Each year businesses, government agencies and individuals spend thousands of dollars cleaning up after and repairing damage caused by pest birds. Nesting and roosting birds leave behind debris and droppings that can cause serious damage to buildings. Bird droppings are acidic and can quickly erode building materials. Along with the damage pest birds cause to buildings, their feces can carry any of 60 transmittable diseases. These diseases can be harmful to children and others with compromised.