Crow experts think big communal roosts provide warmth, protection from predators, shared knowledge about food sources, and a chance to find a mate. Follow crows to their roost some autumn evening, if you can, and watch these avian acrobats wheel in for the night.More info and transcript at BirdNote.org. Want more BirdNote? Subscribe to our weekly newsletter. Sign up for BirdNote+ to get ad-free listening and other perks. BirdNote is a nonprofit. Your tax-deductible gift makes these shows possible.