Fauna
Invertebrate

By-the-wind Sailor

Velella velella

Also known as Sea Raft, Purple Sail, Little Sail

Floating upon the open ocean, this colonial hydrozoan travels entirely at the mercy of the breeze thanks to a stiff, chitinous diagonal sail. Deep cobalt and purple pigments protect its delicate living tissues from harsh solar radiation while providing camouflage against marine predators beneath. Entire armadas drift through temperate and tropical seas, occasionally washing ashore by the millions after prolonged onshore gales.

PelagicColonialMarine
By-the-wind Sailor reference1 / 7
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Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Key facts
Diet & preyFish eggs, Copepods, Zooplankton
Predators
  • Glaucus atlanticus
  • Janthina janthina
  • Ocean Sunfish
ThreatsMarine pollution, microplastic ingestion, and shifting storm patterns
HabitatsNeuston layer of open tropical and temperate oceans
Life spanSeveral months
Classification
  1. FamilyPorpitidae
  2. SpeciesVelella velella
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Harmless to most skin, but avoid touching eyes or mucous membranes after handling.
Responsible observation
  • Beach Encounters: Look for translucent, deep-blue discs stranded in tidelines after heavy onshore winds.
  • Hygiene Precaution: Wash hands thoroughly after touching dried ashore specimens before rubbing your eyes.
  • Sail Angle Observation: Check if the sail runs diagonally left or right, reflecting differing wind-drift orientations.
Related species
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