You would be surprised what a hungry animal could do. But I would def be looking for any evidence of anything other than an animal getting in there! It always breaks my heart to see stuff like this. We just got an order of 21 one day old chicks and they will be staying in my brooder boxes inside my house for quite sometime.But this is hardware cloth, much stronger than chicken wire, and for the most part thought to be impenetrable to predators.
That's why we are all really interested to find out how the hardware cloth got ripped like that.