Eastside exterminators Birds are beautiful creatures, but they can cause messy property damage and costly headaches for property owners. Flocks of pigeons, sparrows, starlings, and seagulls can leave large deposits of bird droppings, which can stain and seriously damage paint, concrete, and other building surfaces. Bird nests built on roofs or under roof eaves can be unsightly, messy, and spread diseases such as encephalitis, histoplasmosis, Newcastle Disease, and salmonellosis to humans and pets.