Don't Touch! Why These Beautiful Blue Dragons Are Closing Spain's Beaches

The "blue dragons" that have caused beach closures in Spain are not mythical creatures, but rather a species of small, venomous sea slug scientifically known as Glaucus atlanticus. Also referred to as blue angels, sea swallows, or blue sea slugs, these mollusks are known for their striking appearance and potent sting.

(Photo Credit: Wikimedia Commons) Why These Beautiful Blue Dragons Are Closing Spain's Beaches

What Are Blue Dragons? Key Characteristics:

Appearance: Blue dragons are small, typically growing to a maximum of 3-4 centimeters (about 1.2 inches) in length. They have an elongated body with six distinctive, feathery, finger-like appendages called cerata. Their coloration is a brilliant example of countershading: their underside is a vivid blue, which helps them camouflage with the ocean's surface from above, while their back is a silvery-gray color that blends with the bright surface of the water when viewed from below.

Habitat and Lifestyle: Unlike most sea slugs, which live on the seabed, blue dragons are pelagic, meaning they live on the open ocean surface. They stay afloat by swallowing and maintaining an air bubble in their stomach. They drift upside down with ocean currents and winds, leading a passive, nomadic lifestyle.

Diet and Venom: This is the most crucial characteristic that makes them a danger to humans. Blue dragons are carnivorous predators that feed on other venomous marine animals, including the Portuguese man o' war (Physalia physalis). They are immune to the venom of their prey and have a remarkable ability to ingest and store the stinging cells (nematocysts) in their own cerata. The blue dragon concentrates these stinging cells, making its own sting more powerful and dangerous than that of the creatures it preys on.

Why have they led to beach closures in Spain?

The recent beach closures in Spain, particularly along the Costa Blanca in Alicante and other areas like Cadiz, Valencia, and Lanzarote, are a result of an unusually high number of blue dragons washing ashore.

Uncommon Occurrence: Blue dragons are typically found in the tropical and temperate waters of the Atlantic, Pacific, and Indian Oceans. While they have been sighted in the Mediterranean Sea before, it is a rare event. The recent "massive appearance" of these creatures, sometimes forming large groups known as a "blue fleet," is highly unusual and has been linked by marine experts to factors like shifting ocean currents and rising sea temperatures, possibly due to climate change.

The Danger of Their Sting: The presence of blue dragons on tourist-friendly beaches poses a significant health risk. When a human touches a blue dragon, the concentrated stinging cells stored in its appendages are released. The sting is described as extremely painful and can cause a range of symptoms, including:

Intense pain

Skin redness and swelling

Nausea and vomiting

An acute allergic reaction (dermatitis)

In severe, albeit rare, cases, a life-threatening anaphylactic shock is possible.

Persistent Threat: The danger of a blue dragon sting does not end when the creature is out of the water. Its venom remains active even after the animal has died or been stranded on the sand. This means that people, especially curious children, who might be tempted to pick up or step on the small, beautiful creatures are at risk.

Protocol and Public Safety: Local authorities in Spain have been forced to take immediate action to ensure public safety. They have raised red flags and temporarily banned swimming and beach access in affected areas. The public has been warned not to touch the animals, even with gloves, and to seek medical attention if stung. First aid for a sting typically involves rinsing the affected area with saltwater and applying hot water to deactivate the toxins and alleviate pain.