Thousands of Red Crabs Stranded on Southern California Beaches

Posted on June 17, 2015

Thousands of red tuna crabs have been washing up on beaches in Southern California. The crabs are red pelagic crabs (Pleuroncodes planipes). A lone red tuna crab is pictured above in a photograph taken near the Scripps Pier in La Jolla.

The red crabs live their entire life cycle from larve to adulthood in the water column from surface to seafloor. They can't survive for long outside of the water. A Washington Post story says the stranding of the red crabs may be due to a radical change in a Pacific ocean weather pattern, which is driving the crabs northward. When the crabs get close to shore they are unable to swim back out to sea.

Linsey Sala, collection manager for the Pelagic Invertebrates Collection at Scripps Institution of Oceanography, UC San Diego, says in a statement, "Typically such strandings of these species in large numbers are due to warm water intrusion."

An OC Register article says the crabs have not been seen in the area for decades. This video of stranded crabs was filmed by Linsey Sala on a San Diego County beach. The crabs were also seen stranded in Newport Beach - as in the photograph above - and other beaches along the coast of Southern California.

Scripps advises against eating the red crabs "due to unknown toxins that may be present within the crabs."

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