Processionary Moths in Mallorca: How Dangerous Are the Caterpillars for People and Dogs?

Processionary Moths in Mallorca: How Dangerous Are the Caterpillars for People and Dogs?

Key question: Are the current measures sufficient, or do we need a more planned approach to protect people, pets and green spaces?

Since mid-February, the hairy nests of the pine processionary moth (Thaumetopoea pityocampa) have been appearing in pine forests, parks and even suburban gardens. The small but insidious threat is not new: the fine stinging hairs cause skin rashes, irritating coughs and sometimes eye or respiratory problems in humans. For dogs, a simple sniff can be dangerous; swelling in the mouth, severe pain or even shock are possible. Authorities urge caution and recommend seeking immediate medical or veterinary help if symptoms occur.

There are initial measures on the island: in the municipality of Calvià, so-called noise cartridges are to be used until February 28 with the aim of dislodging nests from the trees. The idea is practical: the nests fall and are then collected. But the bang is not the only option — and it raises questions.

A small reality check: what works and what does not? Noise cartridges can indeed dislodge nests, but the fine hairs remain in branches, cones and in the soil. They are easily stirred into the air and remain irritating for a long time. In addition, the loud bangs cause stress for wildlife and residents; noise is not a welcome method in busy residential areas. Other often effective methods are targeted removal by professionals wearing protective clothing, vacuuming the nests, or using biological insecticides such as Bacillus thuringiensis at a specific larval stage. Some municipalities are using pheromone traps or precisely timed biological measures to minimize harm to farm and wild animals, as Llucmajor has expanded protection measures against the oak processionary shows.

What is missing from the public discussion? First: transparent information about where exactly measures are being taken. For residents and dog owners, a map of treated areas or at least regular updates in several languages would be helpful. Second: clear rules of conduct for recreational users — families with children, people with strollers, cyclists and dog owners need practical recommendations rather than vague warnings. Third: disposal concepts for fallen nests; discarded remains on green verges remain dangerous.

An everyday scenario from Palma: it is a mild February morning at Castell de Bellver. Joggers circle among the pines, school classes head toward the old town, dog owners walk on leashes with their eyes on the ground. Nobody wants to be suddenly confronted with itchy skin or an injured animal. This is where information signs, barriers and alternative routes must be visible — not only in the press release, but at the park gate, at the park exit and at the corner café.

Concrete, immediately implementable proposals:

1) Transparent map and multilingual information: Municipalities should display online and at central points which areas have been treated and which routes should be avoided. Information in German, English and Spanish reaches both tourists and residents.

2) Targeted removal by teams: Train special response teams with protective clothing, vacuum equipment and secure collection containers. Vacuuming nests significantly reduces stinging hairs in the area.

3) Prioritize animal health: Inform veterinarians early and create emergency guidelines for dog owners (e.g. do not remove anything from the mouth, rinse immediately, prepare the animal for transport).

4) Gentler biological options and timed action: Where possible, use biological agents at the appropriate larval stage instead of blanket noise operations. Pheromone traps at sensitive sites can also help.

5) Public education: Flyers at parks, schools and dog clubs: how to remove hairs (for example with adhesive tape), how to clean after contact, and when medical help is necessary.

A pragmatic approach is possible: combined measures, clear communication and consideration for animals and nature. At warning signs of severe reaction, affected persons should seek medical help immediately; the same applies to pets at the vet. Panic does not help — well-informed caution does.

Conclusion: The processionary caterpillar is back this year; it is unpleasant, but manageable. Instead of relying solely on loud bangs, we need a plan with mapping, gentle removal, clear signage in places like Bellver or urban green spaces and practical recommendations for dog owners. This can significantly reduce the risk for people and animals — without unnecessary noise and without nests ending up scattered in neighbors' gardens.