These peregrines nest mostly on cliffs, river bluffs, trees, tall towers, and building ledges. They have no real nest, but will often use abandoned nests of eagles, hawks, and ravens. Breeding pairs stay together throughout the non-breeding season, and most stay together indefinitely. Roughly two young are fledged per breeding pair per season. This species of falcon hunts by diving at high speeds and hitting its prey in mid-air.
Adults have virtually no predators, and are therefore at the top of their food chain.
This position makes them vulnerable to bio-accumulation. This term is used to describe the process in which toxins are amplified towards the top of a food chain. Pesticides, and other harmful chemicals, accumulate in tissues of insect-eating animals. These poisonous chemicals are further concentrated by raptors that consume insect eaters. There are many ways that such chemicals affect American Peregrine Falcons, such as killing them directly or affecting behaviors, like nest defense.