Clemson launches new yellow-legged hornet reporting system

The Clemson University Department of Plant Industry has introduced a new identification and reporting system to help combat the spread of yellow-legged hornets.

The system allows South Carolina residents to report suspected yellow-legged hornet activity and embryo nests as the insects emerge from hibernation in the coming weeks.

Homeowners in select Lowcountry counties, where the hornet is of greatest concern, will receive mailers detailing how to identify the insects and their nests, as well as how to use the reporting system.

Public engagement in reporting yellow-legged hornet activity and nest locations is the No. 1 weapon in protecting South Carolina’s beekeeping industry from potential devastation. We urge Lowcountry residents to check their mail for instructions and use the new reporting system if they suspect yellow-legged hornet activity.

BRAD CAVIN, DIRECTS THE STATE’S RESPONSE TO THE INSECT

How to identify and report yellow-legged hornets

The Clemson University Department of Plant Industry’s Apiary Inspection Program has created a website where South Carolina residents can learn about yellow-legged hornets and report sightings.

The website features details about the hornets, a video tutorial on using the reporting tool and instructions on building a yellow-legged hornet trap.

Residents must submit a photo of the suspected hornet or nest with the report, and nests should be left undisturbed so field inspectors can properly remove them.

“We encourage South Carolina residents, especially those in the Lowcountry, to report suspicious sightings,” Cavin said. “However, we also ask them to visit our website to understand the unique behavior and physical characteristics of yellow-legged hornets. This will help us focus our efforts and avoid using resources on false reports.”

Tracking the spread of the yellow-legged hornet

The first known detection of the hornet in South Carolina was on Nov. 9, 2023. This discovery followed a collaboration between the Apiary Inspection Program and the Clemson Cooperative Extension Apiculture and Pollinator Program, which developed a proactive trapping protocol as an early warning system. A yellow-legged hornet queen was trapped on March 14, 2024.

Currently, the hornet has only been found in Beaufort and Jasper counties. Last year, nests were discovered and removed in Beaufort County, but officials have since expanded trapping efforts to parts of Hampton and Colleton counties.

Recognizing yellow-legged hornets and their nests

Yellow-legged hornets build egg-shaped paper nests above ground, often in trees. In early spring, queens construct small, smooth embryo nests — ranging in size from a ping-pong ball to a tennis ball — in sheltered areas such as eaves or porches. Mature nests can grow large and house an average of 6,000 workers.

Key identification features include:

• Size: Workers are about 25mm long; queens can reach up to 30mm.
• Head: Mostly dark, with a bright orange or yellow front face.
• Thorax: Dark, velvety black or brownish black.
• Abdomen: Dark with a single yellow band near the fourth abdominal segment.
• Legs: Brown or black near the body, with yellow tips.
• Waist: Narrow, where the thorax meets the abdomen.

Yellow-legged hornets can be mistaken for native wasps but can be distinguished by their solid orange face, dark thorax, and yellow legs.

They are also known for their aggressive “hawking” behavior when defending their nests or attacking other bees.

Beekeepers play a vital role

Cavin emphasized the importance of beekeepers in identifying and reporting yellow-legged hornets.

“Beekeepers play a vital role in monitoring their apiaries and reporting hawking behavior,” he said. “Their vigilance is essential for tracking the spread of the hornets and improving response time in locating nests.”

Become a yellow-legged hornet trapper

Yellow-legged hornets by the numbers: 2024 Recap

• 796 traps set in Beaufort and Jasper counties.
• 4,998 trap services completed in those counties.
• 4,219 yellow-legged hornets trapped.
• 16 nests located and removed in Beaufort County.
• 820 citizen reports submitted via the reporting tool across South Carolina and neighboring states.

For the latest information on South Carolina’s fight against the yellow-legged hornet, visit https://blogs.clemson.edu/regulatory/hornet-headlines/.