How high is your apron? It looks like maybe three feet? We are putting in a new run and also have opossums and raccoons as our main predators.There is no need for one, if you are confident in your set up! I would suggest having a game camera or two, so you know whats lurking around at night.
Do you have some pictures of your coop and run that you can post?
I have a door on my set up, I've only used it a couple times. Every opening on my coop is covered with 1/2 inch hardware cloth. My run is all 1/2 inch HWC, it has a solid roof and I have an apron around the whole perimeter. I have 2 game cameras set up. I have raccoons, possums and a fox once in a while that come by. They rarely try to get in anymore, once in a while I'll see some scratching, but they hit the apron and go away.
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