Bizarre, iridescent sea creatures have been washing up by the thousands on beaches across California throughout the month of April.
The critters – small, coin-sized creatures with blue-green colouring and a transparent, sail-shaped protrusion – are Velella velella, known as by-the-wind-sailors, according to California State Parks.
“Don’t worry about those little blue tentacles that hang from their body! These tentacles don’t sting humans but will gather up plenty of zooplankton or fish eggs for them to eat,” Point Reyes National Seashore wrote on Facebook earlier this month. “You may come across a fresh wash-up of Velella, tinging the stretch of shoreline blue, but if they’ve been there a while, they will look like crinkly and dry ovals of cellophane.”
Others said more caution was warranted.
“If you were to touch the top of the sail, it feels like plastic. It’s quite thick. And actually what’s in there is chitin. And that’s the same material that is in the exoskeleton of crustaceans. So it’s notoriously hard and protective, but you definitely don’t want to pick them up and touch them because they are cnidarians,” Marine biologist Julianne Kalman Passarelli told NPR. “Their sting is not known to be as toxic as their relatives, the Portuguese man o’ war, or even their more distant relatives jellyfish, sea nettles, things like that. But they can cause irritation. I wouldn’t suggest picking them up with your bare hands.”
The Velella velella have been spotted onshore across the state, including in Hunting Beach, Zuma Beach, Manhattan Beach, Salt Creek Beach.
Previous mass beachings have occurred between 2014 and 2016, according to the Orange County Register.
The tiny sailors carry a small toxin and have little meat, so they have few predators, though sunfish, birds, and turtles sometimes eat them.
“They’re amazing animals. They’re like space aliens or something that have invaded our beaches, but they’re not going to be here for very long,” Bruno Pernet, a professor of biological sciences at California State University Long Beach, told KTLA.
Once they come on land, the beached animals are either eaten, dry up, or get washed back into the sea.
What’s driving the sudden blue masses appearing on California beaches?
“In spring, shifting strong Pacific winds often drive thousands of these creatures on shore from British Columbia all the way to California,” Point Reyes public information officer Christine Beekman told the San Francisco Chronicle. “Sometimes beaches are covered by several inches of velella turning the beaches blue.”