Since swift watching is the current fad, perhaps there's a satisfying answer to a behavioral observation about swift roosting. Several years ago at the TOS meeting in Chattanooga, some of us watched the swifts going down a chimney near the restaurant. However, they didn't go straight in. Instead, they circled for several minutes, occasionally dropping down to the chimney but not going in right away. Why? It seemed to me that there might be a conflict-perhaps going in too early had a cost (getting hemmed in by others?) while getting in too late had a cost (too dark to see [but it's darker inside the chimney]) or not getting good contact with the wall, etc.). I've seen some videos of swifts inside a chimney, but that didn't seem to explain it. I wonder what the best spot in the chimney is and why. Thanks! Ed LeGrand Cumberland Co., TN