Berlin —
Authorities across Germany are battling an outbreak of poisonous caterpillars that can cause serious health problems, leading to the closure of parks and other outdoor spaces, including in Berlin.
The oak procession moth caterpillars are covered in microscopic barbed hairs that contain toxins that can cause rashes, conjunctivitis, and breathing difficulties when in contact with humans. Toxic hairs can easily break off and be spread over long distances by the wind.
The creature also forms white, silky nests in infested oak trees that are filled with toxic hairs.
The caterpillar infestation is particularly severe in Berlin, with the Charlottenburg-Wilmersdorf, Spandau and Friedrichshain-Kreuzberg districts considered hotspots.
As a result, many of the city’s most popular green spaces resemble crime scenes, with red and white tape warning people to stay away.
In the western district of Spandau, authorities are asking people to avoid the 39-acre local park known as Wilhelm von Siemens Park, as well as adjacent schools, daycare centers and roads, according to the official portal of Berlin’s state and city government.
CNN visited Jungfernheide, Berlin’s second largest park. The park was one of the hardest hit parks in the Charlottenburg-Wilmersdorf district of the city.
Two cherry pickers and seven others wearing full-body blue protective gear, including ventilation masks, were operating vacuum machines of the type designed for asbestos management, sucking out nests from branches about 20 meters (65 feet) above the ground.
These suction cleaners prevent the approximately 700,000 toxic microscopic hairs found in each caterpillar from escaping.
A city official overseeing the work told CNN that 2,000 trees in the park are plagued by encroachment and are off-limits. He acknowledged that there is no way to eradicate the problem. Instead, he said, the aim is to limit damage by having crews tackle the trees closest to the trails used by visitors.
The official said the team was hoping to be able to cut down around 20 trees a day, but added that the level of encroachment varies widely. He said a worker spent a full day over the weekend removing a tree with 800 nests.
Berlin authorities are currently advising people to wash their clothes thoroughly before each visit to a park and to keep windows and doors closed as much as possible.
Other notable outbreaks have been reported in Hamburg and the western German state of North Rhine-Westphalia, according to EPS Radar, a website and digital map that tracks the outbreak.
Britta Wunderwald, the website’s designer, told CNN that she normally works in marketing, but decided to set up the map with the help of AI tools after a visit from a friend’s son who was experiencing symptoms typical of exposure to caterpillars.
“I was wondering if I could go outside and where was a safe place to have a picnic, and then I realized we didn’t have an actual map for this year,” she said in a phone interview.
“I hope next year (Congress) takes it more seriously and acts proactively,” she added.
In a post on the city of Berlin’s website, urban nature expert Derk Ehlert warned people not to approach or touch the caterpillars or their nests. According to Ehlert, more caterpillars have been seen in Berlin this year than usual.
In a post last year on the Berlin Foundation for Nature Conservation’s website, he said the caterpillars originated in southern Europe but were gradually spreading north.
The oak procession moth is especially noticeable in hot, dry weather. The insect has been present in Germany for a long time, but its increasing prevalence is due to climate change and linked to biodiversity loss, according to the EPS Radar website.
In addition to itching and difficulty breathing, touching caterpillar hair can cause allergic reactions such as hives, rash, and in severe cases, anaphylactic shock.
