By-the-wind sailor

Velella velella · The by-the-wind sailor is a small, deep blue colonial animal that floats on the surface of the open ocean, using a little sail to catch the wind.

Also called Sea raft, Purple sail, Little sail.

By-the-wind sailor
Photo: Joyborg, CC BY-SA 4.0
By-the-wind sailor
Photo: Jymm, Public domain
By-the-wind sailor
Photo: Public domain, CC0

Taxonomy

KingdomAnimalia
PhylumCnidaria
ClassHydrozoa
OrderAnthoathecata
FamilyPorpitidae
GenusVelella
SpeciesVelella velella

Where it lives

Open-sea surface waters worldwide, often stranded en masse on beaches.

Fun facts

  • What looks like one animal is really a colony of hydroids, and most are less than about 7 cm long.
  • Sometimes thousands of them are stranded together on beaches.
  • Some colonies are 'left-handed' and some 'right-handed', which affects which way they drift: in the northern Pacific, one type heads toward North America and the other toward Japan.
  • A single colony can release thousands of tiny jellyfish, each only about 1 mm high and wide, over several weeks.

Play it

The By-the-wind sailor was the creature in a regional daily on November 10, 2026. Can you identify tomorrow's from its photos? Every day brings a new creature to place from kingdom to genus, map and name.

Play today's creature or replay a past daily

Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).