“Are they shrimp?”
“Are they lobsters?”
“Why are they taking over!?”
“Can we eat them?”
To put your inquisitive minds at ease, I present to you the Pelagic Red Crab (Pleuroncodes planipes) also sometimes referred to as a tuna crab or langostilla for our Spanish-speaking friends. Not a shrimp, kind of a lobster (this is a ‘squat’ lobsters and finds itself in a different family Galatheidae than the lobsters you were thinking from the family Nephropidae). Adult red crabs are approximately 32-34 mm (carapace length) and range in color from pale orange to bright red. Juveniles and adults are generally distributed through the water column (pelagic/planktonic) until they reach a carapace length of about 17-20 mm, in which they can mostly be found on the bottom of the ocean (benthic). They are quite abundant near the west coast of central and southern Baja California. Pelagic red crabs breed from December through April, with the peak reproductive season occurring in February.
Mass stranding events, such as the ones we have seen, are an annual occurrence in places such as Bahia Magdalena, and apparently recur on the same beaches and during the same season of year. These Baja strandings are primarily due to winds, waves, and currents. However, California strandings are more often associated with El Niño events, which enable the populations to move northward in warm water currents originating in the south.
As to their edibility… To quote a decently reliable source, “They are also delicious, once sold as “finger lobster” at the Sizzler during the mighty 1983-84 El Nino.” Do with that as you will, but remember no collecting in the park.
If you happen upon in any strandings in the San Diego area, feel free to drop a line to my inbox with the 411. When, where, and approximately how many (hundreds or thousands?). Inbox: email@example.com
Also, if you have any more questions, I am always more than happy to chat about squishy ocean critters.
Alexandria M. WarnekeScientific Outreach CoordinatorCabrillo National Monument Conservancy