Yes, they can fly over a fence. My fences are 5 ft high and I have 5 pens with fencing between the pens and many go over the fences into the other pens. I am planning on putting another 2 foot piece of wire to make the pens 7 ft high.There's also cow pasture around our area maybe I can have even just 4 chicken btw do they fly? I mean if they're not inside their coop will they fly over the fence?