The Red-shouldered Hawk breeds through southern Canada to the eastern edge of the Great Plains south to Florida, the Gulf Coast, and eastern Mexico in the eastern U.S.; only northern most populations are migratory (Dykstra et al. 2008) In the western U.S., this species is a year-round resident west of the Sierra Nevada Mountains from northern California to northern Baja California (Dykstra et al. 2008). In Montana, this species is an accidental spring and fall migrant (Montana Bird Distribution Committee 2012).
For a comprehensive review of the conservation status, habitat use, and ecology of this and other Montana bird species, please see Marks et al. 2016, Birds of Montana.