Pine Processionary Caterpillar - A Dog's Cautionary Tail
Poisonous for pets and mild to sever skin rashes in humans. Find out what the Spanish Pine Processionary Caterpillar is and how to protect pets and humans
Introduction to Pine Processionary Caterpillar
Residents and visitors to Spain need to be aware of the Pine Processionary Caterpillar (Thaumetopoea Pityocampa), known in Spanish as the Oruga Procesionari de Pino, especially if you take pets for walks in parks near cities or go hiking with children and pets, or are near or underneath pine trees which often back the beaches of Spain.
These caterpillars are covered with stinging hairs that can cause mild to severe allergies when they come into contact with human and animal skin. which makes them harmful to young children and adults and sometimes fatal to dogs and cats.
In this article I will explain what Processionary Caterpillar's are, symptoms of a sting, how to avoid them and precautions you should take when in nature in Spain.
What are Pine Processionary Caterpillars
Pine Processionary Caterpillars are usually around three to four centimetres (2 inches) long, with a warm yellow, orange, or brown colour. Their bodies are covered in millions of hairs which function as tiny poison barbs to protect themselves.
They hatch from eggs (normally in Spring) laid in large spiders web like nests that are found clinging between the needle leaves of pine trees. They build a nest which they use as a base while foraging on the pine trees until they are big enough to crawl down the tree to the ground where they form up into a chain (of up to two metres/yards in length) of caterpillars (hence the processionary name) to walk across the ground in search of an underground hide to mature into moths.
Pine Processionary Caterpillars will nest in loose rocks or soil digging themselves down to form cocoons to mature into a moth. Studies of pine processionary caterpillars has shown that they travel long distances at night to feed on pine trees far from their nests, even in freezing temperatures. They also travel during daylight in long chains.
The mature Moth flies out, usually in autumn to eventually fly up in the pine trees and lay their eggs. Each individual moth can lay around 300 eggs in the sticky mass fastened to a pine needles.
The pine processionary caterpillar does not have many predators, but there are a few bird species that enjoy them for a snack and can be a very damaging species for pine forests when the caterpillars consume many of the pine needle leaves.
Habitat of the Processionary Caterpillars in Spain
- Processionary caterpillars can be found in pine forests, or mixed tree forests that have pines, in Spain .
- Coastal (litoral) areas behind beaches and rocky coastline
- Golf courses where there are pine trees
- Lower slopes of mountains where pine forests are abundant
- Private and public gardens and parks with pine trees
Processionary caterpillars are most prolific in spring although can be found from December through to march depending on the temperature. They can also be seen in summer in some high mountain pine forests.
Why are Processionary Caterpillars so Dangerous?
It is when they are in caterpillar format and walking across the ground where they are most dangerous because of their accessibility to humans and pets.
The millions of hairs of the pine processionary caterpillar contain a protein called Thaumetopoein, which in small doses can create a rash on humans that is similar to what you get when stung by a nettle. in extreme cases it can present severe skin rashes and inflammation. The hairs are like darts which detach from the caterpillar to lodge in the victim.
For dogs (and cats) the toxic hairs can cause issues when they come into direct contacts with a nose or tongue and issues when they attach to the animals fur and are ingested while grooming.
- Symptoms to look for on your dog (or if you dog not see it come into direct contact with the caterpillar) are:
- Hypersalivation: One of the first signs of contact with the processionary caterpillar is excessive saliva production. Affected dogs may drool noticeably and suddenly.
- Inflammation of the contact area: The area where the dog has had contact with the caterpillar may become inflamed, red and painful. This inflammation can affect the tongue, lips and other areas of the mouth as well as paws and legs.
- Excessive swallowing: Dogs may exhibit constant swallowing behaviour due to irritation in the mouth and throat caused by the caterpillar toxin.
- Agitation and restlessness: Affected dogs may show signs of nervousness, this could be a response to the physical discomfort they are experiencing.
- Changes in the tongue: The dog's tongue may change color, showing red, purple (cyanosis) or even black hues. This is due to the difficulty in blood flowing normally due to irritation.
- Difficulty closing the mouth: The inflammation caused by the toxin can be so intense that it prevents the dog from closing its mouth properly.
- Ranula: In some cases, irritation in the salivary glands can lead to the formation of a ranula, which is a swelling at the bottom of the mouth due to the accumulation of saliva.
- Difficulty breathing: In more severe situations, swelling in the mouth and throat can cause difficulty breathing, which is a medical emergency.
- Eye problems: If the stinging spines come into contact with the eyes, they can cause blepharitis (inflammation of the eyelids) and corneal ulcers.
- Vomiting: In cases of ingestion of the processionary caterpillar, dogs may experience vomiting and gastrointestinal discomfort, and, in critical situations, systemic symptoms such as hyperthermia, tachypnoea and anaphylactic shock.
Further, the hairs are poisonous even after the caterpillars are dead. If you see lines of them run over by cars on the road they still present a danger to humans and pets so do not tread in them and transport them on the soles of your shoes or let your pet sniff, lick or eat them. The hairs can also be shed when the caterpillars move over the ground.
The potential danger of pine processionary caterpillars should not be underestimated.
Precautions & Protections Against Pine Processionary Caterpillars
When walking in parks and gardens within towns and cities it is most likely that the council will take action to eliminate the caterpillars, although you can never assume that this is the case. In Barcelona the council undertakes measures to control processionary Caterpillars in city parks and gardens.
