Expert: Roger Lederer - 1/18/2008

Question
Dear Roger,
We have Four holiday lodges set around fishing lakes. Unfortunately the rooks that are nesting on our neighbours land are attacking the windows of the lodges - not only disturbing the customers at unearthly hours! but also making a mess on the glass and window frames.  Is there any deterrent that you know of?
many thanks Lesley Slade

Answer
Some birds are territorial and when they establish territories in the spring they become aggressive and chase off intruders. Unfortunately, they don't distinguish between their own reflection in a window (or car mirror) and try to chase that off. The solution to the problem is to eliminate the reflection. Misting the outside of the window with a very weak detergent or soda solution will eliminate the reflection but will also impair visibility for you. Awnings, eave extensions, and window screens will eliminate all reflection and stop the collision problem. Hanging ornaments such as wind chimes, wind socks, and potted plants also help. The behavior will stop when nesting ends.