Large numbers of jellyfish (Medusas in Spanish) have been a problem from time to time in some Mediterranean beaches during recent years. They tend to arrive in large groups once or twice a season and you need to be prepared in case of a jellyfish sting. On popular beaches a red flag will fly if there are many jellyfish present.
What is a jellyfish?
In English we say jellyfish, but in Spanish it is a Medusa. You really want to avoid the sting of a medusa!
Jellyfish are free-swimming, non-aggressive, gelatinous marine animals surrounded by tentacles. These tentacles are covered with sacs that are filled with poison (venom) that can cause a painful to sometimes life-threatening sting.
Global warming and the decrease in its natural predator, (swordfish and red tuna) is creating ideal conditions for ‘médusas’ or jellyfish to breed. Warm weather has heated up the Mediterranean, meaning that the jellyfish reproduce and mature more quickly. Sea currents and strong winds are responsible for pushing the jellyfish towards the beaches late spring and summer.
Warnings signs of jellyfish in the water
- Red Flags on the beach
- Nobody is IN the water
- Kids and Adults out in the surf with small nets on a pole
- The boat to clean the sea is out patrolling
- Some types of jellyfish have reproductive jelly gatherings 8 to 10 days after a full moon, thus there is an increase in the number of jellyfish found at that time.
Symptoms of a jellyfish sting
- Severe pain
- Headache, nausea, vomiting, diarrhea
- Skin swelling/wounds/redness
- Difficulty breathing, swallowing and speech
- Shivering, sweating
- Irregular pulse/heart failure
- You may get out of the water and see thin red lines on your body, which burn or itch.
What to do if you have a jellyfish sting
- Get out of the water – If you’ve been stung, return to dry land as soon as possible to avoid getting another sting.
- Rinse with salt water – Rinse with salt water and try not touch the affected area with your bare hands. Do Not use cold drinking water, as this will cause more venom to release and thus more pain. Try to remove any visible tentacles with an object other than your hand, with something like a knife or a plastic card.
- Rinse with vinegar – Douse the infected area with vinegar or acetic acid to immediately relieve pain. I know this sounds strange, but a small travel bottle of vinegar should be in your beach bag, right with your sunscreen.
- Hot water – After rinsing the area with sea water, apply hot water or a hot pack “as hot as the patient can tolerate for 20 minutes” or until pain is relieved. This will help stop the venom, so a long hot shower should do the trick.
Seek medical attention
In rare cases of severe stings, one might experience vomiting, trouble walking, nausea, headaches, and seizures. If that’s the case, seek immediate medical attention at the local medical center. In case of an emergency dial 112.
Report your jellyfish sting or medusa sting
Inform the lifeguard on duty (socorrista) or make a report at the local medical center. Whenever possible it is useful to identify the species of jellyfish, perhaps a mobile phone photograph.
Jellyfish on the Spanish Coast
A detailed guide on Mediterranean jellyfish.
Types of jellyfish
While many types of jellyfish are relatively harmless to humans, some can cause severe pain and are more likely to cause a systemic reaction. These jellyfish cause more-serious problems in people:
- Box jellyfish. Box jellyfish can cause intense pain. Life-threatening reactions, although rare, are more common with this type. The more dangerous species of box jellyfish are in the warm waters of the Pacific and Indian oceans.
- Portuguese man of war. Also called bluebottle jellyfish, Portuguese man of war jellyfish live mostly in warmer seas. This type has a blue or purplish gas-filled bubble that keeps it afloat on the water and acts as a sail. In Spring 2018 the beaches along Costa Blanca were closed due to the influx of the Portuguese man of war. Their tentacles are loaded with coiled, barbed tubes that deliver venom capable of paralysing and killing small fish and crustaceans. They are rarely deadly to people but can be dangerous to children, elderly people, asthmatics and people with allergies as they can cause fever, shock and respiratory distress.
- Sea nettle. Common in both warm and cool sea waters, sea nettles live along the northeast coast of the United States and are abundant in the Chesapeake Bay.
- Lion’s mane jellyfish. These are the world’s largest jellyfish, with a body diameter of more than 3 feet (1 meter). They’re most common in cooler, northern regions of the Pacific and Atlantic oceans.
View informative poster with photos of jellyfish.
A detailed guide to the Jellyfish (in Spanish) is published by the regional health department here. InfoMedusa.es is a website in Spanish for the Costa del Sol of Malaga with information and an APP you can download with info and Jellyfish reporting system.