November - February
The young will have been on individual territories by the start of winter but the numbers of small mammals will decline as winter sets in, making it more difficult to locate prey. Bad weather can have a disastrous effect on their ability to hunt, it is the time of the highest natural mortality. The survivors will get to know their territory and may establish several roosts which may eventually become nest sites.
Many barn owls remain in their territory throughout the winter, paired with the same mate. If the weather is mild the pair may start courting as early as February but this not usual.