If you’ve been to the beach recently, you’ve probably noticed abnormally large amounts of odd, blue creatures resembling jellyfish washed up on shore. These mysterious creatures are Velella velella (Velella), or “by-the-wind sailors.”
Contrary to popular belief, Velella are not jellyfish, though they are closely related to them. Velella are actually a cosmopolitan free-floating hydrozoan related to sea anemones and corals, cosmopolitan meaning wide-spread or adaptable. They are only around 1.5 to three inches in size, with a bright blue oval-shaped body and clear “sail” attached to the top, as well as short, stinging tentacles which they use to capture prey. Their sails allow them to catch the wind and travel along the currents as they drift across the open ocean.
Each year with the arrival of spring, the little blue Velella wash up onshore across the coast of California thanks to windy conditions and upwelling. Upwelling occurs “when winds push surface water away from the shore and deeper water rises to fill the gap,” according to the National Oceanic and Atmospheric Administration (NOAA). Because the Velella have no locomotion, the changing wind and current patterns of the ocean force them to wash up onshore, where they are unable to survive. When they dry in the sun, their tissues decompose and their bright blue color fades to transparency.
The last two years in particular have seen a spike in sightings of the Velella according to the Los Angeles Times, but so far it is unclear whether this accurately reflects an increase of the velella’s numbers. Prior research has also shown that the increase in beached Velella may be linked with the increase of high ocean temperatures and climate change.
The presence of Velella velella is not dangerous and poses little threat to humans, though it is advised not to touch them to avoid irritation from their stingers. Though they may seem like a hindrance or eyesore, beaches full of these odd-looking creatures gives us an opportunity to explore more about their species while also offering us further insight into the deep mysteries of the ocean.
