It’s a wistful moment when your backyard birds — like these Black-capped Chickadees — depart their nestboxes. By October, it’s time for one last duty as nestbox landlord: to clean it out. Cleaning will reduce the incidence of parasites in the box and make it more inviting to next spring’s tenants. It will also help you know for sure if it gets used again. Learn more at BirdNote.org.