Rare purple sea creature spotted on SoCal beach. Could warming waters be the cause?

A Rare Discovery on the Beach

Oceanographer Anya Štajner was taking a sunset walk along La Jolla Shores beach when she noticed a vibrant violet color in the sand. Curious, she got down on her hands and knees and was stunned to find a rare species of sea snail known as Janthina. These creatures, commonly called violet snails, are known for their striking purple shells and the delicate bubble raft they create to stay afloat in the open ocean. They are not typically found on Southern California beaches.

When Štajner saw the snail, she immediately recognized it but was completely shocked. As a fifth-year PhD student at the Scripps Institute of Oceanography at UC San Diego, she said she never expected to see one washed up in San Diego. The chances of such an occurrence are extremely low.

Janthina snails are pelagic, meaning they live at the surface of the ocean rather than in tide pools or along the shore. Their bright violet color is believed to offer protection from the sun's harsh rays. This discovery marks the first time that Scripps researchers have spotted these violet snails on local beaches in a decade.

Typically, Janthina snails are found in warm subtropical or tropical seas. Their occasional appearances along the Southern California coast often happen when warmer offshore waters flow toward the shore. On the day Štajner found the snails, the water was notably warm. She recalled the moment the snail washed up on her feet, saying, "Whoa, this is hot."

While Štajner cannot confirm whether this discovery is linked to climate change, she mentioned that it is a question researchers will want to explore in the future. She emphasized the importance of monitoring if these warm waters continue, as it could lead to more sightings of violet snails on the shore.

If beachgoers spot Janthina in Southern California, Štajner encourages them to take photos and send them to Scripps. However, she reminded the public that certain beaches, like La Jolla Shores, are designated "no take areas" where removing living creatures is prohibited.

In total, Štajner collected around ten snails and brought them to the university's Pelagic Invertebrate Collection for further examination. Under the microscope, she observed thousands of eggs in red sacks inside one of the shells. She also studied the delicate purple whorls on the snails' shells.

Štajner explained that Janthina snails usually have a darker violet hue on the top of their shell to blend in from above, while their underside is lighter lavender to help them avoid predators from below. The snails shimmer along with the sun on the ocean's surface, making them harder to spot.

These sea snails are also fierce predators, feeding on free-floating hydrozoans such as Velella velella and Portuguese man o' war. Despite their small size, they are powerful creatures. Štajner expressed excitement about the public attention her discovery has received and hopes it inspires more people to explore the diverse aquatic life along Southern California's shores.