I did a search and couldn't find any reference to anyone else speaking of robins belling. As in singing their good night and good morning songs, sounding like bells. I've always thought of it as "the robins are belling" ever since this one evening hike many years ago.
I was in the woods later than I meant to be, it was getting dusky and I still had a couple miles to go. I could still hear the owls (why I lingered so long in the first place), but as I hurried along I kept thinking I was hearing bells ringing in the distance. Finally I turned into the last section but one, a stretch of fairly open woods because of tornado damage a few years previously. And suddenly I could hear the source of the bells, it was a hundred robins (I have no idea of the number, really) singing their hearts out as they got ready to settle in for the night.
I was so astounded I just stood there with my mouth agape until it was almost completely dark. I have a flashlight in my pack of course, well I have a head-light now, but back then just a flashlight, but I didn't use it, I didn't want to lose the magic so quickly. I managed to stumble (or float) my way through the rest of the hike to my car. I know the trail by heart, anyway, even back then I already did.