Birds in Houston, TX, annoy residents when they nest in and around homes. Local woodpeckers make some of the loudest sounds of any bird, scratching and pecking at the sides of houses to communicate or forage for insects. They also excavate holes in walls and attics for raising their young. More than simply traveling in noisy flocks and leaving behind repulsive droppings, birds can be dangerous to humans. Nesting parents are aggressive, and species like barn swallows or mockingbirds may attack people who intrude upon brooding sites. Bird infestations can also bring biting, parasitic mites into homes on their feathers.