Massive numbers of bright red tuna crabs have washed up on San Diego beaches over the past several weeks. Pleuroncodes planipes (also known as tuna crab or pelagic red crab), have been seen in droves along the San Diego coastline, from Ocean Beach to La Jolla.
“Typically such strandings of these species in large numbers are due to warm water intrusions,” said Linsey Sala, collection manager for the Pelagic Invertebrates Collection at Scripps Institution of Oceanography, UC San Diego. Because of the long sampling history of the CalCOFI (California Cooperative Oceanic Fisheries Investigations) program, unusual events such as these can be compared and evaluated in context with other events in the program’s 66-year history.”
Tuna crabs primarily inhabit the west coast of Baja California, Gulf of California, and the California Current. The species is unique in that it can live its entire life cycle in the water column (surface to seafloor), from larvae to adulthood. Larger adult tuna crabs are known to inhabit the epibenthos (just above the seafloor), and make vertical excursions to the surface to feed on phytoplankton. Because they live in the water column, they are subject to the winds, tides, and currents.
Due to unknown toxins that may be present within the crabs, human consumption is not recommended.
• For more natural history information on tuna crabs, see the Zooplankton of San Diego Region website entry for this species: https://scripps.ucsd.edu/zooplanktonguide/species/pleuroncodes-planipes
Scripps Institution of Oceanography at the University of California San Diego, is one of the oldest, largest, and most important centers for global science research and education in the world. Now in its second century of discovery, the scientific scope of the institution has grown to include biological, physical, chemical, geological, geophysical, and atmospheric studies of the earth as a system. Hundreds of research programs covering a wide range of scientific areas are under way today on every continent and in every ocean. The institution has a staff of more than 1,400 and annual expenditures of approximately $195 million from federal, state, and private sources. Scripps operates oceanographic research vessels recognized worldwide for their outstanding capabilities. Equipped with innovative instruments for ocean exploration, these ships constitute mobile laboratories and observatories that serve students and researchers from institutions throughout the world. Birch Aquarium at Scripps serves as the interpretive center of the institution and showcases Scripps research and a diverse array of marine life through exhibits and programming for more than 430,000 visitors each year. Learn more at scripps.ucsd.edu and follow us at Facebook, Twitter, and Instagram.
About UC San Diego
At the University of California San Diego, we constantly push boundaries and challenge expectations. Established in 1960, UC San Diego has been shaped by exceptional scholars who aren’t afraid to take risks and redefine conventional wisdom. Today, as one of the top 15 research universities in the world, we are driving innovation and change to advance society, propel economic growth, and make our world a better place. Learn more at www.ucsd.edu.