Nest sites and breeding habits
Peregrines are territorial, with each territory containing one or more nest sites. The territories are well-spaced, and their size is determined by the abundance of food.
The nest site
The nest site, known as an eyrie, is usually on a grassy or earthen cliff-ledge, quarry or other inaccessible undisturbed location. Buildings and other constructions are increasingly being used. Old nests of other species such as ravens are used elsewhere in the world, but rarely in the UK.
The nest itself is a slight scrape in earth or old debris on the nest ledge. No material is brought in to build a nest. The female forms the scrape using her chest and legs.
The female normally lays a clutch of three or four eggs in late March or April at 2-3 day intervals. Both birds share the incubation, which begins with the last or penultimate egg, and takes 29-32 days per egg.
The chicks hatch over a period of a couple of days, and have smaller size differences than chicks of most raptor species. Most of the brooding and feeding of small young is carried out by the female, while the male hunts to supply the food. After the first couple of weeks, the female shares the hunting.
The young fledge at 35-42 days, and are independent two or more months later. During this time, the adult peregrines teach the young to hunt and handle prey in flight. Less than a third of peregrines reach breeding age. Those that do can expect to live 5-6 years. The oldest known peregrine was more than 16 years old.