Two conservation groups have asked the federal government to impose new restrictions on oil and gas development in the West to protect the greater sage grouse, a popular game bird on the decline.Scientists contend sage grouse breeding areas are suffering.

While biologists and politicians fight over whether the greater sage grouse should be labeled an endangered species, 10 Western states allow hunters to take aim at the reclusive, ground-dwelling bird.Listing the sage grouse under the Endangered Species...