In Utah's Uinta Basin, 21 species of raptors resided on or visited Oil Shale Tracts Ua-Ub from 1975 to 1985. As food resources change, especially certain rodent species and desert cottontails (Sylvilagus audubonii), synchronous changes occur in golden eagles (Aquila chrysaetos), northern harriers (Circus cyaneus), red-tailed hawks (Buteo jamaicensis), American kestrels (Falco sparverius), and loggerhead shrikes (Lanius ludovicianus). Suitable nest sites appear to be in excess, and there are no obvious effects of weather on populations. Fluctuations in territory size and density indicate competition has a minimal effect on populations. We conclude that opportunistic response to food resources is responsible for changes in the abundance of raptors.