
Dangerous animals and plants
When walking in nature outside of Finland, you can encounter insects and plants that are not found here in Finland. Some of these can be dangerous for pets. Below is a brief presentation of plants and insects commonly found in Europe, which pet owners should be aware of.
Portuguese Man O' War
The Portuguese Man o' War (Physalia physalis) is a venomous, jellyfish-like marine organism found in the Atlantic Ocean, including the coastal regions of Europe. While it is most commonly found in tropical and subtropical waters, it is also regularly observed along the coasts of Spain (especially the Canary Islands), Portugal, and western France, and occasionally in the Mediterranean Sea.
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Although it resembles a jellyfish, the Portuguese Man o' War is actually a colonial siphonophore, made up of specialized individual organisms that function together. Its long, bluish-purple gas-filled float can grow up to 30 cm (12 inches) in length, and its venomous tentacles can extend dozens of meters.
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Portuguese Man o' Wars are beautiful but highly toxic to pets. They often wash up on shore after winter storms, and even dead specimens remain venomous.
Portuguese Man O' War at the shore in the Canary Islands.
What If a Pet Comes into Contact with a Portuguese Man o’ War?
​The tentacles of the Portuguese Man o’ War contain nematocysts, which release a powerful neurotoxin. Contact with these tentacles can cause severe pain and serious reactions in both humans and animals. After contact, the skin often develops red, swollen streaks that resemble burns. Symptoms may include intense burning pain, itching, dizziness, and nausea. In severe cases, the toxin can lead to breathing difficulties, heart rhythm disturbances, and even anaphylactic shock.
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For pets, especially dogs, contact with a Portuguese Man o’ War can be extremely dangerous. A dog may step on the tentacles, sniff, or even attempt to bite them, which could result in tentacles attaching to the nose, paws, mouth, or throat. This can cause severe pain, swelling, and breathing difficulties. In the worst cases, the venom can lead to muscle paralysis and anaphylactic shock.
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What to Do If Your Pet Comes into Contact with a Portuguese Man o’ War
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Do not touch the tentacles with bare hands – they can still be active and transfer venom to you.
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Carefully remove the tentacles using tweezers or gloves. Do not rub the affected area, as this can release more venom.
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Rinse with seawater – Do not use fresh water, as it can trigger the nematocysts to release more venom.
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Monitor breathing and overall condition – If your pet shows severe swelling, breathing difficulties, or becomes lethargic, take them to a veterinarian immediately.
How to Protect Yourself and Your Pet?
The best prevention is to avoid areas where Portuguese Man o’ War are present and keep your pet off the beach during their active season. Keep your dog on a leash and avoid walking on the beach, especially after storms, as dead specimens may wash ashore. The tentacles of a Portuguese Man o’ War can remain venomous for several days after detaching from the organism, so caution is necessary even with remains found on the shore.
Pine processionary caterpillar
Pine processionary caterpillar is a nocturnal moth that is found in southern Europe (including Spain, Portugal, Italy, and in its northernmost range, France, Germany, and Hungary). The moth itself only lives for a few days to lay eggs mainly on certain pine trees and does not pose a danger to pets. However, its larvae, which are 1-3cm long, can be life-threatening to pets. The larvae are gray in color with a yellow stripe running along their back. They have light-colored hairs that contain a protein that can irritate the skin of humans and animals. Contact with this protein through skin or mucous membranes can cause mild to severe skin irritation and in extreme cases, even anaphylactic shock. The larvae move in a line attached to each other, and the length of the line can vary from a few larvae to several meters. Dogs and cats are easily attracted to the moving larvae and may easily come into contact with the hairs on their snouts or paws.
Larvae in a typical cotton candy-like nest in a pine tree.
Picture: Health Plan Spain
What if the pet gets catepillar hairs in its skin or mouth?
Caterpillar hairs can stick tightly to the skin, similar to the delicate hairs found on cacti, for example. Anyone who has come into contact with these small spines knows that removing them can be very difficult. If your pet comes into contact with caterpillars, do not attempt to remove the hairs from the skin with your own hands. The hairs are equally painful and dangerous for both humans and pets. It is advisable to rinse the affected area with citrus juice, but water can also be used. The purpose of rinsing is to alleviate skin irritation and remove any remaining hairs. Be cautious while rinsing, ensuring that you do not spray the area with too much pressure and push the hair deeper in the skin or get any remnants of the hairs on your own hands. The use of creams is not recommended as cats and dogs tend to lick them off. However, if the redness on the skin is extensive, your pet may require topical treatments to support healing. The redness should decrease within a few days. Prevent your pet from licking the area by using an Elizabethan collar, as the hairs can cause even necrosis of the tongue, esophagus, and stomach if ingested. If your pet has hairs in its mouth, rinsing can be more challenging. If your pet remains calm, you can try gently rinsing the mouth with citrus juice or a water hose, inserting the hose from the side corner of the mouth and allowing the water to flow downwards towards the front teeth. However, there is a risk of the animal inhaling water if it shakes its head. If your pet has a significant amount of hairs in its mouth or elsewhere on its body, it is likely to be too painful for it to allow the area to be treated. First aid measures should be performed, but especially for pets that have had extensive contact with caterpillars, it is advisable to take them to a veterinarian for necessary treatment. Anaphylactic shock can develop very quickly."
How to protect animals from caterpillars?
Avoid walking with dogs (and cats) in areas where fluffy caterpillar nests are visible in trees. Nests are particularly found in pine trees, but can also be found in other plants. Nests may have also fallen to the ground. Be especially cautious from February to April and keep your dog on a leash in areas where caterpillars are present.