Nesting is nasty!
Whether commercial or residential, pigeons sure know how to make a mess. One mating pair quickly turns into a small family. Within a year or two your house or commercial building can literally be covered with fecal matter. Pigeons are attracted to the scent of their mothers droppings. When left alone, pigeons and their offspring will stay together on your structure until the end of their natural lives.
Pigeons are abundant in cities and around rural areas. They conflict with humans for several reasons. Their droppings deface buildings, kill vegetation, and are aesthetically displeasing when deposited on benches, sidewalks, and cars. Around grain elevators, pigeons consume and contaminate grain destined for human consumption.
Birds are known vectors of disease. Pigeons do not carry West Nile Virus, which recently has been blamed for thousands of sick people and a few deaths. One way birds get people sick is when mosquitoes, ticks, or mites, feed on the birds and then on us. In this way disease is spread to humans. West Nile Virus is not the only disease to worry about. Pigeons carry Pigeon Ornithosis (psittacosis), Encephalitis, Newcastle disease, Toxoplasmosis, Salmonella food poisoning and other diseases. Histoplasmosis, a fungal disease that can infect people, can be contracted when cleaning up accumulations of dusty pigeon manure. Pigeon ectoparasites such as mites, fleas, ticks, and bugs may readily bite people.
Pigeons are also considered a hazard around airports. Pigeons have been known to cause roof leaks, from huge accumulations of droppings, which in time will either rot away a roof, or dam up rainwater that may sit on the roof for weeks, until it finds a way into the structure.