Bird Proof Gel is a long lasting, non-toxic, tacky bird repellent for use on ledges, sills, beams, rafters and hundreds of other indoor and outdoor locations where nuisance birds alight or roost. Bird Proof repellent can effectively discourage pigeons, starlings, house sparrows and certain other nuisance birds from roosting on or returning to a treated area for up to one year. If birds see the material on a potential landing surface, they are not likely land upon it. If they do decide to land on a surface that has Bird Proof Gel applied, they find the sticky and slimy surface to be very uncomfortable and will not stay for long. They learn over time and do not return to the locations that have been treated with Bird Proof Gel.