I found this enlightening….bluebirds will hold their own and protect their territory. The bluebird nest was started, so they were first. Upon returning, it was discovered this chickadee appeared “interested” in this box. See what happens. Who says bluebirds are ALWAYS kind and gentle creatures? Well, OK, usually they are. Enjoy seeing what competitors do to keep prime real estate–our manmade nesting boxes, of course! Humorous and educational material here. Good job on the video making, I say.