are unique to the islands and found nowhere else in the world. Marine life ranges from microscopic plankton to the endangered blue whale, the largest animal on earth. Archeological and cultural resources span a period of more than 10,000 years. Headquarters and mainland visitor center The visitor center is located in the Ventura Harbor. The visitor center contains several exhibits that provide information regarding all five islands, native vegetation, marine life and cultural history. Also, visitors can enjoy a short film, free of charge, that provides an overview of all five islands. The visitor center is open every day, except Thanksgiving and Christmas, from 8:30AM–5:00PM. The average annual visitation to the mainland visitor center was around 311,000 in the period from 2009 to 2018, with 366,250 visiting in 2018. Recreation Channel Islands National Park recreational activities include backpacking, camping, day hiking, scuba diving, and spearfishing. Channel Islands National Park is renowned for its large number of complex, beautiful sea caves. Kayaking through the sea caves is popular. Based on ocean conditions and ferry availability, Scorpion Anchorage on Santa Cruz Island is the most visited area in the park for day and camping visitors. Camping visitors arrive at Prisoners Harbor on the north shore and stay in the valley beyond. A new island visitor center opened at Scorpion Ranch on Santa Cruz Island on April 6, 2009. Although most visitation occurs in the summer, migrating gray whales and spectacular wildflower displays attract visitors in the winter and spring. Autumn is an excellent time to travel to the park, as well as for diving, as the days are usually sunny, with minimal winds and clear ocean water. It is recommended that inexperienced visitors use caution when visiting the national park due to changing ocean conditions in this unique ecosystem. The National Park Service authorizes a small number of guide and outfitter services. Visitation to the islands and waters is low, with about 30,000 visitors traveling to the islands, and another 60,000 who only sail within park waters. Gallery Vessels The CINP unit operates several vessels in the waters of the park, including the following: Surf Ranger LCM-8 landing craft, 74 ft. research diving boat Pacific Ranger 56 ft. Sea Ranger II 58 ft. Ocean Ranger 100 ft. Sea Ranger 41 ft (retired). See also California coastal sage and chaparral ecoregion Channel Islands of California List of California Channel Islands wildlife List of