Seattle, WA, USA
After the young fledged I cleaned out the bird house where the Bewick’s Wrens built their nest and was surprised that so much plastic wrap was used to build the nest with. Notice also the long dark hairs. I would guess they are from racoon? There are few if any sticks, mostly moss, feathers (blue jay, flicker, etc) and bamboo leaf. I pulled most of the plastic out and set it beside the nest for the picture.
At any rate another discouraging case of the pervasiveness of plastic throughout the environment.