Beginning Chapter 4 of Wake-Robin, by naturalist John Burroughs. A detailed look at the nesting habits of Red-headed Woodpeckers, Yellow-bellied Woodpeckers, Pine Siskins, Cedar Waxwings, Robins and Indigo Buntings. Burroughs marvels at the dirty jobs parent birds must endure to keep their nests clean for their young. Any parent who has changed a dirty diaper can relate.
The Creative Commons and public domain contains a wealth of images, music and more. The images used in these show notes link back to the contributors.