Thousands of bizarre blue creatures were spotted on the beaches of South California. Initially, many were confused about what they were as they were not jellyfish or Portuguese Man O' War.

Bizarre Sea Creatures in California Beaches Are Cousins of Portuguese Man O' War

Point Reyes National Seashore, a unit of the National Park Service, shared a photo of the shore covered with blue sea creatures on Facebook. According to them, they are called velella velella (V. velella).

Velella velella are cousins of Portuguese Man O' War (P. physalis). They are not single organisms but colonies of thousands of polyps, each with its function for feeding, protection, and reproduction.

Rita F. T. Pires, a Portuguese Institute for Sea and Atmosphere research assistant, agreed that the blue creatures are Velella velella, also known as By-the-Wind Sailors. She told Newsweek that usually forms large agglomerations when beached, as what's the case in California.

She noted that Portuguese Man O' War is a siphonophore. Both species belong to the Cnidaria phylum. However, Velella velella is more similar to a jellyfish than the Portuguese Man O' War.

They float on the ocean surface their whole lives and are usually 2 to 3 inches long with a rigid sail on their backs, allowing them to move in the wind, which could lead them to be blown toward the shore. Their tentacles are also short compared to the Portuguese Man O' War.

In addition, Velella velella also goes through a medusa stage in its life cycle. According to Manoa, medusa bodies are shaped like an umbrella with the mouth and tentacles hanging in the water. They are motile, and they swim freely in the ocean. Jellyfish are medusae (singular form medusa).

Lisa-ann Gershwin, a former research scientist at CSIRO and a science writer specializing in jellyfish, told Newsweek that they are the other part of the jellyfish's lifecycle. However, they have another part similar to a tiny coral polyp or sea anemone stuck to the bottom. According to her, when the medusa stage has babies, they become polyps. When the polyps have babies, they grow up to be medusae.

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Velella Velella Washed Up En Masse

Velella can be washed up in large numbers, as they did in Southern California due to strong winds and rapid reproduction.

According to Pires, the species' large strandings on beaches in the spring coincide with times of enhanced reproductive activity. They are regular and natural occurrences (blooms) that fit with the species' life cycle.

A hydrozoan called V. velella is observed drifting and using a sail-like structure to float at the ocean's surface. Thus, like the [Man O' War], their onshore transit is governed by specific wind and current conditions.

According to Point Reyes National Seashore, their little blue tentacles don't sting humans. They are designed to gather zooplankton or fish eggs for consumption.

However, Pires advised against touching them because each person may react differently, and it can still cause minor allergic reactions. The expert said that the stinging cells will still respond mechanically to touch even if stranded on the beach.

Gershwin agreed, adding that they have stinging cells and fragile mucous membranes. So, one should avoid touching their tongue or eyes after handling them. However, she said it's best not to handle them at all.

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