- Spring: Plastic collars around pine tree trunks prevent the caterpillar from descending from the tree to forage and mature into a moth. The plastic can be filled with water to drown caterpillars.
- Spring and Summer: Sprays and gels applied directly to the procession caterpillars on the ground that kill them.
- Summer and Autumn: light traps for moths. Extermination of the processionary moth and release of non harmful species.
- Summer: Dig around below trees to find and destroy the larvae wearing disposable or washable protective clothes and goggles.
- Early August: spray the trees with bacillus thureingensis, a biological treatment not harmful to humans and pets but produces an enzyme in the gut of the insect that stops its digestion and thus growth of the eggs to caterpillars.
- Precautions that can be taken when walking in pine forests:
- Short leash: Keep the dog on a short leash or to heal and keep a constant eye out for the caterpillars. Steer your dog or child around the procession and avoid contact.
- Be vigilant for nests: Keep an eye out for the nests in the trees because this is a strong indication that you will find them on the tree trunks and the ground.
- Paws and fur: Wash paws when at home to remove any processionary caterpillar hairs. brush out fur to avoid grooming infection.
- Shoes: If you step on the caterpillars, you will have the treads of your footwear full of caterpillar hair. Shoes that you bring home could contaminate your pets environment so hose off your footwear after walks and hikes.
- DO NOT: stomp on the caterpillars or crush them with rocks because this can result in venomous hairs flying in the air which in turn can get stuck on you or anyone around you, including pets.
- Education: Teach children not to touch processionary caterpillars.
- Awareness: Teach children and fellow hikers to call out of they see processionary caterpillars so that others in the group with children or dogs can avoid them.
- Paths: Stay on the hiking path when walking in pine forests.
The only way you can safely protect your dog from pine processionary caterpillars is to avoid taking it to pine forests with nests from the end of December until summer which in many parts if Spain is impossible.
Actions Upon Processionary Caterpillars Contact
- Action to take if your pet comes into direct contact with processionary caterpillars
- Do not rub or touch the affected area: The stinging spines of the processionary caterpillar can release toxins when handled. Avoid touching the affected area with your hands and, especially, avoid rubbing it.
- Clean the mouth and tongue: If you have noticed that your dog has had contact with the caterpillar in its mouth, you can try rinsing its mouth with hot or warm water, since heat helps to deactivate the toxin.
- Prevent your dog from licking the affected area: It is important to prevent your dog from licking or biting the affected area, as this could increase exposure to the toxin.
- Consult a veterinarian immediately: If you suspect contact with the processionary caterpillar, seek veterinary advice immediately. Describe the symptoms and circumstances of the contact so that the veterinarian can offer the best possible advice.
- Don't delay treatment: Speed in administering treatment is crucial. If necessary, your veterinarian may prescribe corticosteroids and antihistamines to reduce inflammation and counteract the effects of the toxin.
- Avoid self-medication: Do not attempt to administer medication to your dog without the supervision of a veterinarian. Treatments and dosages must be specific to each case.
- Observe your dog closely: After contact with the caterpillar, observe your dog closely for any changes in behaviour, appetite, or additional symptoms. If there are any signs of worsening, contact your veterinarian again.
Action to take when a human comes into contact with processionary caterpillars:
Humans can react in different ways to a processionary caterpillar. If you only get a mild reaction with a rash, it can often be enough with an antihistamine cream. But if you swell up, the pain is very strong, or you notice respiratory problems, you should seek a doctor as soon as possible.
If your child gets in touch with the pine processionary caterpillar, make sure you go to a doctor straight away. If the child has touched his or her mouth with an infected hand or put a caterpillar in the mouth, make sure you call the emergency number (122) directly so you can talk to a professional.
Emergencies for Your Pet
Search engine: Veterinario de emergencia en Barcelona para tratamiento de Oruga Procesionaria de Pino
Every pet owner has this list to hand and I am sharing it now with you. Some of the links below also have vet written advice about processionary caterpillars which are worth reading.
- Veterinary Clinics:
- Veterinaria del Mar 24h:
Carrer de Marina 69, 08005 Barcelona +34 900 023 308 - Balmesvet 24h:
Carrer de Balmes 205, 08006 Barcelona +34 931 173 173 - Hospital Veterinari Garbí 24h:
Carretera N-II, km 643 08349 Cabrera de Mar (5 minutes from Mataró) +34 937 591 570 - Vetvida 24h:
Carrer Arcadi Balaguer 89 Bis. Castelldefels. +34 931 747 801 - Hospital Veterinario Montigalà, Badalona 24h:
Passeig Olof Palme 12, 08917 Badalona +34 934 653 434 - Medivet 24h:
Carrer de Cervera 6, 08500 Vic +34 938 852 264 - Dr Patino Veterinary Hospital 24h:
Carrer del Cardenal Vidal i Barraquer 34, 43005 Tarragona +34 977 235 779 - Hospital Veterinari de Lleida 24h:
Carrer Joc de la Bola 16, 25003 Lleida +34 973 280 896 - Hospital Veterinari de Canis 24h:
Can Pau Birol 38, 17006 Girona +34 972 218 668 / Avinguda Lluís Pericot 17, 17003 Girona +34 972 22 7 170 - Hospital Veterinari de Canis 24h:
Avenida Salvador Dalí 13, 17600 Figueres, +34 972 670 179 - TomVets M-F 09:00h-20:30h:
Multiple locations, +34 613 031 871
Elimination From Home or Business
If you find a Processionary caterpillar nest on your property you should not attempt to remove it yourself but contact a professional elimination company.