They attract a greater number of birds to use the property. Their faeces contain a number of harmful pathogens, leading to diseases such as Salmonella, Psittacosis and E.Coli. The feathers and nesting materials contain numerous insect pests i.e. flies, fleas and mites. Corrosion and staining of the building structure. Bird faeces falling directly onto pavements outside of your premises could be hazardous to pedestrians and could result in a serious accident.