ABSTRACT
Three geographically distinct subspecies of the California sea lion, Zalophus californianus have been identified: Z. c. californianus along the west coast of North America, Z. c. wollebaeki on the Galapagos Islands, and Z. c. japonicus from the Sea of Japan. The California sea lion is commonly used as a performing and/or display animal in zoos and oceanaria around the world. The source of these animals has been (and continues to be) the North American population, in particular the islands off the coast of southern California. The Zalophus breeding season on the California Channel Islands begins in the latter part of May. Censuses utilizing aircraft are probably the most cost-effective way of covering the entire range of Zalophus. Small, high-winged, single-engine planes are the best observation platforms, although helicopters have been used.
