Fifteen species of prey were utilized by nesting Prairie Falcons (Falco mexicanus) as determined through pellet analysis. Thirteen-lined Ground Squirrels (Spermophilus tridecemlineatus), the most common prey, were present in 91% of the pellets, followed by Western Meadowlarks (Sturnella neglecta) which were present in 56% of pellets. Horned Larks (Eremophila alpestris) and Lark Buntings (Calamospiza melanocorys) were found in 23% and 12% of the pellets, respectively. Additional prey species were present in low frequencies (≤55%). Eighty-nine percent of pellets contained both bird and mammal remains. Four percent of pellets contained only bird remains while 7% contained only mammalian remains.