"Lovebugs Were Just the Beginning?"... The Identity of the New Pest Spreading Across the Seoul Metropolitan Area

Appearance of "Sudden Pest" Brown Crickets Near the Seoul Metropolitan Area
Resembling Camel Crickets... Caution Needed as They Can Bite Humans

Following the lovebug, brown crickets are now becoming prevalent throughout the Seoul metropolitan area, causing increased inconvenience for residents.

Last year, the peak of Gyeyang Mountain in Gyeyang District, Incheon, was covered with lovebugs (red-backed plant bugs), causing inconvenience to hikers. Yonhap News

According to several online communities on July 4, there have been multiple recent sightings of brown crickets near Bulamsan and Suraksan Mountains in Seoul. After a post appeared in an online community stating, "There are a lot of brown crickets in Namyangju," comments followed such as, "I've never seen them before, but suddenly there are so many this year," "They even come into the house," and "I saw more than 100 on the Bulamsan mountain trail." Namyangju is adjacent to Bulamsan and Suraksan Mountains.

Brown katydid. The Asia Business Daily

The brown cricket is native to Korea and is classified as an 'emergent pest' because a sudden increase in its population can damage crops and cause other problems. Its appearance resembles that of a cockroach. Adult brown crickets are about 3 to 4 centimeters long. Their bodies are brown or dark brown. With strong hind legs, they can jump high. They also have powerful jaws and can bite humans. For this reason, experts recommend that if you encounter a brown cricket, you should not touch it or approach it closely, but keep your distance. In the past, they lived mainly in high mountain areas and were rarely seen, but recently their numbers have increased and their habitats have moved closer to human activity, such as the entrances to hiking trails, leading to greater discomfort for citizens.

Brown katydid and a peach fruit gnawed by the brown katydid that appeared in Yeongdong, Chungbuk. Photo by Yonhap News

Brown crickets have been observed in the Seoul metropolitan area for about two years. The exact cause is not yet clear. Experts suspect it is closely related to temperature changes. A previous study by the Rural Development Administration found that when the temperature increased by 2.5 degrees Celsius, the egg-laying rate of brown crickets rose by 58 to 68 percent. Since their eggs can remain dormant for more than two years, there is also the possibility of sudden mass outbreaks. In the past, brown crickets caused crop damage in Okcheon, Cheongwon, and Boeun in North Chungcheong Province, but recently, sightings have increased around the metropolitan area, indicating an expanding range of activity. Some have pointed out the need to consider control measures, such as natural traps, to prepare for a possible population explosion of brown crickets.

On the other hand, reports about lovebugs (Plecia nearctica) have decreased. According to the Seoul Metropolitan Government, the number of lovebug-related complaints fell from 9,296 cases in 2024 to 5,282 in 2025, and down to 1,515 in 2026. The city believes that preemptive measures—such as controlling larvae, expanding the use of attractant-based traps, and deploying spraying drones—have been partially effective in preventing large-scale outbreaks. Experts speculate that June of this year was less hot than usual, which may have contributed to the decrease in population, and that the pattern of occurrence has shifted from mass outbreaks to a more dispersed distribution. In fact, lovebugs are now being observed at low densities throughout Seoul, as well as in Seongnam, Anyang, and Suwon in Gyeonggi Province.

This content was produced with the assistance of AI translation services.