Southern California's Channel Islands are home to cat-sized foxes (Urocyon littoralis) found nowhere else in the world. After DDT killed off the islands' native bald eagles in the 1950s, golden eagles moved in, preying primarily on feral piglets but snatching up tiny foxes, too. Disease further shrunk fox populations. When the foxes were listed as federally endangered in 2004, two islands' wild populations had already vanished, since biologists had collected the most vulnerable subspecies for captive breeding ("When endangered foxes are on the menu," HCN, 8/04/08).
Since 1999, land managers have rid the islands of feral pigs, relocated golden eagles, and reintroduced bald eagles and foxes. Although still listed as endangered, this ecological rebalancing has been a boon to foxes. The Nature Conservancy calls it "one of the fastest and most effective endangered species recovery programs in U.S. history." Bald eagles are nesting here again, and Santa Cruz Island, which hosted only 55 foxes in 2004, now accommodates some 1,300.