May 14 2010 -- Aug 15 2010 Watch for By-the-wind Sailors Stranded on Our Shores
Photo by Molly Morgan Macro shot of very small Velella. Foreground is a penny. Photo by Lloyd MaxfieldEvery avid Oregon beachcomber is familiar with Velella velella, or by-the-wind sailors: little (typically 4 to 6 cm.) violet-blue floating creatures that are often stranded by the hundreds or thousands on the beach April through July. They live in vast congregations on the sea’s surface, in warm and temperate ocean water around the world. They have no means to propel themselves; rather, they move at the whim of wind and current. They’re driven ashore by strong west winds, the same winds that wash glass floats, plastic bottles and other debris from the “Great North Pacific Garbage Patch” onto our beaches.
The “sail” is Velella’s most distinctive feature; it’s what catches the wind, and it’s all that’s left—dry as parchment, or soft and rubbery—after the rest of the animal has rotted away. It’s also the source of Velella’s name (velum is Latin for sail). Hanging from the fringes of the float are tentacles that contain stinging cells; you might not feel the sting on your fingers, but take care to not touch your eyes next.
A few fun facts about Velella:
• The sail of Velella is set at an angle, like a sailboat tacking into the wind. Those commonly found on Oregon beaches are set from 11 o’clock to 5 o’clock (or northwest to southeast). Another form of Velella, more commonly found south of Mendocino, California, is a mirror image of our more northerly Velella; its sail is set from southwest to northeast.
• Among the creatures that prey on Velella are the ocean sunfish and the violet snail (a type of marine gastropod that also floats on the open ocean).
• Technically a single Velella is not one creature but many: a colony of plant-like animals, each with different tasks such as reproduction or digestion.
• Velella used to be considered a close relative of the Portuguese man o’ war. Both are members of the class known as hydrozoans, are deep blue in color, float on the open ocean, and have stinging tentacles that help them catch prey (microplankton for Velella, larval and small juvenile fish for the man o’ war). But the two are now classified in different orders.
Learn more about Velella velella by visiting the online Sandpiper, a publication of Range Bayer and Yaquina Birders & Naturalists.
—Bonnie Henderson, with Range Bayer and Cynthia Trowbridge
Contact: Phillip Johnson, CoastWatch Director, (503) 238-4450, or EMAIL