article_detail

 

With summer now in full swing and many of us heading to the coast to escape the heat, beachgoers are being warned to watch out for an increasing number of jellyfish and their lookalikes drifting into Spanish waters.

 

Experts say the rise in sightings of jellyfish, including the common Pelagia noctiluca, often called the mauve stinger, is linked to disruptions in the marine ecosystem caused by climate change and human activity. According to Ricardo Aguilar, expedition director for the marine conservation group Oceana, warmer sea temperatures, increased ocean pollution and a drop in natural predators such as loggerhead turtles and bluefin tuna are all fuelling the surge in numbers.

 

“These species reproduce more in warmer water,” Aguilar explained. “We’re seeing fewer predators due to overfishing, and more jellyfish as a result.”

 

Although some jellyfish are more of a nuisance than a threat, others can pose serious health risks. The Portuguese man-of-war (Physalia physalis), often mistaken for a jellyfish, is particularly dangerous. It isn’t a true jellyfish but a colony of polyps that float together, with long tentacles that can deliver a powerful sting.

 

In rare cases, the sting from a man-of-war can be fatal, especially for people who are allergic or have a low resistance to the toxin. “It can cause death if the person is allergic,” said Aguilar, adding that even detached tentacles can remain active for hours after washing ashore.

 

While jellyfish such as the fried egg (Cotylorhiza tuberculata), common jellyfish (Aurelia aurita) and the barrel jellyfish (Rhizostoma pulmo) have also increased in number in recent years, they are generally less harmful as they lack the ability to pierce human skin.

 

Aguilar said their arrival on the coast depends largely on ocean currents and wind patterns, which are being increasingly influenced by climate shifts. The coastlines of Andalucía and the Balearic Islands tend to see the highest numbers due to their location along major biological corridors, particularly the Strait of Gibraltar. However, sightings along the Atlantic coast aren’t uncommon.

 

The growing presence of jellyfish and similar marine species has led to the popularity of crowd-sourced tools like MedusApp, which lets swimmers report sightings and stings in real time. The data helps researchers monitor jellyfish activity and better understand their movements.

 

Last October, a British inventor also made headlines for developing a new tool to treat jellyfish stings more effectively. Mark Dyer’s Stingblade, inspired by a diver’s knife, works by gently scraping venom and stingers from the skin, giving beachgoers quick relief without the need for vinegar, hot water or other DIY tricks, including the widely believed but false idea of urinating on the wound. The plastic device doesn’t rust or cut the skin, making it safe to use straight from the beach bag. Better still, it’s made from recycled fishing nets, helping clean up the sea at the same time (based on October 2024 article on jellyfish sting app and treatment innovation).

 

Whether using a tool like Stingblade or not, the basic first aid advice remains the same. Aguilar recommends rinsing the area with seawater rather than fresh water, which could trigger further stinging. “Don’t try homemade remedies,” he said. “They could make it worse.” Any remaining tentacles should be carefully removed, and applying something cold can help reduce swelling. In more serious cases, such as when someone feels nauseous or struggles to breathe, it’s essential to seek medical help straight away.

 

Although many stings are mild and manageable, for some, especially older beachgoers or those with health issues, the effects can be more serious. “It’s a bit like a bee sting. Some people hardly notice it, others can have a strong reaction,” said Aguilar.

 

So while a dip in the sea is still one of the best ways to cool off this summer, it’s worth keeping one eye on the water.

 

 

Image: Pexels/Pixabay