If you get too close to a nest or a young fledgling, the parent juncos will often give a repeated, angry chip call. I don’t understand how this could possibly be adaptive—I would understand a snake-like hiss, or a tiger roar, but no one’s scared of “chip”—but as silly as it is for the parents to broadcast, effectively, “My nest is here, don’t come find it!” I do appreciate the help.
On our last trip we noticed SNAE and his unbanded mate chipping insistently.