Hi! We have 5 Black Sex Links hens and a Black Copper Maran rooster. Lately, the hens have been going nuts! They free range during the day and stay around the house, but recently they have been coming onto the back porch and squawking loudly and pecking at the back door. The other day one of them actually jumped up and hit the window. This is the 3rd chicken that has "gone crazy". The other 2 that started doing that disappeared a couple of days after it started (one at a time). I go into the woods around the house to look for them and they are just gone. The other chickens all stay together with the rooster - except the one that is nuts. She stays by herself. Is there a parasite or mite or worm that can cause this? Are they going off into the woods to die? We started out with 8 hens + Red, now we are down to 5 plus him. I'm concerned that this could spread to the other girls. We keep the coop clean. Should we stop free-ranging them? We have a 20x30 pen plus the coop area we keep them in when we are out of town - I just hate keeping them penned up if I don't have to. They seem to love roaming all around the property. Any suggestions or insights are greatly appreciated.