Some falcons do migrate and some do not. There are some falcons in the midwest that do not migrate because the winters are not too severe and the food source or prey base remains adequate. Peregrine actually means wanderer in Latin. In remote areas, great horned owls, martens and some snakes prey on young falcons still in the nest. However, in urban areas peregrines have few predators.
Peregrines generally do keep the same mate from year to year.
However, if a member of the pair dies, the surviving falcon will accept a replacement mate sometimes as soon as a week after its mate died. Ohio's population of peregrine falcons is counted in terms of nesting pairs. Each spring, a pair of peregrine falcons usually nests in every major metropolitan area of Ohio including Toledo, Akron, Columbus, Dayton, and Cincinnati. Cleveland hosts several nesting pairs. In addition, there are also some sites where only a single falcon has been observed, likely attempting to set up a nesting territory.