US boosts drone surveillance as flesh-eating screwworms spread in Texas

With the landowner’s permission, the drone teams arrived shortly after sunrise to survey both livestock and wildlife on the ranch. That is because the early morning work hours made it easier for the drone’s infrared sensors to detect warm-blooded animals against the relatively cooler ground.

The USDA is currently researching ways to use AI to “analyze drone imagery to detect wounds, identify animals and prioritize inspections,” according to the department.

Besides using drones for aerial surveillance, USDA has also relied on stationary cameras installed near trails to make more than 26,000 animal observations. It has also established and monitored more than 8,000 fly traps—although there have been no fly trap detections related to screwworm despite the recorded animal cases in the United States.

From detection to eradication

The drones represent “an important force multiplier” for surveying larger numbers of animals in potentially rough terrain but do not replace the “proven eradication method” of releasing sterile male flies to keep down the New World Screwworm fly population in the wild, according to the USDA article.

That method, called Sterile Insect Technique, was originally successful in eradicating flies from the United States and Central America and pushing the screwworm population back beyond the Darién Gap at the border of Panama and Colombia. But the screwworm flies breached the barrier in 2022 and have made their way northward, eventually leading to the new US cases in animals this year.

To combat the spread, the USDA jointly funds and manages a sterile fly production facility with Panama that releases about 100 million sterile flies each week. It also began releasing a similar number of sterile flies per week in Mexico after completing a $21 million renovation to a fruit fly facility in June.

Now that US screwworm cases have appeared, the USDA has been working with the US Army Corps of Engineers to build a new sterile fly production facility at Moore Air Base in South Texas. US Agriculture Secretary Brooke Rollins said that the facility is scheduled for completion by April 1, 2027, according to Border Report.

On July 29, Rollins also announced that the USDA was providing $25 million to build a separate sterile fly facility in Douglas, Arizona. The USDA press release suggested that “construction could be completed in as little as several months.”

The biggest threat that screwworm poses in the US is currently to the livestock industry. But Mexico has already seen over 500 human cases in 2025 and 2026, with a recent study suggesting that the infestation rate is accelerating.

Reporting from Ars Technica contributed to this story.