The California Least Tern (Sterna albifrons browni) breeds from San Francisco Bay south along the coast of California to the Mexican border. It has also been reported earlier in the century breeding in Baja California, Mexico, at Scammons Lagoon (Bancroft 1927) and at the tip of the peninsula at San Jose del Cabo (Lamb 1927). There have, however, been no published reports of Mexican colonies in recent years.