Look Out For Blue Sea Dragons Washing Up On Texas Beaches

These little monsters are more toxic than the Portuguese man-of-war.

Beachgoers should watch where they step in Texas. 

Glaucus atlanticus, also known as blue sea dragons, have been known to wash up on area beaches this time of year, posing serious danger to unsuspecting visitors.  

These electric-blue creatures grow to about three centimeters long and are more toxic than even the fearsome Portuguese man-of-war. Members of the nudibranch order, these soft-bodied, hermaphroditic gastropods are part of the sea slug family. 

Blue Sea Dragon

S.Rohrlach/Getty Images

Blue sea dragons live on the surface of the ocean, floating upside down as they’re moved around at the whim of wind and currents. 

“Here in Texas, spring is known for being the windy period,” Jace Tunnell, the reserve director at the University of Texas’s Marine Science Institute, told Texas Monthly. “So, in March and April, when the conditions get just right and you have big waves and strong southeastern winds, that’s how they get pushed up on our shores.” 

Fascinatingly, the sea dragon’s primary food source is the Portuguese man-of-war. This devious little creature uses mucus to neutralize the man-of-war’s infamous stinging cells, steals those cells from its tentacles, and stores them within its own tissue to be released on contact. 

“That’s what makes them so dangerous,” Tunnell explained of the blue sea dragon’s uniquely sourced venom. “It’s concentrated, so it’s even worse than a man-o'-war sting.”

The good news is that blue sea dragons rarely make it to shore. In a 2022 interview with CNN, David Hicks, professor and director of the School of Earth, Environmental, and Marine Sciences at the University of Texas Rio Grande Valley, explained how their delicate constitution tends to keep them from washing up. 

“They are soft-bodied, so they are often broken apart by the time they get through the surf zone and deposited on the shore,” Hicks said.

Blue sea dragon hand


On land, their small size also makes them incredibly hard to see. And, as Tunnell noted, they don’t last long in the sun.

“And once they get up on the sands, if it’s sunny, they dry up real quick, and then you wouldn’t even recognize them,” he told Texas Monthly

If you come across a blue sea dragon while strolling near the waterline, do not touch it. According to Ocean Info, their sting can produce various symptoms including nausea, vomiting, severe pain, redness, papules, and fluid-filled blisters. 

"In very rare cases, there have been people who have died from them,” Tunnell warned. “If you get stung in the right spot, and you’re not someone who can handle a sting, and you have a bad allergic reaction, something bad is going to happen.” 

Go to the hospital if you suspect you have been stung by a blue sea dragon.

Be careful out there, y’all!

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