Many people have probably seen birds picking up small pieces of man-made materials, like strips of a plastic bag or paper litter, and taking them into their nest. This behavior appears to be fairly widespread among birds. What's unique about some larger bird species, like certain vultures, eagles, and falcons, is that the same nest is used for centuries if it continues to be in a safe space. Generations of birds will continue to occupy and add materials to these nests for hundreds of years.