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A Tale of Two Species

When the world’s fastest bird, the Peregrine Falcon, was removed from the endangered species list last year, naturalists across North America celebrated. Decades of hard work had finally paid off. But while one species disappeared from the list, others waited to be added. The most recent candidate for such distinction is the Yellow-billed Cuckoo, which will soon be the subject of a comprehensive review by the U.S. Fish and Wildlife Service.

It's a dubious honor, to be sure. A species must be in danger of extinction throughout all or a significant portion of its range to qualify as endangered. Once that designation is made, though, the federal government becomes obligated to protect the species. Usually this means overseeing recovery efforts and helping to protect its habitat.

The Peregrine Falcon spent twenty years listed as an endangered species. Efforts to boost its numbers included captive breeding programs and the protection of nest sites during the breeding season. Another important factor was the banning of DDT, a pesticide that caused the birds to lay thin-shelled eggs that broke during incubation. At one point the number of breeding pairs of Peregrine Falcons in all North America dropped to a low of 324. Now it stands at more than 1,600.

The Yellow-billed Cuckoo, a slender, long-tailed bird, brown above and white below, faces a different set of obstacles. The Southwest Center for Biological Diversity, which petitioned the U.S Fish and Wildlife Service to have the bird protected in the West, blames cattle grazing, dam building, agribusiness, and urban sprawl for the bird's demise. The service's announcement on February 17 that it would study the Yellow-billed Cuckoo suggests that at least some of those claims might be true.