SANTA CRUZ — Helpless in the wind and sounding like a nominee for Best Foreign Language Film, velella velellas have returned to the Monterey Bay in droves.

Strikingly blue and about the size of a hand, the small marine invertebrates main feature is a curved, cellophane-like sail that makes them vulnerable to the whims of stiff breezes that can leave them stranded onshore by the thousands. They began showing up over the weekend, like flotillas of tiny, delicate rafts.

“I’ve seen them in years past up on Bonny Doon, Davenport Beach, but I’ve never seen them alive before. They’re really cute, they just kind of sail out there,” said Jodi Frediani, a local photographer.

Once common and often lumped in with true jellyfish, they are also known as “by-the-wind-sailors” but seem to have disappeared from the Central Coast over the past seven to eight years. They are back this year, playing a minor part in the summer’s aquatic show, which is headlined by frisky humpback whales.

Monterey Bay Whale Watch marine biologist and owner Nancy Black said they always used to show up in the spring, but started returning over the past weekend.

“It’s been eight years, plus or minus, that we’ve seen them,” Black said. “Why they’ve come now, it’s hard to say.”

Kate Cummings, a naturalist and co-owner of Blue Ocean Whale Watch in Moss Landing, said they’re starting to wash up at beaches there and at Asilomar State Beach. She speculated warmer ocean temperatures — water temperatures in Monterey Bay are nearing 65 degrees — are behind their return.

“By Sunday afternoon we were seeing hundreds of them grouped together,” Cummings said.

Warmer water is bringing other unusual sights, including more sightings of long-beaked common dolphins, Cummings said. Black said she’s also seeing more Risso’s dolphins, joining the bay’s resident Pacific white-sided dolphin, which prefers cooler temperatures.

Black also has seen another odd sight: sunfish, or mola molas, have been gobbling up velella velellas (which is a mouthful, so to speak).

“I’ve never seen a sunfish eating a by-the-wind-sailor in all my 28 years,” Black said.

Because they exist at the surface of the water, velella velellas are often lumped in with Portuguese man o’ wars, a creature known for long tentacles and painful stings. While velella velellas sting and are toxic to their prey, they are harmless to humans, though it’s not recommended that you touch them.

Man o’ wars are actually colonies made up of several organisms, each serving a specific purpose. New research suggest velella velellas are actually unique organisms, however. —— (c)2014 the Santa Cruz Sentinel (Scotts Valley, Calif.) Visit the Santa Cruz Sentinel (Scotts Valley, Calif.) at www.santacruzsentinel.com