I had gotten 23 new pullets last week. 3-4 months old. Tight fence, they can not get out it and nothing has gotten in. Too small for raccoon, possum or such to get through the fence. It is 48 inch with hotwire at top. No holes in fence, no holes dug under fence. As of today, I have maybe a dozen of the pullets. Where in the world did they go? No bodies, no feathers, no body pieces have been found. I know raccoons got 5 of my older chickens, cause we found the carcases with chest ripped off and no insides. But they were not in a small area like the pullets. They were on 2 acres and raccoons could get onto it. Have since moved them and they are now behind tight fence and in about 1/8 of an acre. Have traps set out for raccoon, possum, etc. Live traps, but we do go ahead and kill them once trapped. Live trap in case something we don't want to die gets in it.