SAN DIEGO — Small sea creatures are swarming the waters near San Diego County beaches. And they've been here before.
The creatures are called tuna crabs or red crabs.
What are they?
The species is Pleuroncodes planipes or called tuna crabs, also commonly known as red crabs. They are omnivores and are usually fed on by blue whales, large fish, squid and birds.
Where are they from?
According to the Scripps Institution of Oceanography, tuna crabs are usually found in waters near Baja California. During warm weather or El Niño, tuna crabs can be found in large numbers near Southern California or Central California.
When they're seen in Southern California, they are usually found in large swarms of tuna crabs and can be found washed up on local beaches, according to Scripps Institution of Oceanography.
Charlotte Seid, Senior Museum Scientist and Collection Manager at the Benthic Invertebrate Collection at Scripps Institution of Oceanography told CBS 8 that although tuna crabs have been consistently found near the California coast since the 1950s, it's rare to see the creatures at scuba-diving depths so close to the shore.
Underwater photos shared with CBS 8 that were captured by Seid show dozens of the red crustaceans gathered on the seafloor.
Can you eat them?
Scripps Institution of Oceanography said do not capture, cook and eat these creatures.
Tuna crabs look similar to various crustaceous but according to Scripps, the tuna crabs have unknown toxins that may harm humans, so consumption is not recommended.
Have you seen them?
Scientists said it's important for researchers and citizens to document events like these in real-time.
Beachgoers and scuba divers are encouraged to contribute their sightings to programs like iNaturalist or the Environmental Education Foundation. Scientists said the photos help provide long-term context to the rare sealife events that happen so frequently in San Diego.
Photos: Tuna crabs swarm San Diego
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