Mysterious-looking sea creatures are making beachgoers double take across Southern California.
They are blue, oval and about 2 to 3 inches long.
The creatures, whose scientific name is Velella Velella, are colloquially called by-the-wind sailors -- thanks to the little sail attached on top.
Experts, who are studying them at the jelly lab of the Aquarium of the Pacific, say by-the-wind-sailors are not true jellyfish although they are related.
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“It’s a jellyfish relative so they’re related to things like sea nettles,” says Wagner. “It’s what we call a hydrazone meaning it has an alternating life cycle.”
The Velella Velellas, which are dependent on the wind and their tiny sails to move around the ocean, show up in big numbers during spring as the ocean warms and produces more bacteria, according to Wagner.
“We get a bacterial bloom which causes lots of nutrients to be in the water and so more nutrients means there more things to eat. If there’s more things to eat, there’s more reproduction,” he says.
The wind then pushes more of them ashore where they lose their blue color and die.
Wagner says although climate change has possibly caused them to show up in larger numbers, their appearance isn’t all that unusual. Still it’s probably not a good idea to pick them up.
“The sting is relatively weak compared to some of the other jellies if you touch it with your hands unless you have an allergic reaction you probably wouldn’t notice," Wagner says. "Any jelly you find at the beach washed up and you think its dead -- its better just to leave it as is because they can still sting.”
Wagner says If you really want to see the by the wind sailors in large numbers and in in their true blue color, go out on a boat, and you’re almost guaranteed to find them.
