Battling the Yellow-Legged Threat: Saving Bees from an Invasive Hornet Menace

Jackie Currie, a South Carolina beekeeper with over a decade of experience, observed an unusual and alarming behavior in her honeybee colonies. Instead of actively foraging, her bees huddled nervously at the hive entrance, resembling frightened beachgoers after a predator’s arrival. This paralysis was justified: two yellow-legged hornets lurked nearby, poised to attack.

These invasive predators, native to Southeast Asia, have venomous stings and a unique hunting method. Upon capturing prey, they remove the bee’s head, legs, and wings to consume the nutrient-rich abdomen, leaving entire colonies vulnerable to collapse as resources dwindle.

“It’s heartbreaking because my bees have no defense against these hornets,” Ms. Currie said in June. “Those that know how to combat them are in Asia, not here.” Yellow-legged hornets first appeared in South Carolina’s Lowcountry in late 2023, thriving in the region’s mild climate and abundant bee populations.

Brad Cavin, an apiary inspector with Clemson University’s Department of Plant Industry, leads efforts to track and remove these invasive insects. In 2024, his team identified 16 nests; by late June of the following year, they had already removed 345, a figure that underscores the rapid spread. Mr. Cavin, who regularly travels 250 miles to the Lowcountry from Greenville, likens the mission to a “biblical struggle between good and evil,” often referring to the area as “the Garden of Eden” under siege.

The hornets’ striking appearance—orange faces, large eyes, and yellow legs—belies their stealthy infiltration. They arrived in the U.S. via cargo ships, first detected near Savannah, Georgia, in 2023. With Georgia ranking third in honey production and South Carolina home to 24,000 bee colonies as of 2022, the region offers an ideal habitat for these voracious feeders.

Beyond bees, yellow-legged hornets consume carrion, oyster shells, and even deer remains. The Clemson team focuses on eradicating nests constructed from chewed wood and plant fibers, forming a cement-like paste. These structures, encased in shell-like patterns, grow from Ping-Pong ball-sized embryo nests to basketball-sized secondary nests housing thousands of hornets.

Using a public reporting system, the team has identified nests, though misidentifications with native species like bald-faced hornets and paper wasps are common. To refine tracking, they deploy over 4,300 traps baited with a homemade mixture of grape juice and brown sugar. This year alone, they’ve used 4,100 gallons of grape juice and 9,000 pounds of sugar to lure hornets without harming beneficial insects.

The traps aid researchers in locating nests, as clusters of captured hornets signal proximity. Advanced techniques include marking trapped hornets with colored paint or attaching rice-sized radio tags. Once a nest is found, professionals like Nathan Krelis and Wes Long of Hilton Head Exterminators remove it using beekeeping gear and construction lifts, often facing swarms and deafening buzzes. They seal nest entrances with sponges to minimize pesticide use, then preserve the structures in a kiln for study.

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