I'm still in the learning stage chicken wise but I have a lot of experience trapping and hunting predators so I'd like to share a few things I've learned that will deter predators from getting inside your coops and runs. All are still in the trial phase with our chickens but so far, so good. A few behavioral traits first. Possums, Raccoons, Skunks, Mink, owls and felines are most active at night. Weasels, Fox and coyotes are most active within an hour of dawn and dusk but are easily conditioned to your schedule. Hawks and Falcons are most active during the day and will not hunt at night. They prefer open areas with the exception of a few northern species that prey on grouse. All mammal predators are territorial, you can use this to your advantage using urine or musk type lures for trapping. Foxes and Coyotes are often unwilling to enter confined spaces. Foxes, mink, felines and coyotes are ambush predators. They will tend to hang out in brushy areas nearby and wait for prey to come close before attacking. Skunks, possums, raccoons are omniverous and target chickens as the opportunity presents. Removing clutter, dogfood, birdseed and trash will deter them hanging around. Keeping a dog on the property, preferably a male one will deter canine predators. Construction: I drive a nail into the center and sides 3" high at the entrances to my coop and run, leaving the head exposed about 2". Racoons and foxes do not like the poke in the chest they get from this and will usually not enter. My wire is held to heavy timber with U nails rather than staples. Wire around run is backfilled with trap rock and dirt to discourage digging under. Doors are placed far away from any cover preventing a stealthy approach. They are pegged to holes drilled into timber with heavy timber spikes when chickens are put up. I have a radio in the barn tuned to talk set on a random timer to discourage conditioning to our schedule. My yard is kept clear of loose woodpiles, garbage, old tin, etc that would provide a nice hiding spot for raccoons or possums. I regularly patrol the yard and barn for predator signs such as tracks, droppings or trails up from the swamp to know if more proactive measures are needed. My coop is built with OSB fully sheathed to near the barn rafters. Ventilation squares are cut at least 2 feet above ground and covered with heavy wire. I also encourage the dog to pee around the perimeter of the chicken area. We have coyotes and fox nearby. Can't wait for trapping season.