Seoullo 7017, a former elevated highway in front of Seoul Station that was transformed into a park, has become a popular urban walking destination. It is also known among foreign tourists as a spot for night views. However, what has become more famous than the night view lately is none other than cockroaches. A video posted on social media by a foreign tourist, showing a swarm of cockroaches crawling over a bench, has gone viral and shocked many online. To find out what is happening, I visited Seoullo 7017 myself.

1. The 'Creatures' Crawling Out at Night at a 'K-Night View' Spot
This is what it looks like during the day. You could see people resting peacefully under the shade of trees. I also visited at night, when cockroaches are active in search of food. Even in the early morning hours, when there are fewer people around, cockroaches were still crawling out from various places at the site.

[Lee Min-young & Choi Jun-seo / Gangseo-gu, Seoul: We were just talking about it today. This bridge is full of cockroaches. You wouldn't expect to find them here, since it's high up and on a bridge.]

The cockroaches that have taken over Seoullo 7017 are the Japanese cockroach, also known as the 'house cockroach.' Experts say climate change is the most likely cause.

[Senior Researcher, Korea Pest Control Association: When we look at why this happened suddenly, I think temperature is the number one factor. More broadly, it would be climate conditions. Rising temperatures make it easier for them to overwinter and increase their survival rate. Do they have the potential to thrive outdoors like this? The basic condition is overwintering, and this is a species capable of doing so.]

2. A Cockroach Paradise... Is the 'Cat Mom' to Blame?
However, rumors have been circulating online that the cockroaches might be gathering due to 'cat food' scattered throughout Seoullo. The Seoul Metropolitan Government states that it is not cat food. Since it is an elevated structure, there are no cats, and therefore, so-called 'cat moms' who feed stray cats do not operate there, they explained. However, they believe the food may have been left to feed pigeons, and Seoullo security personnel are patrolling, cleaning up, and conducting awareness campaigns. Perhaps that is why I did not see anything that looked like pet food on the night of June 24, when I visited. Still, if any food is scattered on the walking path, it could affect the breeding of cockroaches.

[Senior Researcher, Korea Pest Control Association: It does help them. However, it is difficult to see this as the sole reason. If basic climate conditions are met and some food is provided, it increases their survival and reproductive rates, acting as a contributing factor, but you cannot say this is the only cause.]

Cockroaches are omnivores that can even eat wood. Since they need protein to reproduce, food scattered on the road can help them multiply. In addition to pet food, food scraps dropped by people while walking can also influence the appearance of cockroaches.

3. Two Rounds of Pest Control, But Is Eradication Difficult?
Immediately after the controversy over the cockroach sightings, the Seoul Metropolitan Government began pest control operations.

[Management Team Leader, Seoullo Management Office: On June 15, the Jung-gu Public Health Center conducted the first round of self-disinfection, and on June 16, a professional company came to diagnose the cause. On June 18, the professional company carried out the first round of pest control.]

When I visited Seoullo 7017, it had been a week since the two rounds of pest control were completed. Does it not show immediate effects after one or two rounds? The Seoul Metropolitan Government explained, "The effects are continuing to appear," and added, "As the number of individuals continues to increase in the summer when temperatures and humidity rise, we are currently working to reduce the population." However, experts say it will be difficult for the cockroaches to disappear completely.

[Dahook / YouTuber specializing in insects and reptiles: If they carry out (pest control) very aggressively, I think the population will decrease significantly. However, the moment that pest control stops, they will increase again. I don't think there will ever be a time in the future where you won't see cockroaches at all.]

[Senior Researcher, Korea Pest Control Association: I think this kind of open space that people use freely is the most difficult to manage. These species even have the ability to defend themselves against natural predators. If ants attack, they can defend themselves by secreting substances from their bodies. That is the reason why they have survived.]

4. Future Tasks?
Marking its 10th year since opening this year, Seoullo 7017 is a landmark visited by over 6 million citizens and tourists annually. As a space used by many, hygiene management is an important task. The Seoul Metropolitan Government announced plans to conduct pest control once a month through October, involving both professional companies and local public health centers, to reduce the population before the winter. Although the management budget for Seoullo 7017 has been cut by nearly half since it was switched to a direct management system by the Seoul Metropolitan Government in 2022, the city explained that this pest control "does not require a separate additional budget, so it is being carried out within the existing budget." With experts diagnosing that it is difficult to completely eliminate the cockroaches, the task ahead is how to manage the landmark so that citizens can visit Seoullo 7017 with peace of mind.

Reported by Jeong Jiyeon | Produced by Shin Heesook | Video by Kim Sang-yoon | Video Editing by Jang Yujin | Graphics by Yang Hyemin | Produced by SBS Digital News