SAN CLEMENTE ISLAND — The unique wildlife of San Clemente Island has survived the appetites and hooves of feral livestock, bombardments by Navy vessels and wave after wave of amphibious assault vehicles storming local beaches and grassy plateaus.
The operative word is "survived." Through it all, native species clung to life on the 57-square-mile volcanic isle about 75 miles northwest of San Diego that includes the only ship-to-shore bombardment training range in the United States.
The population of San Clemente loggerhead shrikes, a bird species, plunged to seven nesting pairs by 1990. A single San Clemente bush mallow, a species that once festooned the island with lavender flowers, clung to existence at the bottom of a steep canyon. Catalina grass was presumed extinct.
Now, however, thanks to a series of steps by the Navy, native plants and animals are showing signs of remarkable recovery.
With an annual budget of $3 million, a Navy captive-breeding program has boosted the number of shrikes here to 70 pairs. Across the island, signposts urge people to watch for the estimated 1,100 San Clemente Island foxes that call the island home, up from a few hundred a decade ago.
The Navy recently petitioned to have the San Clemente night lizard taken off the list of federally endangered species. An estimated 21.3 million night lizards occupy the 21-mile-long island, one of the highest densities of any lizard on earth. Dramatically bigger than its mainland cousins — up to 8 inches long compared with 2-inchers in the California desert — the lizard with bright stripes and mottled green scales spends its entire life within a few yards and bears its young live, as mammals do.
The Navy took the first big step toward restoring wildlife in 1992, when it removed feral goats and pigs — descendants of animals brought to the island by seamen as far back as 200 years ago. Equally important have been aggressive, hands-on restoration efforts including the replanting of native plants nurtured in greenhouses.
The military now takes wildlife into consideration even in areas reserved for military exercises. Sniper training has been reconfigured to avoid nesting areas; and bombing targets, including plywood replicas of enemy tanks and missiles, have been moved away from known populations of endangered species.
During a recent weekday tour of the island, owned by the Navy since 1934, Melissa Booker, the Navy's wildlife biologist for the area, said scientists "are seeing plants and animals slowly creeping out of caves and canyon bottoms and spreading out across the savannas. Some places that resembled cratered moonscapes are now covered with native shrubs so thick, it's hard to wade through them."
As she spoke, a submarine surfaced offshore near a Navy destroyer and several smaller vessels topped with rotating radar dishes. A few yards away, federally threatened sage sparrows flitted between clumps of federally endangered San Clemente Island Indian paintbrush.
Bombardment ranges remain on the southern end of the island. Beaches on the north will still be used for amphibious assault training. A heavily traveled road runs down the spine of the island.
Navy biologists may never know what San Clemente Island once looked like. But Navy botanist Bryan Munson said the return of native plant life "is changing the behavior of animals for the better."
For example, the expanding range of sage sparrows follows surges in vegetation that had been browsed into near oblivion by goats.
But the return of native vegetation could eventually pose a fire threat to San Clemente Island and Wilson Cove, its demographic center with a permanent population of several hundred military personnel.
"Eventually," Munson said, "we'll need more fire breaks, roads, controlled burns and other changes."
In the meantime, archaeologists have discovered 4,000 remnants of ancient Native American sites on the island.
Against vistas trimmed with cobalt blue that have changed little since Gabrielino tribe members roamed the island, archaeologists recently discovered a small boat hand-carved 500 to 1,000 years ago out of a chunk of igneous rock.
"The person who crafted this was an artist," Navy archaeologist Andrew Yatsko said, cradling the 11-inch-long object in his hands. "Whatever the intent was for creating it, it must have been done in very good times for this artist because these things take a lot of time and attention to make."
louis.sahagun@latimes.com
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