Sparrows, starlings and pigeons are the most troublesome of the birds commonly found in the urban environment. When these birds congregate in large numbers their droppings can create a foul-smelling, unsightly mess.
Netting can effectively be used to exclude birds from virtually any kind of structure and from roosting or nesting in trees. The net will not entangle birds. Netting may be draped across the front of buildings; fasten it tightly from above windows to below the ledge to discourage perching.
Most birds prefer to perch on flat surfaces. Surfaces with an angle of 60 degrees or greater cause birds to slide off when they try to land. Wood or metal sheathing cut at an angle can also be added to the problem area. Another deterrent is to install porcupine wire on ledges and rails where birds roost. Thinning tree branches will remove perch sites and reduce a source of wind protection, which may force the birds to move to another site. Combinations of noise (AM/FM radio, wind chimes, firecrackers, banging pots and pans) and visual stimuli (colored flags, reflective tape, revolving lights, balloons, replicas of hawks and owls) used persistently can evict birds. Control measures should be initiated as soon as the problem is identified.