Northern Beaches FaunaAustralian Bush Turkey Blue Bottles By-the-wind Sailor Common Brushtail Possum Purple Shore Crab Red-tipped Crab Spider Three-bar Porcupinefish

The By-the-wind Sailor is a monospecific genus of hydrozoa in the Porpitidae family, whose currently only known species is Velella velella. This species is a cosmopolitan free-floating hydrozoan that lives on the surface of the open ocean with the common names of By-The-Wind-Sailor, Sea Raft, Purple Sail, Little Sail, or just Velella.

By-the-wind Sailor (Velella velella), Northern Beaches NSW
By-the-wind Sailor (Velella velella), Northern Beaches NSW

With a world-wide distribution, the By-the-wind Sailor (Velella velella) float on the ocean surface, with short fringing tentacles hanging below in the water. On the ocean, they have a raised transparent “sail” on a blue coloured oval disk that has concentric circles. The float itself is about 4 cm across.

By-the-wind Sailor (Velella velella), Northern Beaches NSW
By-the-wind Sailor (Velella velella), Northern Beaches NSW

Their movement is caused by the wind hitting the sail. As each batch of young vary with a right-hand sail and some with a left-hand sail, this ensures that they do not all get blown in the one direction.

During rough ocean weather, they are found blown onto the beach, often with other creatures such as the Blue Bottles.

Bluebottle Jellyfish (Physalia utriculus) and By-the-wind Sailor (Velella velella), Northern Beaches NSW
By-the-wind Sailor (Velella velella) and Bluebottle Jellyfish (Physalia utriculus), Northern Beaches NSW

  • Scientific Classification
  • Kingdom: Animalia
  • Phylum: Cnidaria
  • Subphylum: Medusozoa
  • Class: Hydrozoa
  • Subclass: Hydroidolina
  • Order: Anthoathecata
  • Suborder: Capitata
  • Family: Porpitidae
  • Genus: Velella
  • Species: Velella velella

Footnote & References

  1. Velella velella (Linnaeus, 1758), By-The-Wind-Sailor, Atlas of Living Australia, https://bie.ala.org.au/species/https://biodiversity.org.au/afd/taxa/f170a621-12cf-42ea-b36a-e2c6bf1201f1
  2. By-the-wind Sailor, Velella velella, Queensland Museum, https://www.qm.qld.gov.au/Explore/Find+out+about/Animals+of+Queensland/Sea+Life/Corals+and+relatives+Cnidaria/Hydrozoans/By-the-wind+Sailor
  3. By-the-wind Sailor, Velella velella (Linnaeus, 1758), Taxonomic Toolkit For Marine Life Of Port Phillip Bay, https://portphillipmarinelife.net.au/species/7759

Northern Beaches FaunaAustralian Bush Turkey Blue Bottles By-the-wind Sailor Common Brushtail Possum Purple Shore Crab Red-tipped Crab Spider Three-bar Porcupinefish

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