How Santa Cruz Got Its Fox Back

California’s Channel Islands comprise an archipelago west of Santa Barbara, most of them now uninhabited by humans. Our historical tenure there, though, laid the foundation for one of the most challenging, intricate contemporary conservation stories I know of, the subject of T.C. Boyle’s most recent work, When the Killing’s Done.

Spanish explorers used Santa Cruz Island as a coastal base in the mid-19th century, and introduced feral pigs as an easy, self-sufficient food reserve. In the absence of predators, the pig population flourished, and when the sheep ranchers who had used the island for decades finally abandoned it in the 1970s, these porcine invaders essentially had the island to themselves.

At the same time, DDT dumped offshore by the Montrose Chemical Corporation was filtering up the marine food web, accumulating in the tissues of fish and marine mammals, and eventually reaching the regional population of piscivorous bald eagles, Haliaeetus leucocephalus. As the bald eagle population crashed in the 1980s, the apex predator niche was opened to a new and ecologically different species, one not native to the island ecosystem. The golden eagle, Aquila chrysaetos, a large raptor native to the mainland ecosystem, had historically visited the Channel Islands, but because of competition with territorial bald eagles, never colonized the area. Attracted to the feral piglets, an abundant and reliable source of prey, these aggressive predators moved in. However, it soon became apparent that golden eagles weren’t on a strict pork diet.

From the day an ancestor rafted across the blue waves some 20,000 years ago, the island fox, Urocyon littoralis spp., has been the primary terrestrial carnivore on the Channel Islands. A descendent of the mainland gray fox, Urocyon cinereoargenteus, this small canid—adults weigh between 2 and 6 lbs—is endemic to the islands; each is home to its own subspecies, six in total. Around the time the first golden eagle nest was found on Santa Cruz in the mid-1990s, the island fox population began to decline steeply, as much as 95 percent between 1995 and 2000. At its lowest point, the Santa Cruz island fox population was down to 62 individuals (from a historical estimate of roughly 1500). Observing golden eagles hunting, monitoring their nests, and keeping tabs on fox populations around the island allowed biologists to identify predation by golden eagles as the cause of death in nearly 90 percent of fox mortalities between 2000 and 2004.

The imminent threat of extinction to the Santa Cruz island fox provoked a hugely controversial response by the National Park Service and the Nature Conservancy, which owns a substantial portion of the island. Recovery plans involved an elaborate scheme of helicopter-netting and relocating golden eagles, a fox captive-breeding program, New Zealand-based sharpshooters who exterminated roughly 5,000 feral pigs, and a bald eagle reintroduction program. Close to ten years later, the various pieces of the puzzle have come together. The first bald eagle chick hatched on the island in 2006, the pigs are gone, and though vagrant golden eagles may still cast their shadows on the scrubby hillsides, the fox population is self-sustaining and quickly approaching pre-crash numbers.

In his latest novel, T.C. Boyle embarks on a fictionalized retelling of this struggle over the Channel Islands’ ecological fate. With his inimitable, vividly eccentric style, he pits NPS biologists against dreadlocked animal rights activists in a tale of gunslinging and exotic species in the New West, presenting diverse perspectives on the morality of meddling with nature. He’s well-versed in the islands’ cultural and natural histories, and endows this epic with meticulous details from the lives of its characters to create a complex, compelling portrait of the havoc we wreak, and the lengths we go to in search of redemption.

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