Global Range: (<100-250 square km (less than about 40-100 square miles)) Most commonly encountered on Guadalupe Island and vicinity, off the Pacific coast of Mexico. Sometimes appears along California coast (e.g., see Hanni et al. 1997). Breeds on eastern coast Guadalupe Island; an incipient breeding colony occurs on Isla Benito del Este off central Baja California (Maravilla-Chavez and Lowry 1999). Each year 2-6 adult males and juveniles are seen on San Nicolas Island and San Miguel Island, California (California Department of Fish and Game 1990). A female and pup recently were seen on San Miguel Island, California (Melin and DeLong 1999). Adult males and nonbreeders also have been observed at the Farallon Islands, California (Matthews and Moseley 1990), though this was not mentioned by Reeves et al. (1992). Historical range may have extended from the Revillagigedo Islands (Mexico) northward to coastal waters of west-central California (Belcher and Lee 2002). Aurioles-Gamboa et al. (1999) discussed the southernmost records of this species, which extend to Guerrero, Mexico.