Lovebugs once again filled cities across Korea for weeks this year. Although most have now disappeared, the issue remains unresolved. The number of lovebugs continues to rise annually, yet effective measures have not been implemented to control them. Practical solutions are urgently needed to reduce the risk of recurring outbreaks.

Hikers wave their hands to fend off lovebugs

Photo: Yonhap News (yna.co.kr)

Lovebugs Spread Across the Seoul Metropolitan Area Again

The number of citizen complaints in Seoul about lovebugs has skyrocketed this year. According to the Seoul Metropolitan Government, the number grew from 4,418 cases in 2022 to 5,600 in 2023, then jumped to 9,296 in 2024. In just the first half of this year, more than 4,600 cases have already been reported, indicating that this year could break all previous records.

In recent years, large swarms have been reported in green spaces and mountainous areas such as Gyeyangsan Mountain in Incheon and Inwangsan Mountain in Seoul, causing serious inconvenience to hikers and nearby residents. One visitor to Gyeyangsan Mountain described how lovebugs clung to hats, arms, clothing, and even masks simply by standing on the trail, forcing them to shake the insects off and cut their hike short.

As lovebugs began swarming urban areas in massive numbers, some people even began eating them. In one viral video posted on July 3, a YouTuber who has 1.56 million subscribers collected thousands of lovebugs from Gyeyangsan Mountain and brought them home to cook. The video quickly drew millions of views and sparked a heated debate online.

Why Are Lovebugs Increasing in Numbers?

Lovebugs were not common in Korea just a few years ago. The species Plecia nearctica, commonly known as the lovebug, was first recorded in Korea in 2015, when a few individuals were collected in Incheon. A subsequent collection occurred in 2019, but it was not until 2022 that the insect drew public attention after a large-scale outbreak in Bongsan Mountain, Eunpyeong-gu. Since then, the presence of lovebugs has continued to grow. In 2023, they were spotted in swarms at the summit of Bukhansan Mountain, and in 2024, a major outbreak in Gyeyangsan Mountain in Incheon, again raised concerns. As of this year, their range has expanded even further, reaching Nowon-gu in Seoul and the neighboring city of Guri.

A combination of ecological and environmental factors appears to be behind the recent surge in Korea’s lovebug population. Lovebugs are decomposer insects that lay eggs in soil and feed on leaf litter and organic matter in their larval stage. As adults, they may also serve a partial role in pollination.

Experts say the population is spreading predominantly along green corridors rich in fallen leaves and organic debris. Professor Kim Dong-geon, an ecologist specializing in freshwater ecosystems and pest management at Sahmyook University explained, “The current distribution pattern of lovebugs shows a clear tendency to expand along green zones. The accumulation of leaf litter and organic materials in these areas provides an ideal environment for the insects to lay eggs and grow.”

The explosive outbreaks observed in certain regions can also be attributed to characteristics commonly seen in invasive species. According to Kim, invasive species tend to multiply rapidly in their early stages of settlement because they lack natural predators in the new environment. He noted that “flower bugs like the spotted lanternfly followed a similar pattern when first introduced to Korea—but their population eventually declined once parasitic wasps appeared as natural enemies. In the case of lovebugs, however, that balance has yet to occur.”

He also suggested that the initial discovery in Incheon may be linked to common entry points for invasive species. “Ports and airports often serve as gateways for foreign species, and the fact that lovebugs were first detected in Incheon is likely not a coincidence,” he added.

Firefighters Conducting Lovebug Control Operations

Photo: Yonhap News (yna.co.kr)

The Lovebug Problem: Growing Numbers, Few Answers

However, excessive use of pesticides could make things worse. "Lovebugs are known to possess genetic resistance to pesticides, so excessive chemical use might only strengthen their survival,” Kim warned, urging for environmentally friendly pest control and long-term monitoring as more sustainable solutions.

While lovebugs are not disease-carrying insects, large swarms can still create secondary hygiene problems. Their carcasses may attract rats, flies, and cockroaches, potentially leading to further infestation. There is also a small risk of allergic reactions in individuals sensitive to chitin, a structural protein found in the insect's exoskeleton. In rare cases, accidental ingestion could cause immune responses similar to shellfish allergies.

Lovebugs may have vanished for now, but they are likely to return in even greater numbers next summer. Rather than relying on heavy pesticide use, sustainable control measures based on solid ecological research are needed. It depends on constructive collaboration between public authorities and scientific experts, as well as a broader shift in public attitudes toward urban ecology.