Cooper's Hawk in the yard

This morning I heard an unusual ruckus coming from the chicken pen in the back part of our yard. I rushed out to see what was going on, and saw a large hawk swooping over the yard, coming from the chicken run area. It settled on a low dead branch of a nearby tamarack tree, to watch as I approached. Usually as soon as I open our front door, the hens come running to the edge of their pen to wait for snacks and attention. Now, not a single hen was visible, obviously hiding from the hawk. They were all hiding under a huge pile of dried sticks and branches which we have left in their yard as shade/cover, and now I was extremely glad they had this refuge. I neared the tamarack and the hawk flew off, but not before I could get a fairly good idea of colouring to identify it.

I am pretty sure it's a Cooper's Hawk, and once I read more about this type of hawk I was pretty assured that's what we had. The Cooper's Hawk is well known by farmers and has earned the nickname "chicken hawk" for it's predatory nature on chickens in poultry yards. It's main diet is smaller birds, as well as chipmunks and other small mammals. In the 1950s-60s the Cooper's Hawk population dwindled, and some suspect it was due to DDT chemical spraying. Today, populations have risen again to the point where these hawks are becoming nuisances again. They are becoming well-known in urban areas as well (as cities encroach on farmland and hawk habitat), and many urban chicken keepers mention seeing these hawks in their yards or even having their hens attacked (and sometimes eaten). We back onto the railroad tracks lined by tall trees, and have heavy tree cover at the back fence of our property, so plenty of places for this hawk to live. I know this may all be part of nature, and the life of a farm (urban or rural), but I would be very upset to see one of our hens taken. We'll have to consider covering the run with mesh to keep unwanted predators away as this hawk may become a regular visitor now that it knows the hens are here.