Barn Owls molt their feathers gradually throughout their lives. However, there is some variation in the timing. For example, while the female is incubating eggs and tending young chicks, she is permanently at the nest for almost 2 months, during which time she is fed by the male. During this 'down time' she molts some of her feathers, when there is less pressure on her to hunt efficiently. At the same time, males suspend their molt while provisioning the female and young, and rather than have energy spent on replacing feathers, it is used to provide food for the female and young over the entire breeding period. Once the breeding season is over, both male and female resume the gradual molt of their feathers.
The video below was filmed a few nights ago at one of the Duhallow nest sites in a derelict cottage. Very fresh pellets (indicating the adults are still present) and a series of newly molted feathers, including a large flight feather (a primary). There were fewer feathers about two weeks ago and during the last visit to the cottage was utterly silent – no young chicks calling for food and no activity noted around the nest – the conclusion being that it is most likely that those adults have failed to breed, and as a result, have resumed their molt.
