gulls and ashy storm petrels, the latter species being considered endangered and a conservation priority. The island also is the wintering ground of several species of migrants, and regularly attracts vagrant birds (about 430 species of bird have been recorded on or around the island). Seals Five species of pinniped come to shore on the islands, and in some cases breed. These are the northern elephant seal, harbor seal, Steller's sea lion, California sea lion, and the northern fur seal (the last of which, like the rhinoceros auklet, began to return to the island again after protection). Sealers took 150,000 northern fur seals (Callorhinus ursinus) from the Farallons between 1810 and 1813, followed by Russian fur hunters who lived on the Farallons and extirpated the pinnipeds from the islands. In 1996 West End Island became the fourth American northern fur seal rookery when a pup was born. The recolonizers bore tags from San Miguel Island in the Channel Islands, which had been itself recolonized in 1968. By 2006, nearly 100 pups were born. The fur seals are aggressive and have displaced larger sea lions from their territory. The high count for 2011 was 476 individuals, a 69 percent increase from the year before. By 2016, the pup count alone was 1,126, reflecting a 21% average (but highly variable) annual increase in new pups over the 21 years since recolonization. If the South Farallon Islands population reaches its estimated historical size of 100,000 individuals, it could account for approximately one-fifth of the world's northern fur seal population. Northern elephant seals (Mirounga angustirostris) recolonized the refuge in 1959 with a confirmed pup in 1972. The elephant seal rookery on Southeast Farallon has probably reached carrying capacity. Whales Several species of cetaceans are found near the Farallon Islands, most frequently gray whales, blue whales, and humpback whales. Blue whales and humpback whales are most frequently found near the islands in the summer and fall, when strong upwelling may support a rich pelagic food web. Orca whales are also found around the islands. Gray whales are reliably found near the Farallones during their spring migration north and the fall and winter migration south. Some gray whales may also be found during the summer, when a few whales skip the trip north to Alaska and spend the summer months off the coast of Canada and the continental United States. In December 2005 one humpback was