I have a chicken pen that I built with a coop. The house part is elevated and the pen is made with 1/2 inch hardware cloth. It’s about 4x8 8 feet tall with a 7 foot tall lockable door. I keep a feeder and watered there. This is surrounded by 2 6 foot tall dog pens. We have bird netting over the top. Believe it or not, a Rhode Island Red can get over a 6 foot fence.
We keep the door to the small pen locked at night. We let them free range in the big pen during the day. When we are at home we will let them out of the dog pen in the afternoons.
Everything likes chicken or eggs or their food. I’ve had coyotes in the yard chasing them during the day. If a coon can reach through the wire it will pull off whatever it gets ahold of. Rats will eat the food and eggs. Snakes will eat the eggs.
I put golfballs in the nest boxes. We had a snake swallow one my wife chopped it open and got it back.
Dogs will kill every chicken they can for fun.
I could send you pictures of my setup.