Visitors to California beaches are seeing weird little creatures along the beach in the month of April. So what the heck are these little guys?
Blue-green iridescent sea creatures known as by-the-wind-sailors or Velella velella have been washing up on California beaches in the thousands during the month. These small coin-sized creatures have a transparent, sail-shaped protrusion and a blue-green colouring.
“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 said in a statement. “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.”
While they carry a small toxin, they have little meat and few predators. Sunfish, birds, and turtles sometimes eat them. The mass beachings are not new, having occurred between 2014 and 2016.
According to California State Parks, the creatures have a natural cycle where in spring, strong Pacific winds drive thousands of these creatures from British Columbia all the way to California’s shore. The animals are then either eaten, dry up, or washed back into the sea. During these events, beaches are sometimes covered by several inches of velella turning them blue.
The phenomenon is a result of the creatures being unable to navigate their sail when they are carried inland by the winds. There have been several reported incidents of the creatures washing up on the shores of California this year, and it is not known when they will stop appearing.
Despite the name, by-the-wind-sailors are not actually sailors. They are colonial hydrozoans, which are a type of small jellyfish-like animal. When they are blown on shore, they often create beautiful blue beaches, but people should not pick them up as they can be dangerous. It is essential to leave them alone and let the tides take them back to sea.
These small creatures play a vital role in the ocean ecosystem as they are food for various marine creatures. They also have a symbiotic relationship with a particular type of algae that lives within their tissues. The algae produce sugars from the sun’s energy that the Velella velella can then consume, giving them the energy they need to survive.