I have been feeding a group of crows for twelve years. I live in Northern Arizona, about 7 miles NE of Flagstaff, AZ. The crows appear to be healthy and I've never seen them fighting with each other. I've not noticed any injuries. In general they cooperate with each other. If I'm late with the food, there are usually one or two crows who have been assigned to let the others know when I put the food out. They don't usually eat any food before the rest of the crows arrive. But they start calling loudly when I put the food out. Sometimes one will fly off and get the others if they don't come soon after being called. A few years ago a family of Ravens showed up. There are 5 of them but initially a pair came and then a couple years later, there were five that were sometimes here together. The crows give way to the Ravens who eat some food for a while and then leave long before all the food has been eaten. I've seen squabbles at the food dish occasionally among the crows, but nothing that looked serious, and I've not seen the ravens do that, nor have I seen any squabbles between the crows and ravens. I wonder how the crows that are left to notify the others know they have been assigned to this duty. In the fall I notice the crows look ugly - they are probably molting - but it is the feathers around their heads that look the worst. Their necks start to look scraggly. In winter we get the biggest groups - sometimes up to 40 crows. In spring the number of crows drops off drastically, and in summer they bring fledglings to our house. I'm enjoying this course.