6/10/2013: Finally discovered that all the 'chattering' up behind my barn is a pair of nesting Cooper's Hawks. I've seen one perched on a dead tree there, but never thought there could be a nest. Turkey Vultures were coming in close yesterday and the hawks have been chattering and chasing them away today. I stayed home from work today to try to observe and get better photos to identify the pair. Always looking for a reason to stay home from work :-) I've made this its own gallery with photos taken to try to positively identify it vs. a Sharp-shinned Hawk. The shape of the tail helps identify. Thanks Joe Neal for your assistance with identification!