Well in one of my other posts I had a problem with coyotes but this was before I got my chickens. I've tried to bang on anything with a shovel to make horendous noises, tried throwing big stones at them, attempting to hollar loud and deep at them to make myself appear more menacing. All to no avail. My son took our male dog around the perimeter and let him mark the entire boundry line to our property. So far it has seemed to work. Not to mention I do have my 22 ready to go if need be.
Our fencing for our chickens is buried in the ground and toe'd out with quik cement poured over top of it. Also have netting covering the top of the run. I've placed a fake horned owl on a post to serve as a duel purpose for the chickens as well as my garden. Of course they have their coop that they get put into at night and we have holed up anything that resembled a hole...even down to the quarter inch. I don't want snakes or rodents if I can help it. We also built our coop 2 feet off the ground.
I am also getting ready to buy at least one of the Night Hawks and our friend said that he can get us a huge street light to put on the side of our house and place it on a timer. Other than continued observation from you, I believe everyone has basically covered all the bases. Best of luck to you. Let us know how it goes.