
The eastern end of Anacapa Island is seen from offshore
During the last ice age, when the sea level was 300-400 feet lower, the four islands off our coast were connected and part of a larger, single island called Santarosae. 20,000 years ago, when the sea level was at its lowest point, Santarosae covered roughly 790 square miles and was just four to five miles from the mainland, which extended further out from today’s coastline.
It would’ve been a tempting sight off the coast, and I’ve often wondered what it would’ve been like to traverse this super island from end to end. However, lacking a time machine, it is still possible to hike on all four of the islands and imagine what it was like and how it’s changed over the millennia.
20,000 years ago, California was also wetter and cooler. Santarosae and southern California had a climate more akin to Northern California today. Redwood trees could be found along our coast, and Santarosae was more forested with conifers such as Bishop pine, Douglas fir, and Gowen cypress, that supported a diverse understory. As southern California became drier and warmer, oak woodland and chaparral became more dominant, with conifers on the mainland retreating to higher elevations where the environment was still relatively cooler and wetter.
As the sea level rose, Santarosae’s coastal plains and lowlands became inundated, separating the higher portions of the island. Between 11,000 and 9,000 years ago, Santarosae was gradually broken into the four smaller islands we know today – Anacapa, Santa Cruz, Santa Rosa, and San Miguel. These four islands combined cover roughly 195 square miles, about a fourth of their original size, with Anacapa Island, the smallest, covering just over one square mile.
The oldest record of humans on the Channel Islands dates back 13,000 years ago, with the discovery of Arlington Springs Man on what is now Santa Rosa Island, and so the first Chumash people did visit and likely live on Santarosae when it was a single island.
Today, Anacapa Island remains the closest island to the mainland, just 11 miles from the shore. The easiest way to reach the island is through Island Packers, www.islandpackers.com, which offers boats rides to all four of the islands, as well as Santa Barbara Island, which together comprise Channel Islands National Park.
While the boat ride is not the same as paddling out to the islands, watching Anacapa Island come into view is still striking. Off the eastern end of the island is the Arch Rock. The iconic arch and nearby spires are composed of weathered volcanic material, as is most of Anacapa Island.
The islands were formed underwater, roughly 15-20 million years ago, and literally rose up from the sea about five million years ago. The block of land that comprises the Transverse Ranges was originally oriented north-south and located where San Diego is now. Through the movement of tectonic plates, as the Pacific Plate moved northward against the North American Plate, this block of land was dragged north and rotated 90-100 degrees over the past 20 million years, arriving where it is now, and assuming the east-west orientation it has today.
As this block of land was dragged and rotated, it caused the sea floor to thin; the reduced pressure allowed molten magma to form and rise from the earth’s mantle, erupting as undersea lava. As the lava met the cold waters of the Pacific Ocean it cooled rapidly creating many of the features that can still be seen today. In some places this volcanic material is as much as 10,000 feet thick.
Five million years ago, when the Pacific Plate captured what is now Baja California and drove it into Southern California, the resulting compressional forces uplifted the islands, as well as the other mountains in our area.
As the sea level continued to rise, breaking up Santarosae, Anacapa Island was further weathered and eroded into three separate islands connected by a thin strip of land that’s visible during low tide, forming what is now Eastern, Middle, and Western Anacapa Islands.
Today, just Eastern Anacapa Island is open to visitors. From the landing harbor, a set of stairs leads up to the top of the island.
From April to June, visitors are immediately greeted by Western gulls, which are busy nesting on the ground all over the island. Free from mainland predators, the gulls and their chicks can dominate the island with their activity. Anacapa Island is one of the largest breeding areas for Western gulls.
A trail from the top of the stairs leads towards the Visitor Center, which is located amongst several other buildings associated with the lighthouse and National Parks Service. Restrooms can be found near the Visitor Center, as well as at the campground towards the middle of the island.
From the Visitor Center, a figure-eight loop hike can be made that provides a tour of the island, a total of about two miles. A short trail also leads out towards the lighthouse adding less than a half-mile roundtrip. All of the trails can be hiked during the time allotted on a typical day visit though Island Packers.
I opt for the trail that traces the northern side of the island. Years of sheep grazing on Anacapa Island from the late 1800s until the 1930s, have reduced most of the larger chaparral plants to a few isolated patches, mostly at the western end of the island. However, there is still a reasonable amount of plant cover with a mix of non-native iceplant and native plants such as island tarweed, goldenbrush, and island morning glory.
Other birds on the island include rufous-crowned sparrow, orange-crowned warbler, and Allen’s hummingbird. There’s also one species of land mammals, the Anacapa Island deer mouse, as well as side-blotched and alligator lizards.
The trail quickly arrives at Cathedral Cove. From the overlook, there are often harbor seals and California sea lions that can be seen sunning themselves on the rocky beach below.
From here, the trail turns inland, arriving at the campground, and joining the northern half of the loop. The campground has seven sites, each with a picnic table and food storage box. There is no shade and visitors must bring their own water. Reservations are made through Recreation.gov.
Continuing west from the campground, the trail quickly branches. I take the southern route this time, which climbs up a rise and leads past a Chumash midden. Although, there were no permanent Chumash settlements on Anacapa Island due to the lack of available water, it was an important stopover between the mainland and the other islands. The island also provided places to gather shellfish, hunt sea mammals, and fish offshore, similar to the other islands.
The Chumash call the island Anyapakh, which means ever-changing, perhaps a reference to the island’s appearance from a distance which can sometimes alternate between a single island and three separate islands.
Past the midden site, the trail continues through a large stand of giant coreopsis. Coreopsis are part of the sunflower family and can also be found along the coast on the mainland. The plant blooms from March to April with lush green foliage and bright yellow flowers, the plant appears more or less lifeless when dormant.
The trail then arrives at Inspiration Point, which offers sweeping views westward across Middle and Western Anacapa Islands, and beyond them, the eastern end of Santa Cruz Island and its Montañon Ridge.
Taking in the view, I watch as two hawks fly over and land on Middle Anacapa Island, making it appear tantalizingly close. Both Eastern and Middle Anacapa Islands are essentially flat plateaus rising above the sea. However, Western Anacapa Island retains more of its mountain ridge character and includes the highest point of the three islands, Summit Peak, at 936 feet above sea level. Chaparral and small oak woodlands can still be found in two of the island’s larger and deeper north-facing canyons.
Western Anacapa Island also represents one of the largest California brown pelican rookeries or colonies along the coast. California brown pelican was listed as endangered in 1970, due to reproductive failure from DDT pollution entering its food chain, which caused the birds to produce eggshells too thin to support the embryos in reaching maturity. DDT was banned in 1972, since then the pelicans have rebounded dramatically.
On the return loop, along the north shore, the trail passes Pinniped Point, which can also provide views of harbor seals and California sea lions on the rocky beach below.
From the Visitor’s Center a short hike can be made towards the lighthouse.
The first light on the island was a tower with an acetylene beacon built in 1912. The structure was replaced in 1932 with the current lighthouse, which was later automated in 1966.
In 1938, Anacapa and Santa Barbara Islands became a National Monument. They were later combined with San Miguel, Santa Rosa, and the eastern portion of Santa Cruz Islands in 1980, to create Channel Islands National Park.
An interpretive brochure for the island, along with information about visiting and exploring Channel Islands National Park, can be found online at www.nps.gov/chis
This article originally appeared in section A of the October 22nd, 2018 edition of Santa Barbara News-Press
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