Jellyfish-like sea creatures wash up on SLO County beaches. Here’s what they are
Thousands of electric blue, jellyfish-like sea creatures have once again washed up on Central Coast beaches this week.
Known by the nickname of by-the-wind sailors, velella velella are hydrozoans — a species related to jellyfish, anemones and corals, according to the U.S. National Park Service.
The oval-shaped creatures are typically 3- to 4-inches long with a translucent, triangular sail attached to it. They eat plankton in the ocean and are blown about the sea by the wind.
Morro Bay Harbor Patrol officer Jeremiah Jacobs said strong northwest winds blow by-the-wind sailors into Morro Bay — a phenomenon he said he notices every spring.
“It’s a natural occurrence,” he said. “It’s not a massive die-off.”
While these sea creatures aren’t generally toxic to humans, some people can be more sensitive to them than others — so Jacobs recommended washing your hands before you touch your mouth or eyes after touching one.
He also advised people to be cautious with their dogs around the velella velella. While some dogs can stomach the sea creatures, others could get sick if they eat one, he said.
This story was originally published April 16, 2026 at 9:00 AM.
