Invasion of the Velella velella in southern California
MELISSA BLOCK, HOST:
All month long, huge fleets of tiny sailors have been washing up on Southern California beaches. They look like little jellyfish. And in fact, they are somewhat related. But these coin-sized creatures have a distinctive, clear mohawk sticking up from their bodies - a sail, if you will.
JULIANNE KALMAN PASSARELLI: And that's where the common name comes from - by-the-wind sailor.
BLOCK: By-the-wind sailor - or to a biologist, like Julianne Kalman Passarelli...
KALMAN PASSARELLI: The scientific name is Velella velella.
AILSA CHANG, HOST:
Velella velella. Say it with me, Melissa, really, really fast. Velella velella.
BLOCK: Velella velella. Velella...
CHANG: Kalman Passarelli says she's seen those washing ashore lately near the Cabrillo Marine Aquarium, where she works, in San Pedro, Calif. And in addition to the animals' tiny sails, she says their color is striking.
KALMAN PASSARELLI: They're a bright, beautiful blue. And it's thought to be somewhat, like, of a camouflage and maybe even kind of a sunscreen because they're so close to the surface.
BLOCK: Close to the surface because, when they're out at sea, they float on top of the water, sails above the surface, tentacles dangling below. As they bob along, they slurp up plankton that gets tangled in their tentacles.
CHANG: And if you look a little closer, as biologists tend to do, Kalman Passarelli says the Velella velella is truly more than meets the eye. She explained that what looks like a single creature is actually a colony comprised of many different individuals.
KALMAN PASSARELLI: It's a colony of animals. And if you look really closely, all those little things hanging down that look like tentacles are all different organisms within the same colony. And they all work together, kind of like coral, and they all have a different purpose. One is for reproduction. One is for feeding. And one is for defense.
CHANG: A cooperative of sorts, and a reminder that life on Earth is truly weird.
BLOCK: As for why they're showing up on California shores, well, it's their drifter lifestyle.
KALMAN PASSARELLI: They rely hundred percent on the wind and the currents to move them around. They definitely cannot choose where they want to go, hence why they're getting washed up on the beach, right? It takes the right currents and wind to - I guess wrong, for them - to wash them up.
BLOCK: Kalman Passarelli says it usually is a springtime phenomenon.
CHANG: And if you happen to be at the beach and stumble upon a few, don't worry. She says they're mostly harmless, unlike their relatives, the Portuguese man-of-war, though she still advises against touching these tiny, shipwrecked sailors.
(SOUNDBITE OF SONG, "ORINOCO FLOW")
ENYA: (Singing) Sail away, sail away, sail away. Sail away, sail away, sail away. Transcript provided by NPR, Copyright NPR.