This is my third year with my flock, and I have learned so much about predators. My first year, I started with 6 bantams and they free ranged my back yard freely. All I had was a chain link fence without any issues. Once they started laying and hatching chicks the first attack happened. A chicken hawk grabbed one of the chicks right in front me. So until I could upgrade my fence I would only let them out when I was home and kept and eye out. I didn't have any issues until the following year when 2 stray dogs found a way in through my fence in the front yard and found my chickens in the back and just chewed as many as they could catch a leave them there. Lost 10 that day in just seconds. So I did the electric fence and it worked. No more dogs and all seemed to be at peace again. Towards the end of the year I added a wooden fence to the backyard and had to take down the electric wire down for a bit. Then all of a sudden stray cats started showing up and were snatching my bantams because they looked like small birds. I built them a large run 20 feet by 60 feet using 6 feet tall welded fence with 2x4 inch rectangles. So that kept the cats out and eventually all was at peace again. Now these last 2 months I've had some losses due to opossums! They are able to squeeze through those 2x4 rectangles. So I'm about to re-install my electric fence again. Has anyone had success with this type of protection against opposums? Sorry for the long story.