Anacapa Island is a small volcanic island located about 11 miles (18 km) off the coast of Port Hueneme, California, in Ventura County. The Island is composed of a series of narrow islets 6 mi (10 km) long, running in a mostly east-west orientation, 5 mi (8 km) east of Santa Cruz Island. The island is composed of three islets: East, Middle and West Anacapa, collectively known as the “Anacapas” by some authors. The islets have precipitous cliffs, dropping off steeply into the sea. East and Middle Anacapa have fairly level areas at their tops, but West Anacapa is wider and reaches an altitude of 930 ft (283 m). Middle Island reaches an altitude of 325 ft (99 m) and East Island is 250 ft (76 m) at its highest point. All three islands total 699 acres (283 ha), or about 1.1 square miles (2.8 km2).
Anacapa is part of the Channel Islands archipelago (island chain), and is part of the Channel Islands National Park. It is the smallest of the northern islands. The islands are defined by the United States Census Bureau as Block Group 8, Census Tract 36.04 of Ventura County, California. The official 2000 census population was 3 permanent residents (Ranger Station in the eastern part of East Island), and the total land area was 2.947 km2 (1.138 sq mi). The highest peak is Summit Peak 2 on West Island, 930 ft (283 m).
East Island's most notable natural feature is Arch Rock, a 40-foot (12 m)-high natural bridge.
Anacapa Island, located only about 11 mi (18 km) from the urbanized coast of Southern California, provides critical habitat for seabirds, pinnipeds such as California sea lions, and several endemic plants and animals. Great white sharks, feeding on pinnipeds, are found in the waters of the Channel Islands, including Anacapa. The island has a somewhat diverse flora, including around 150 native plants, including 16 endemics (two of which are unique to the island) plus many introduced species. Removal of sheep about 1938 and rabbits in the 1950s has allowed the vegetation to begin to recover.
Anacapa has around 69 species of birds. The island’s steep lava rock cliffs incorporate numerous caves and crevices that are particularly important for the increasingly rare seabird species, Xantus’s Murrelet (Threatened) and Ashy Storm-petrel. The largest breeding colony of the California Brown Pelican in the United States, and one of the only two in California, also occurs on Anacapa Island. This is where the Brown Pelican has been able to recover so dramatically from near extinction in the 1970s. The islets of Anacapa also host the largest breeding colony of Western Gulls in the world. Western Gulls begin their nesting efforts at the end of April, sometimes making their shallow nests just inches from trails. Fluffy chicks hatch in May–June and fly away from the nests in July. There are four mammals on the island, including a unique subspecies of deer mouse (Peromyscus maniculatus anacapae) which occurs only on this island. The island has two reptiles, including an endemic form of the interesting and attractive Side-Blotched Lizard (Uta stansburiana). There is one amphibian, the channel islands slender salamander (Batrachoseps pacificus). Marine mammals and other marine life abound on Anacapa.
Anacapa’s prolific and dense vegetation was once dominated by the showy Giant Coreopsis (Leptosyne gigantea) previously names Coreopsis gigantea, an erect, shrubby perennial with a stout, succulent trunk growing to some 8 ft (2 m) tall. The main trunk grows up to 5 in (13 cm) thick and often resembles a small tree. During its blooming season, March to May, it bursts forth with a mass of showy, bright yellow flowers and green leaves. Giant Coreopsis provided shelter and perches for seabirds and land birds, and nesting habitat for many. The prolific seeds provided abundant food for the endemic Anacapa deer mouse, and for many small birds. The island’s stands of Giant Coreopsis, as well as all the other plants of its coastal bluff community, were devastated by sheep grazing in the late 1800s and early 1900s, rabbit browsing in 1910-1950s, and by large-scale destruction of native vegetation associated with facility and road development by the U.S. Coast Guard during construction and manning of the Anacapa Light Station. Only small patches and individuals of native plants remained.
After completion of the lighthouse and associated facilities, the Coast Guard planted two types of iceplant on East Anacapa Islet: red-flowered iceplant (Malephora crocea) and sea fig, aka ‘freeway iceplant’ (Carpobrotus edulis x aequilaterus). Both are highly invasive. The National Park Service has initiated a restoration project to eradicate all of the ice plant by 2016, the centennial of the National Park Service Organic Act.
Invasive ship rats (Rattus rattus) are thought to have been introduced to the island from the wreckage of the SS Winfield Scott. They had devastating consequences for the island's seabirds and other native species, but were successfully eradicated in 2001–2002. With the rats gone, the number of rare Xantus' Murrelets has increased more than 80 percent in the last three years. This is one of many recoveries following invasive species eradications from the Channel Islands.
In The Channel Islands of California (1910), Charles Frederick Holder says of Anacapa
Arid appearing, desolate, wind-swept, Anacapa is withal a valuable possession to its owner, and one of the picturesque islands of the entire group. Its strange rocks, moving, passing, intermingling, made a strong impression on my mind, an impression of warring nature, conflicts of wind and rock, of seas eating into its very vitals, of caves that undermine it, and of the old rock fighting for its very life against the sea.
On the night of December 2, 1853, the sidewheel steamer Winfield Scott running at full speed crashed into the rocks off Middle Anacapa and sank. All of the passengers survived and were rescued after a week.
The United States Coast Guard built a light beacon in 1912 and a light station in 1932 (Anacapa Island Light). It was the last lighthouse built by the United States Lighthouse Service. The lighthouse is located on the eastern part of the island, at the entrance to the Santa Barbara Channel.
On January 31, 2000, Alaska Airlines Flight 261 crashed near the island.
- Lois W. Roberts, Anacapa Island (McNally & Loftin, West, 1983) ISBN 0-87461-040-0, ISBN 978-0-87461-040-6
- David Edward Bunnell, Sea Caves of Anacapa Island (1993)
- Susan Lamb, George H. H. Huey, Channel Islands National Park (Western National Parks Association, 1998) ISBN 1-877856-74-6, ISBN 978-1-877856-74-7
This region experiences warm (but not hot) and dry summers, with no average monthly temperatures above 71.6 °F. According to the Köppen Climate Classification system, Anacapa Island has a warm-summer Mediterranean climate, abbreviated "Csb" on climate maps.
- Block Group 8, Census Tract 36.04, Ventura County United States Census Bureau
- Owen, Ken. Anacapa Island Blog (http://anacaparestoration.blogspot.com/). July 2011
- Island Conservation - Where We Work
- Charles Frederick Holder, The Channel islands of California: a book for the angler, sportsman, and tourist (1910), p. 189
- Gudde, Erwin; William Bright (2004). California Place Names (Fourth ed. ed.). University of California Press. p. 12. ISBN 0-520-24217-3.
- McCall, Lynne; Perry, Rosalind (2002). California’s Chumash Indians : a project of the Santa Barbara Museum of Natural History Education Center (Revised ed.). San Luis Obispo, Calif: EZ Nature Books. ISBN 0936784156. Retrieved 2013-04-26.
- "Winfield Scott - Vessel History". Channel Islands National Marine Sanctuary. 2010-07-15. Retrieved 2013-04-26.
- Climate Summary for Anacapa Island, California
|Wikimedia Commons has media related to Anacapa Island.|
- Channel Islands National Park
- Channel Islands National Marine Sanctuary
- Anacapa Island Site with Photos and History
- Winfield Scott History
- Anacapa Island Restoration Blog
- Volunteer on Anacapa Island!