I have 2 border collies.....Roxie wants the birds in the pen! Angus just lays in front of the gate and counts them as they go in and out! They keep all other dogs out of the yard....Angus is almost 3. We were afraid we would have to get rid of him. He got a baby chick. Shook it like a toy and when it quit making noise he dropped it and it was of course dead. I found it a little bit later, but did not realize it was Angus. He did not tear them up or pull them apart and make them bleed...He did not seem to pay any attention to the other chicks. MY BIG mistake! Another dead baby chick the next day. They 3rd time I caught him shaking the baby chick and took it away from him. I was really upset, but he has never taken another chicken. There were 4 more babies and I watched him like a hawk....he loves those chickens. Most of my flock is over 5 years old except those. And they are 2 now. We have foxes in the neighborhood and a family of hawks (red tail) That had a nest in the tree above the hen pen. I swear that mom comes by in the spring to the living room window to let me know she is back. I have not had trouble with hawks.