Damage and Disease
Birds are typically viewed affectionately by the general public but bird droppings can cause disease and are responsible for millions of dollars of property damage each year. The uric acid in bird feces is highly corrosive and can cause extensive damage, including eating through paint, roofing materials, and even some metal surfaces. Some experts say bird droppings may have contributed to the collapse of the interstate bridge over the Mississippi River that occurred in Minneapolis, Minnesota, on August 1, 2007.
Bird droppings can expose humans to many dangerous diseases; over forty known viruses and sixty transmittable diseases are directly associated with birds and their droppings, including salmonella, histoplasmosis, meningitis, encephalitis, and West Nile virus. It is estimated that histoplasmosis alone infects over 90% of all pigeons in an average flock.