Wrens building their nest inside a hollow tree

A pair of Bewick’s Wrens made their nest inside this hollow tree (the video narration refers to them as Carolina Wrens but now we’re pretty sure they’re Bewick’s). The video shows both the outside and the inside of their nesting site and follows them as they build the nest.  The whole process took about a week, and you can see the nest grow from a few large twigs to a careful construction of small twigs, leaves, moss, fibers, and feathers.