The northern fur seal (Callorhinus ursinus) population in the Pribilof Islands Archipelago (on St. Paul and St. George Islands, Figs. 1-3) makes up approximately 50% of the world population. Smaller breeding colonies are located on the Kuril and Commander Islands in Russia, Bogoslof Island (Fig. 4) in the southeastern Bering Sea, and San Miguel Island (Fig. 5) and the Farallon Islands off California. The rookeries at the Farallon, San Miguel and Bogoslof Islands were probably colonized in 1996 (Pyle et al. 2001), the late 1950s (DeLong 1982) and 1980 (Lloyd et al. 1981), respectively.
