Accipiter in the Yard

I was working at my computer this afternoon when a branch in a madrona tree seemed to shake rather violently.  I looked carefully and saw an accipiter hiding among the leaves.  I watched it for a minute to see if it would fly immediately but it didn't, so I rushed downstairs for the camera.  To save time, which is often of the essence with accipiters, I opted to try to sneak out the front door instead of return to my office door and deck. 

Before I could bring the camera to bear the accipiter flew to our bare pine tree and I managed to take a dozen or more photos while it was there.  It then flew to a higher branch and I obtained another dozen or so photos.  At this point I thought it was in danger of flying but it didn't, so I returned to the house. 

A few minutes later my wife told me it was out around our brush pile in the front yard.  I now had my camera upstairs (downloading from the memory card) so I went out on the deck and soon the accipiter emerged from the brush pile.  I think it knew there were birds in the pile and soon one flew, but the prey had a head start on the accipiter and it wasn't going to catch it. 

A little while later it was back in the brush pile, again hunting for birds.  By now the light was fading but I took another couple of photos.  It was really working the brush pile looking for prey.  The brush pile is not natural... I wired together livestock panels (1/4" welded rods composing 4" squares) in a box to protect the birds from predators, but the predators I had in mind at the time all had four paws!  However I know the small size of the squares made it difficult for the accipiter to maneuver in and out of the brush pile, hence the head start for the small bird I mentioned earlier. 

Since I'm not comfortable with the identification between a Cooper's hawk (which I suspect this probably is due to pervious sightings in the yard) and a Sharp-shinned hawk, I'll try to get a reading from a more experienced friend.