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The first bald eagle born on Santa Cruz Island in more than a half century is retrieved from its nest and carefully lowered to the ground.
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Ecological Triage Brings an Island Back From the Brink of Collapse
by Jane Braxton Little
High on a ridge on Santa Cruz Island, field biologist Dave Rempel plants his right foot on a flat rock and leans out over the cliff as far as he dares. Straining to keep his balance, he searches the treetops until a slight movement catches his gaze.
“There,” he exclaims in a sharp whisper. Two hundred yards away, in a broad nest of sticks and dried grasses, a bald eagle chick stretches its scrawny wings in the May morning sun. Six weeks old and barely half its full 14-pound potential, this bird is the culmination of a 25-year restoration program.
It is the first bald eagle born on Santa Cruz—or on any of the Channel Islands—in more than half a century.
“This is a miraculous event,” says biologist Lotus Vermeer, Santa Cruz Island project director for The Nature Conservancy. “It proves that given a chance, nature can heal itself."
Still tufted in soft gray down, the chick is the result of a complex multi-phased effort to undo the ecological cycle of events unleashed by past settlers on Santa Cruz Island, the largest of the chain of eight Channel Islands rising out of the Pacific Ocean off the Southern California coast due west of Los Angeles.
Centuries of human activity here have wreaked havoc. Some native species are gone forever. In their place are non-natives that have invaded the island and may never leave it.
This year, however, signs of recovery are everywhere. The eagle chick hopping about the nest near Rempel’s precarious lookout is the first of two born on Santa Cruz this year. In pens scattered throughout the dense cover of the island’s coastal sagebrush and oak woodlands, the birth of 21 Santa Cruz Island fox pups has bolstered the fox population, threatened with extinction just two years ago.
And thanks to a dramatic reduction in non-native feral pigs, which dig up soils and destroy plants, spring has brought a profusion of wildflowers, including brodea and mariposa lily. Coreopsis are flaunting their golden blooms on canyon walls, and the rare Santa Cruz Island silver lotus is creeping back from cliff edges where it had retreated from the feral animals. All are sure signals of progress in the effort to re-establish the island’s delicate ecological balance.
The Galapagos of North America
 Santa Cruz Island, California |
Never connected to the mainland, Santa Cruz evolved in isolation over millions of years, slowly developing distinct species. These endemic plants and animals include a scrub jay bigger and bluer than its mainland counterpart and the diminutive Santa Cruz Island fox, one-half the size of its ancestor, the mainland gray fox.
This ecosystem started to unravel in the mid-1800s, when European settlers introduced domestic livestock that eventually left tens of thousands of sheep and pigs running wild to breed on the island’s rugged slopes and in its pastoral valleys. With no predators, they reduced the native vegetation to stubble, causing widespread erosion that led to massive landslides. The Santa Cruz Island monkeyflower has not been documented since 1932, and the island’s lacepod, barberry and bush mallow remain threatened with extinction.
The entire island was in danger of ecological collapse in 1978, when the Conservancy acquired an interest in it. (In 1987 the Conservancy received the majority of the island through a bequest.) Rampant pigs and sheep were only part of the problem. Santa Cruz Island had also lost the bald eagle, one of its key species. The cause was an unrelated human legacy: the pesticide DDT. In the absence of the territorial bald eagles, golden eagles from the mainland began colonizing Santa Cruz, sustained by the year-round supply of feral pigs. Once there, they also began preying on the native fox population, nearly driving the animal to extinction.
