By-the-wind-sailor

Description:

These were 2cm Velella. They can get bigger, but none on this beach were any larger than 3cm. They are a beautiful blue disk with a completely clear "sail."

Habitat:

Velella live in huge congregates on the open ocean. When wind and current conditions allow, they wash up on shore in the hundreds or thousands where I'm pretty sure they die.

Notes:

They have tentacles (which I couldn't see) that trap and poison their fish-fry prey. "They are not individual animals but a colony of polyps that specialize in certain biological functions." (National Marine Sanctuary Foundation web site). When I've seen pictures of these creatures I always imagined they were about a foot long, but they are quite tiny. And you can see why marine animals ingest so much plastic; some of their natural prey (Velella) look just like plastic.