Year-round freshwater spring © Gary N. Crabbe

With no paved roads and only a handful of historic ranch buildings, the island’s wildlife population far surpasses its human population. More than 1,000 species of plants and animals inhabit Santa Cruz Island’s high peaks, vast meadows and dramatic coastline. Incredibly, 12 of these species are found nowhere else in the world; another 48 are found only on the Channel Islands.

So rich and unique are the island’s flora and fauna that for decades, scientists from around the world have traveled to Santa Cruz Island to study its unusual plants and animals. The island houses the University of California’s largest Natural Reserve System site—a field laboratory for biological, cultural and geological research.

Geography

Never connected to the mainland, Santa Cruz Island was once part of a larger land mass known as Santarosae, which, as sea levels rose, separated into four distinct islands—Santa Cruz, San Miguel, Santa Rosa and Anacapa—approximately 11,500 years ago.

At 96 square miles, Santa Cruz Island is the largest and most geographically diverse of the eight Channel Islands. Seventy-seven miles of coastline surround two parallel mountain ranges that cradle a pastoral central valley. Steep canyons slice through rugged peaks as high as 2,000 feet, and freshwater springs flow year-round.

Ocean-plunging cliffs rim much of the island, interrupted by the occasional rocky cove, or by long stretches of sandy beach along the western and southern shores. Santa Cruz Island harbors some of the biggest natural sea caves in North America. Painted Cave, one of the largest, is known for its colorful rock types, lichens and algae.It is nearly a quarter mile long and 100 feet high just inside the entrance.

Santa Cruz Island’s diverse terrain hosts an astonishing array of wildlife. More than 680 species of plants occur on Santa Cruz Island, including eight species found nowhere else on Earth. Santa Cruz Island also harbors numerous types of terrestrial—or land—animals, including four unique species.

Added to the federal endangered species list in March 2004, the Santa Cruz Island fox has been the island’s top predator for thousands of years. The diminutive fox, the harvest mouse and the Santa Cruz Island deer mouse are all endemic to Santa Cruz Island, meaning they exist nowhere else. A fourth mammal on Santa Cruz Island—the spotted skunk—is unique to the Channel Islands.

These animals share the island with various bats, snakes, salamanders, frogs, and 220 species of bird, including the Island scrub jay. Larger and deeper blue than its mainland cousin, the Island scrub jay, recognized as a new species in 1996, is found only on Santa Cruz Island.

Santa Cruz Island lies within the boundary of the Channel Islands National Marine Sanctuary, which extends six nautical miles offshore of the northern Channel Islands. The sanctuary’s waters teem with extraordinary life, nurtured by a fertile combination of warm and cool currents. Forests of giant kelp flourish offshore, providing important nurseries for fish and invertebrates. More than 26 different species of cetaceans, including the endangered blue, humpback and sei whales, pass through on seasonal migrations. Onshore, sea lions and harbor seals sunbathe on beaches, while marine birds—including California brown pelicans, California least terns and western gulls—hover and nest nearby.