A video was posted on facebook presenting some very beautiful, flowing creatures in dark waters. The amateur videographer had apparently shot it in Jolly Harbour and was asking local marine experts what they thought these unique creatures are.

Man-of-the-sea / eco activist Eli Fuller and others quickly tagged the video as showing Box Jellyfish or Sea Wasp. There are definitely jellyfish that pose a danger to humans, floating around in the waters of Antigua and the Sea Wasp definitely packs a sting.

Sea Wasps and Box Jellyfish in the Caribbean have potent venom but are not known to be deadly. (Australian Box Jellyfix are a different story). While they vary in size, they are a bell-shaped body which is approximately 2-3 inches in size; with four tentacles that trail behind it. The tentacles are the dangerous part of the jellyfish and what packs the sting. Tentacles have many tiny stingers known as nematocysts which behave like tiny syringes, injecting toxins into the flesh of anything the tentacles touch (stinging and digesting sea creatures is how they eat).

Jellyfish is more common in the spring and Sea Wasps are most prolific when they 'swarm' in the summer after full moons, while spawning.

Prevention

Strong currents bring jellyfish close to shore, mostly in the spring time.

Wet suits are the best protection from stinging tentacles or even snug fitting t-shirt helps. Both also protect (more and less) from sun exposure. Never touch any jellyfish's tentacles or even separated tentacles; even a dead one washed up on shore. Dead jellyfish can remain potent for up to days after.

Symptoms of a sting

Beyond the initial pain, there are other symptoms that come with being stung by a Box Jellyfish / Sea Wasp. Welts and angry red swelling are visible to the eye. The pain should fade within 24 hrs. Nausea, vomiting, shortness of breath, low blood pressure and muscle spasms are also symptoms that may occur. If breathing becomes difficult, seek immediate medical attention.

Treatment for stings

Contact with stinging jellyfish tentacles can appear as a rash, blisters and often in a line. Do not scratch. Do not pee on it either. Apply vinegar PRIOR to removal of tentacles. Vinegar will neutralize the nematocysts. Vinegar AND talcum powder is even better. (Be advised. Vinegar is not the appropriate treatment for the Portuguese Man O War.) Then, with a glove, towel or by scraping with a shell carefully remove any remnants of tentacle that remain stuck. Washing off with salt water will help. Do not shower or bath in fresh water as fresh water triggers the stinging cells. Antihistamine can help. Depending on the severity, consult a medical professional.

All this said, don't worry too much about being stung by jellyfish in the Caribbean. Most stings are very minor. The intensity of the sun is a much greater danger for snorkelers and swimming in the Caribbean.