Looks like a discarded plastic bag? Don’t be fooled – it’s a Portuguese Man o’ War (Physalia physalis). This one washed up on Slapton Sands last week and is one of several jellyfish species that inhabit the waters around the UK. Actually, it is a community of organisms that are named for their resemblance to a frigate.
Jellyfish are predators that start life attached to coastal reefs; their free-swimming medusa phase is the fifth, reproductive stage in their lifecycle. They kill prey using nematocysts – stinging cells usually located in their tentacles. These cells can remain active even when the jellyfish is dead and tentacles that contain the cells can detach from the body and remain lodged in their prey.
The toxicity of the sting varies, but some are powerful enough kill a human and stings can cause an allergic reaction. Dogs that are stung most commonly present with vomiting or retching, oedema (facial, lips, limb, laryngeal) and hypersalivation.
The Veterinary Poisons Information Service advises the following first aid:
- Use a towel or stick to remove tentacles that are attached to the skin but make sure not to rub
- Irrigated the affected area with seawater – not fresh water
- If the area is large and/or the dog is in distress, immerse the affected area in hot water (about 45ºC) for about 20 minutes once the dog is at home
- Get veterinary advice.
Do not rub the area with sand or use urine, meat tenderiser, ammonia or baking soda as they may provoke further discharges of venom.
Keep your dog in sight and under control at all times, train for reliable recall and keep your eyes peeled when out and about on the beach, especially after stormy weather when jellyfish may be more likely to wash ashore.