Has velella velella invaded your favorite fishing grounds or beach? You may not see them at all some years, and all of a sudden you’ll see hundreds of them in the water. Velella jellyfish are small, unusual shaped jellyfish that live on the ocean’s surface.
Identifying Characteristics and Biology
Velella are also called sea raft, by-the-wind sailor, purple sail, and little sail – all names reflecting its unusual sail that is on the top them that can catch the wind and move them over great distances. It is the same little sail that can catch the wind just right and wash many of them on shore at one time, stranding them there. There are many instances of mass strandings of velella on beaches.
They produce a toxin that is venomous, and while relatively harmless to humans, they can sting or at the very least irritate the skin. These jellyfish are asexual and are unlike other jellyfish – they each are their own hydroid colony on the surface of the ocean with individual polyps which feeds it and everyone connected to it ocean plankton and fish they collect. They are a carnivorous animal.
The diagram below, courtesy of jellywatch.org, shows just how different they are from other jellyfish.
Velella Jellyfish Hydroid Illustration courtesy of Jellyfish.org | Dana Point Fish Company
Range and Habitat
Velella jellyfish have what is considered a cosmopolitan distribution, meaning they are found just about everywhere around the world. They live on the surface of the ocean, in warm or temperate waters. Their sails are a disadvantage, though – when the wind is just right it can blow velella right on to the beach by the thousands.
Top and Bottom Views of Velella
Below are different views of the velella, and what they look like on the surface of the water.
Velella Velella (Top View) | Dana Point Fish Company
Velella Velella (Bottom View) | Dana Point Fish Company
Velella Velella on the Surface of the Ocean | Dana Point Fish Company