I made a birdfeeder out of a plastic juice container a few weeks ago. Haven't seen very many birds come to it, but the seed was slowly diminishing. This morning it was suddenly all empty. I suspected a squirrel. When I lifted it down to refill, noticed the wire I fashioned into a loop to hang it by was a bit tangled, made me guess squirrel again. It wasn't until I brought it inside that noticed there was damage. Something had chewed the opening deeper and wider.