The nest of a Baltimore Oriole fell from its tree in Sunday's wind. I found it on the ground on some land I routinely bird. This is a nest from last year; orioles have yet to return to Minnesota this spring. It had hung from a branch in a large willow tree. I did some reading on these nests. They are built almost exclusively by the female bird. It takes her from one to two weeks to complete the job. Flexible plant, animal, and sometimes human-made fibers form the outer shell, put in place first. Fibers tie the nest to anchor branches. Springy fibers are next woven into that framework to shape the sac-like nest. Downy fibers line the pocket. The material is gathered one piece at a time. Orioles are known to fly as far at a quarter mile one way to find appropriate building material. The photos show you the intricate and complex construction better than I could describe it. There must be hundreds of fibers in the nest. Consider how far the bird flew during contruction as it gathered nesting material. If she averaged no more than 50 yards per flight, one way, one fiber would be 100 yards, 52 fibers would be a mile, 520 fibers would be 50 miles. A nest like this is not only a work of art, but also simply work. A new nest is built each year.