If you go to the beach in California or Oregon this week, you may be surprised to find a colorful display.
Beginning in July, millions of small, blue, gelatinous animals have washed onto the sands of the US West Coast.
No, they’re not baby jellyfish. They’re Velella, a different marine-dwelling invertebrate.
Hoards of Velella are an uncommon sight on beaches, especially alive, as they usually cluster just off-shore in springtime, Steve Rumrill, an expert at the Oregon Department of Fish and Wildlife told Reuters.
Growing no bigger than 4 inches across, Velella, live atop the water. Instead of immersing themselves in the sea as jellyfish do, these animals dangle their tentacles down to capture their dinner of tiny marine organisms.
These animals may look a lot like jellyfish, but Jim Watanabe, a lecturer at Stanford University’s Hopkins Marine Station in Pacific Grove, Calif. told the San Francisco Chronicle, that Velella "are as different from jellyfish as mammals and birds would be among vertebrates."
Although the blue creature stings their prey, Dr. Rumrill said their venom isn’t dangerous to humans. But he advises beachgoers to not let their curiosity get the best of them, as the animals’ poison could sting the eyes and mouth.
Velella are commonly known as "by-the-wind sailors," a reference to their nomadic nature. With a stiff sail-like growth sticking up from their flat bodies, the animals are carried across the top of the water as the wind blows. As thin as cellophane, this ridge is likely the reason so many have appeared on beaches this season.
"This is a wind-driven event, and winds are unusual this year," Rumrill told Reuters. As such, experts think climate change may have influenced this mass event.
Further south, however, researchers have other ideas why the Velella are so abundant. Warmer temperatures, of nearly 65 degrees, in Monterey Bay may have attracted the animals, Kate Cummings, a naturalist and co-owner of Blue Ocean Whale Watch in Moss Landing, Calif., told the Santa Cruz Sentinel.
These aren’t the only unusual animals sighted this summer, she said. Long-beaked common dolphins have also frequented these waters.
Velella hadn’t been seen in abundance along the central coast of California in seven or eight years, Nancy Black, Monterey Bay Whale Watch marine biologist and owner, told the Santa Cruz Sentinel.
The tiny blue animals have created another spectacle, as sunfish came to dine. "I’ve never seen a sunfish eating a by-the-wind-sailor in all my 28 years," she said.
But what happens to this marine animal once it’s been stranded on the beach?
Velella can’t live out of the water, Dr. Watanabe explained. Over just a couple hours in the sun, the Velella dry out. With the animals ending up on dry land throughout the past month, many have likely died on the beaches.
But, he said, "If they get washed on shore and the next wave draws them back out, they are probably fine."