Possums can bite through reg. chicken wire. So can any preditor with intent. We had a dog one time that bite through hardware cloth as well. Reinforce the chicken wire with hard ware cloth on the coop. Possum have awesome teeth. Yuck. Yep they love cat food. If the stray cats here don't eat all their food they are the first to get it. I hate them. There was a stray hen when I first moved here and I loved the way she would sing and peck. One night they got her. At the time I didn't have chickens and did not realize the dangers they would be in. I know now. My hb says our chicken house is fort knox. Lol. Jean