Barn Owls and Jackdaws have a very uneasy relationship. Jackdaws are often found nesting at the same sites as Barn Owls – derelict buildings and ruins, especially old chimney systems – and they can compete directly for the same nest sites. On the one hand, Barn Owls nesting in chimneys will often only find the site suitable after Jackdaws have repeatedly dropped sticks down the shaft in the hope of blocking it and forming a protected nesting platform. Barn Owls will often take over these stick nests deep inside chimneys, and a third or more of all Barn Owl nests in Ireland are as a result of them commandeering old Jackdaw nests. On the other hand, several suitable Barn Owl nest sites, and sometimes Barn Owl nest boxes, have been filled with sticks by Jackdaws to the point where they are no longer of use to the owls
Where there is an established Barn Owl nest, as in this instance at a site in Co. Kerry, despite there being dozens of Jackdaws in the vicinity, all seem to know to avoid the old farm shed with the owls in it. Barn Owls can and will kill an intruding Jackdaw. This short clip, taken yesterday evening, shows an unusually brave, or an unusually foolish Jackdaw land on a beam in the shed, only to have the resident Barn Owl take a swipe. No doubt this intelligent and fast-learning crow will know not to chance his luck there again.
Lucky Jackdaw (Video: M.O'Clery).