I have welded wire on my run, but my chickens are locked up securely in their coop at night when most predators here are out. I have hardware cloth buried about a foot deep under ground and then up the sides about 3 ft. I also have a motion sensor light by the run, but that doesn't stop anything. This run worked well for the first couple of years, but this winter, when my lab, who used to like to sleep outside, died, a coyote got into our backyard (over a 5ft fence) and then jumped the 6ft run fence and broke into my old coop which had welded wire on the openings. The coyote got 4 of my 6 chickens. I now have added 3 feet of wire to total about 9 ft high around the whole run. I also have an electric fence that runs around the whole run at almost the top of the run and at the bottom and then wire over the top. So far, I have not had any other issues, but if you have a lot of wild life around like I do, then I would say the more protection the better. I thought my girls were safe and was devastated when the coyote got in. It actually came back a few days later and got into the run again, but my remaining two girls were in the garage for the night, so it couldn't get them. My new coop is like fort knox, with an automatic door, and no uncovered openings that anything can get into. I felt horrible for my girls and what they went through and I am not going to loose anymore due to lack of protection for them.