Castle Rock National Wildlife Refuge

Castle Rock National Wildlife Refuge was established in 1979.  Located about half a mile offshore from Crescent City, California, and rising 335 feet above sea level, 14 acre Castle Rock is unique among the more than 1,000 offshore rocks and islands in the state in that it has so many types of habitat on one large island within an extremely productive region of the Pacific Ocean. Habitat features include relatively deep topsoil, vegetated terraces, sheer rock cliffs, talus slopes, a tiny beach of pebbles, and reef habitat. The cliffs provide nesting habitat for one of the largest breeding populations (100,000) of common murre on the Pacific coast. Ten other species of seabirds also nest here, including three species of cormorants, pigeon guillemots, Cassin’s and rhinoceros auklets, Leach’s and fork-tailed storm-petrels, and tufted puffins. Because many of these bird species nest in burrows and crevices and are primarily nocturnal, they avoid predation by western gulls that also nest on the island.

Castle Rock also serves as an important haul out (resting site) for marine mammals, including harbor seals, northern elephant seals (both bear pups there), and California and Steller sea lions.