Barn owls tend to use traditional nesting sites to breed.
Choosing a place to breed
Barn owls usually choose to nest in holes in trees, or undisturbed buildings such as barns and outbuildings, ruins and, in some areas, mines, cliffs and quarries.
Nestboxes are used in suitable circumstances.
Clutch size and breeding success depends on the availability of main prey species, so there may be considerable year-to-year variation in breeding performance. Laying 4 to 7 eggs is normal, but it can be between 3 and 11. These eggs are laid at intervals of two to three days. Incubation lasts 30-31 days but the female begins with the first egg.
Thus, young hatch at two to three-day intervals and are at different stages: the youngest may die if food is short. The young birds fly at 50-55 days.
Two broods may be reared. About 75 per cent of young die in the first year: survivors normally live for another one to three years. The greatest known age in Europe is more than 21 years; there are several records of 12-17 years.