Historically, San Clemente Island (SCI) had some of the highest catch landings of white abalone in southern California. However, after 1975 the population suffered a sharp decline throughout its entire range. Intense commercial and recreational over-fishing is attributed as the main cause for the decline. Following the dramatic decrease in population, white abalone were federally listed as endangered under the Endangered Species Act in 2001. Currently, very few white abalone can be found in the deep rocky reef habitats offshore from the banks of SCI, along with green and pink abalone making SCI an important area for monitoring and recovery for many species of abalone.
Coming from the same class as snails and slugs, the white abalone has an oval-shaped shell and attaches to the rocky ocean bottom with their strong, muscular foot. The bottom of their foot is orange with blotchy orange-tan sensory extension which has tentacles. On average, white abalone are generally 5-8 inches long, but can grow up to 10 inches and weigh approximately 1.7 pounds.
White abalone have a complex life cycle which attributes to their slow population recovery. They reproduce by broadcasting their eggs and sperm into water column, once fertilized, the eggs hatch after only one day into larvae. Eventually, those larvae will change into the adult form settling out from the plankton to a hard surface where it will attach. Because white abalone are broadcast spawners, they need to be within three feet of a member of the opposite sex in order to have successful fertilization. Since the decline, white abalone are frequently found alone, and thus have little chance for successful fertilization because the males and females are too far apart to be able to reproduce.
Although commercial and recreational abalone fishing laws have been put into place that do not allow taking white abalone, there are still extremely low numbers of isolated survivors. National Marine Fisheries Service recovery and conservation efforts are underway with a captive breeding program and a four-step restoration plan. Navy-funded surveys for white abalone around SCI have provided population information in waters that have historically supported large numbers of this species. Navy natural resource managers are committed to continue to aid in the recovery of white abalone.