Many many years ago I was leading a canoe trip on the Susquehanna River. We'd come to a particularly strange stretch: bot banks of the river for about a hundred yards had dead, leafless trees on both banks. The river was about 100' wide at that point. Anyway, on one side of the river on the tree limbs were approximately eighty crows. On the other side on the tree limbs were a dozen owls. Man, that was eerie. Remined me of my youth when gangs would cluster and wait until something happened to start the fight. I have no idea to this days what was up. I got us outta there pdq. Someone on Mudcat about two (?) years back said that crows and owls do not get along. I can well believe that.