Creepy, venomous creatures wash ashore in Spanish hotspot

Authorities in southeastern Spain were forced to temporarily shut down a popular stretch of sand earlier this week after two venomous sea creatures known as “blue dragons” were spotted.

The town of Guardamar del Segura, located just north of Torrevieja on Spain’s Mediterranean Costa Blanca, implemented a swimming ban across all beaches after the rare marine animals — scientifically named Glaucus atlanticus — were discovered in the water near Vivers Beach.

“For motives of citizenry safety, we have banned all swimming on all of the municipal beaches until a new order,” the Guardamar police force said in a Facebook post.

Despite its beautiful appearance, the blue dragon is a potentially deadly sort of sea slug.

Measuring just 3 to 4 centimeters in length, these nudibranchs are rarely seen in the Mediterranean and are more commonly found drifting on the surface of tropical and temperate waters in the Atlantic, Pacific and Indian Oceans.

Their vivid blue coloring and wing-like tendrils give them an ethereal look, but their beauty masks a dangerous defense mechanism.

The blue dragon feeds on venomous prey like the Portuguese man o’ war and concentrates their stinging cells in its own tissues. This makes it more venomous than its prey, capable of delivering painful stings that can cause nausea, vomiting, skin irritation, and acute allergic reactions in humans.

Mayor José Luis Sáez confirmed the sightings and quickly issued a red flag warning, closing beaches while a “preventive device” was deployed to monitor the shoreline for more of the creatures.

Swimmers were told to rinse with saltwater and seek medical attention if they experienced stings or skin irritation.

While rare in this part of the world, their appearance is yet another reminder of the increasing unpredictability of marine ecosystems, possibly linked to climate change and shifting ocean currents.

Guardamar del Segura, known for its sunny climate, rocky cliffs, and golden beaches, draws thousands of tourists each year. The sudden beach closures came at the height of the summer season, but local officials say public safety had to take priority.