers.
Also known as drone boats, these vessels are working as security patrols alongside law enforcement and military personnel – with the added advantage of finding blind spots and monitoring areas that are difficult to access.
The Defense Department disclosed that manufacturer Seasats is supply the task force with its solar-powered Lightfish vessels for the Southern Border mission.
A Self-Driving Early Warning System
A contractor operates a Seasats Lightfish, an Unmanned Surface Vehicle (USV), in the Rio Grande river in Texas in January 2026. The USV is solar-powered and used to monitor illegal activity the area. (U.S. Army photo by Spc. Jacob D. Harrell)
U.S. Defense Department
Seasats previously worked with the U.S. Navy to send the Lightfish on a nonstop voyage across the Atlantic to Portugal last year, with the vessel breaking speed records when it reached its destination a just over two months after launching from Florida.
It is now being used to augment U.S. Coast Guard vessels and other military and law enforcement vessels tasked with patrolling the Rio Grande.
Seasats CEO Mike Flanigan said in an interview that the Lightfish is geared towards providing detection and early warning to members of the task force during this mission.
“It’s certainly a challenging environment,” said Flanigan. “When this project was first raised by the Coast Guard, I know there were a lot of USVs in consideration. I have never heard of another USV operating on the Rio Grande, and I think that is because it has a lot of challenges.”
Deterring Smuggling Activity Through Patrols
From left, Gen. Gregory Guillot, commander of U.S. Northern Command, and U.S. Border Patrol watch commander Ruben Garcia look at a tunnel formerly used to traffic illegal drugs across the Rio Grande in Texas in May 2025. Unmanned surface vessels are now being used to deter smugglers. (U.S. Army photo by Sgt. Caleb Woodburn)
U.S. Department of Defense
These challenges include strong currents and obstacles below and above water like logs, roots and dense mud banks. Flanigan explained that the Lightfish’s compact design and ruggedness allow it to operate almost nonstop and without need for supervision.
“I think the reason why you don’t see any other autonomous boats operating in the Rio Grande is that, for these security missions, they only work if the boats can stay out there for weeks or months without maintenance and without support.”
“While we do have support personnel that take care of and maintain the boats, in whole, when these boats are functioning properly they’re out there for long stretches of time untouched.”
The Rio Grande has long been a drug trafficking corridor. A 2007 National Drug Intelligence Center report noted that the river was easily and frequently breached by cross-border drug traffickers often equipped with military-grade weapons, such as assault rifles, which with they often fired at law enforcement.
These smuggling operations saw shipments hauled across the river before being “loaded into waiting vehicles for transport to a stash location or concealed in vegetation until they can be retrieved,” the report stated. Problems with smugglers and comparative lack of U.S. Border Patrol agents compounded the problem for many years.
The task force is now sealing gaps using the Lightfish USVs, which are equipped with cameras, onboard AI and depth sensors.
A Layered Security Network
Coast Guard MSRT members test rubber crafts on the Rio Grande in McAllen, Texas in October 2025 as part of a surge to extend control over approximately 260 miles of the river. (U.S. Coast Guard photo by Petty Officer Third Class Mason Svitenko)
U.S. Coast Guard
Operators can remotely change the speeds at which the vessels operate. The USVs can navigate around obstacles and use their sensors to report activity back to end users.
Their ability to perform continuously while staying unpredictable makes them effective security patrols, Flanigan explained.
“Similar to security guards, it [the Lightfish] can be hard to predict,” he said. “It can cover basically a bigger area more cost-effectively and time-effectively. Rather than single fixed installations that have blind spots, you can cover a wider area.’”
The vessels form part of a layered security network, which includes manned military and law enforcement patrol boats. The autonomous vessels are being used to enhance the reach of the manned patrols.
“One of the benefits of the Lightfish has been that we’ve been able to retask them in partnership with the end users to move them around to places where there’s the most need,” Flanigan said.
As unmanned vehicles proliferate in the air, on land and at sea, their current use by Joint Task Force-Southern Border demonstrates that machines powered by AI can also be used efficiently in confined areas as security guards. It demonstrates that autonomous systems can function as watchdogs in difficult environments. It indicates that drone patrols could be used to enhance a broad range of security systems and expand to private sector use in the future.