The Orange County Register reports that the crustaceans, which look like tiny lobsters or crawfish, created a bright red rim along the shoreline of Dana Point, San Clemente, Newport Beach and Huntington Beach on Sunday.
Experts say the 1- to 3-inch long crabs, which normally live off Mexico's Baja Peninsula, are going farther north because of the warm water that has lingered off Southern California for the past year.
In recent weeks, blue, jellyfish-like creatures known as "by-the-wind sailors" have been spotted, and tropical fish such as yellowtail and Bluefin tuna are showing up earlier than normal this year.
From Sandra Endo:
Thousands of small red crabs blanketed some Orange County beaches this weekend surprising beachgoers in Dana point.
Area resident Lauren Hickey says, "I thought it was seaweed like the red tide when I saw it over the weekend but then I see they are crabs."
Her mother Rhonda Hickey wonders if the crabs will be okay, "I've never seen anything like this and we've lived here three years."
Marine experts believe the warm weather pushed them north up the coast from Baja California. They haven't washed ashore here since the last big El Niño in 1997.
Dana point resident Tony Janicki says ,"it's unusual I wonder what's causing them to come here and be washed ashore in such large numbers."
By Monday morning area residents say there were far less crabs than over the weekend since the water swept a lot of them to sea.
OC life guards are telling beach goers to leave the crabs alone, they are only 1-3 inches big and not good for eating.
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