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Unusual-Looking Blue Creatures Reappearing in Large Numbers on California Beaches

Published on 11/04/2025 at 12:53
Também conhecidas como “velejadoras do vento”, as Velella velella flutuantes estão cobrindo as praias da Califórnia mais uma vez. Robin Wilson via Wikimedia Commons sob licença CC BY-SA 4.0
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Visitors to California Beaches Are Encountering an Unusual Scene: Thousands of Small Blue Creatures, with an Exotic Appearance, Are Emerging in Large Numbers on the Sand

Thousands of bright blue marine creatures have recently appeared on the beaches of California, leaving beachgoers surprised.

The animals, resembling jellyfish, have been seen in abundance along the coast, forming a blotch that impressed those who passed by.

Del Dickson, who was walking his dogs at Bolinas Beach in Marin County, described the scene as something “truly incredible.”

He told the San Francisco Chronicle that from a distance, the group of animals looked like “a patch of oil” spreading across the sand. Their mass presence marks, for many, the beginning of spring.

Meet the “Sailors of the Wind”

The creatures are known as Velella velella, also called “sailors of the wind.” They pose no danger to humans and usually appear on California beaches during spring or early summer.

According to the National Park Service, Velella have a blue or purple body, measure between 7.5 and 10 centimeters, and feed on plankton with the help of stinging tentacles. Although they are relatives of jellyfish, sea anemones, and corals, their behavior is different: they don’t swim, they only float, driven by the wind.

Each Velella has a sail-shaped structure that projects upward and allows the wind to carry it. This “sail” can have an orientation to the left or right. In the Northern Hemisphere, most tend to be left-handed, while in the South, right-handed ones predominate.

Why Do They Appear at This Time?

The explanation for the emergence of these creatures in large numbers lies in the phenomenon of upwelling. According to Raphael Kudela, a marine scientist at the University of California, this process occurs in spring when winds bring cold, nutrient-rich waters to the surface. This attracts phytoplankton and zooplankton, food for Velella, which end up concentrating in larger groups.

These groups, pushed by the winds, are eventually carried to the beach. Lacking control over their direction, they become stranded on the sand. When this happens, their bodies lose their blue color and become similar to brittle pieces of clear plastic.

Contact with Humans Should Be Avoided

Although they are not dangerous, Velella have small stingers that can cause skin irritation. Therefore, experts recommend not touching the animals, even when they appear inactive on the sand.

Carolyn Belak, an ecologist with HT Harvey & Associates, warned about the risk in 2023. According to her, although the threat is low, direct contact should be avoided as a precaution.

Although their arrival is not a rare event, researchers have been observing possible relations between the warming of ocean waters and the frequency of strandings of these creatures. In an interview with KQED last year, marine biologist Julia Parrish commented that these events could be a sign of ongoing changes.

“When we see signs coming from the ocean to the shore, we should pay attention,” she stated. The presence of Velella velella could be considered, according to her, an early warning of larger environmental changes.

A Reminder of the Unknown

Despite causing shock, these creatures also evoke fascination. For Jennifer Stock, an expert from the Greater Farallones National Marine Sanctuaries and Cordell Bank, they represent more than a passing natural phenomenon. “Velella velella offer a window of admiration and wonder for the vast ocean,” she stated. “And they show how much we know — and how much we still don’t know — about the planet’s largest habitat.”

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Fabio Lucas Carvalho

Journalist specializing in a wide variety of topics, such as cars, technology, politics, naval industry, geopolitics, renewable energy, and economics. Active since 2015, with prominent publications on major news portals. My background in Information Technology Management from Faculdade de Petrolina (Facape) adds a unique technical perspective to my analyses and reports. With over 10,000 articles published in renowned outlets, I always aim to provide detailed information and relevant insights for the reader.

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