Kyla Woods
Contributing Writer
Thousands of thin, translucent blue creatures have washed up on UC Santa Barbara’s beach shores over the past few weeks. Though it may be challenging for Gauchos to identify what they are, they are not a type of plant or trash. Instead, these organisms are actually a sea animal known scientifically as Velella velella, or, more commonly, as by-the-wind sailors or marine hydrozoans.
Marine hydrozoans wash up on shore in droves because of wind currents and the animal’s physical build. The transparent, oval-shaped appendages on top of the hydrozoan’s blue body operate as a “sail” that is pushed by the wind. Upwelling, a wind phenomenon that brings nutrient-rich waters to the surface of the ocean, concentrates the animals together, and they are then pushed ashore by the wind. Since hydrozoans primarily live in the warm waters of the Pacific, they often wash up on the west coast of the United States.
Although hydrozoans share some similar physical features with and resemble jellyfish, they are only a distant relative. Hydrozoans and jellyfish are both cnidarians, a taxonomic class of invertebrates (animals that do not have backbones). Hydrozoans, however, are more accurately colonies of small, predatory organisms that inhabit saltwater bodies.
They are mostly present in ocean environments, however there are a few found in freshwater environments. Marine hydrozoans have the form of polyps and medusae. Polyps are stationary and consist of tube-like forms. They reproduce aesexually by budding which is basically when a bud develops on the creature and breaks off, eventually turning into another organism. This organism is the medusae which is a free-swimming organism which usually resembles a jellyfish. Medusae reproduce sexually by releasing sperm and eggs in the water, this is also known as spawning. Other well-known hydrozoans include the Portuguese man o’ war and the immortal jellyfish.
Storms and natural winds contribute to the seasonal droves of hydrozoans in southern California. Climate change adds to this pattern, since there have been reports of them washing up during the winter months due to uncharacteristically warm water.
Once hydrozoans are on the shore, they eventually die by drying up in the sun, or they are eaten by predators such as sea slugs or purple snails. When they die through dehydration, they lose all their color.
Even though marine hydrozoans die after being beached, it is advised not to touch them due to their stingers. These stingers are used to hunt plankton and are relatively harmless to humans besides causing slight irritation. When you see these creatures on the shore, dead or alive, it is best to avoid direct contact with them. If you do handle them, make sure to wash your hands thoroughly after, and avoid touching your eyes or other sensitive areas.
Like all animals, marine hydrozoans need a clean environment to survive. Students can help preserve their habitats by picking up trash and remaining considerate of the creatures around them while visiting beaches. Get involved with local activities that involve recycling, beach clean-up and other environmental projects. In order to preserve the beaches and animals that live here we need to work together to make our environment less polluted.