Pigeons often roost on the edges of balconies and ledges giving them plenty of chances to mess up your car or property their “guano”. Pigeons have become a common sight here in Delta of the last several years. The Rock Dove has pale grey feathers with two black bars on each wing. Now that Fed-x and the internet have taken over the jobs for carrier pigeons they are considered a nuisance and a pest by many. Pigeons carry many diseases that can cause serious health problems including; salmonellosis, tuberculosis and toxoplasmosis. Pigeons do not have natural defense mechanisms to protect against predators yet they are not in any danger of vanishing. To help rid pigeons around your home: Eliminate bird feeders, seal areas where they can nest, place a fake owl on your roof and spray water to scare them off.
http://www.delta-optimist.com/opinion/blog-the-poor-pigeons-a-k-a-rock-doves-1.2177474