This picture was taken at 5am with a camera phone so sorry about the quality, as you can see they are clustered up around the entrance, I would guess the temp at about 58 degrees. The bottom is open (6"X36") and they have drawn out 12 of 20 top bars. They dont cluster like this during the day or at least not that I have seen. I would guess the cluster is about 1 1/2 inches deep, and about 5" high by 5" wide. Just curious if this is normal ?