10 cool things about the blue dragon sea slug

There is no doubt that the blue dragon sea slug is a beautiful creature with amazing colours. Here are the top ten cool things about this dragon.

  1. An ancient sea god
    The blue dragon was first discovered by a scientist named Forster over 242 years ago, in 1777. He named the strange creature Glaucus atlanticus after the Greek sea god Glaucus, who was said to have eaten a magical herb that made him immortal.

2. Topsy-turvy
The blue dragon swallows air bubbles that allow him to float at the ocean’s surface, alerting us to his presence. He has a little air-filled sac in his stomach that makes him float upside down. So the interesting blue-and-white colour patterns we see are actually on the bottom side of the blue dragon, not the top.

3. Can you spot him?
Countershading is a defense mechanism used by animals where the top and undersides of their bodies are two different colours. The blue dragon uses this technique as a form of camouflage. The bottom side (abdomen) is a deep blue with white stripes to mirror the colour of the waves so that predators from above can’t see him well. The top of his body is a light grey that camouflages him from predators below, blending in with the reflection of the sky.

4. Caution: poisonous 
He can absorb toxic chemicals from his prey by eating their nematocyst, which is a stinger cell where the poison is stored. The toxin is stored in the finger-like tentacles on the sides of his body, which are called cerata, and when released is potent and dangerous.

5. Immune to stinging
Because of the toxicity of his prey, the blue dragon has a defense mechanism of his own. He has a hard disk underneath his skin, surrounded by a protective layer of mucus, that makes him immune to the stinger cells of his prey.

6.  No separate gender
Like most sea slugs, the blue dragon is hermaphroditic, which means that he can produce both eggs and sperm, but requires a mate to fertilise the eggs. Once fertilised, a string of eggs is released and can sometimes contain 36 to 96 eggs in them. This creature lays eggs in driftwood or in the carcasses of his prey.

7. Beware of teeth
The blue dragon has a jaw and a set of teeth that allows him to grip and remove chunks off his prey. His favourite food is the Portuguese man-o-war, more commonly referred to as bluebottles. The blue dragon eats the bluebottle by chewing off chunks.

8. On our beaches
The blue dragon lives in tropical oceans like the Pacific, Atlantic and Indian oceans. South Africa falls between the Atlantic and Indian Ocean, which means that he can be found in the eastern and southern coasts of South Africa. Blue dragons have also been found in oceans in Europe, Australia and Mozambique.

9. Tiny and dangerous
While potentially dangerous, blue dragons can only grow up to 3cm in length. They live between one month and one year, which is the standard lifespan of sea slugs.

10. A powerful sting  
The blue dragon’s sting has similar symptoms to that of the bluebottle because of the way he absorbs his prey’s toxins. His sting is so powerful that it overcomes prey larger than himself. If the blue dragon feels threatened, he will release the toxin he’s stored up, resulting in a painful sting that can last up to an hour, and even blisters and scarring in rare cases. In extreme cases, where someone has a severe allergic reaction to the sting, and because of how concentrated the toxin is, the blue dragon can kill a person. So while they’re pretty to look at, don’t pick them up. Remember what they say about dynamite coming in small packages, and admire these beautiful creatures from afar.