natural enemies?

This morning a fox got into the yard and attacked the hens. It wasn't even that early—just around breakfast time. I heard the commotion and ran outside; before I even yelled the fox saw me and took off, dropping the hen he was trying to carry away (Springdot the Speckled Sussex). My first instinct was to call for the dogs, who were upstairs with Leah settling in for a morning of office work. They didn't respond instantly, which is probably just as well: unlike Rascal in his prime, Scout and Blue aren't trained to chase away foxes and ignore chickens. The hens were already panicking, and adding two excitable puppies to the scene would probably have made things worse rather than better. Oh well, we're working on it. And they did get come out a little later, once all the hens were safely locked up, to check out the scene of the crime and get their first scent of fox. Next time, they'll be ready!