This thesis reports the density, reproductive chronology, nesting success, and diet of Swainson's Hawk (Buteo swainsoni) in the Chihuahuan Desert grasslands of south-central New Mexico during 1974 and 1975. The average density for both years was one pair per 9.45 km2. The mean laying date for 1974 was May 5 and was May 6 in 1975. The mean hatching date for both years was June 11. Clutch sizes ranged from two to four eggs with the average clutch size for the combined years being 2.8 eggs. The combined mean number of fledglings per nest was 1.6. This fledging rate is similar to other studies. A total of 522 prey items were identified in these samples; items represented 21 different species, which is the greatest variety of prey reported for Swainson's Hawk.