Despite what the other idiot said if you have chickens you will have predators and if AIR can get in your pen they will eventually find a way in. Since you mention it ate the egg you left that points to racoon or possum and since you haven't caught it yet I'm thinking racoon. They are VERY difficult to trap; if you've caught them in a cage trap before you were lucky. Possums are pretty stupid and trapped easily. Usually once the offending animal is neutralized you are ok for a time. My chickens now roost at night in houses with floors and I close them up, but you still have to have ventilation so there are windows which are pretty high off the ground. It doesn't happen often, but there are times when a racoon gets in the house through one of those windows(may be once a year). The offending animal is neutralized and we have no more problems for a long time. My best defense has been my dog who barks at every noise!! Real carnage happens when I forget to close them up (which after one night of total losses I don't forget any more!!)
Can't believe DNR wants to know the animal BEFORE you trap it, LOL! Oh well..... I don't remember them asking me that...
I believe the reason the predator is no longer getting in (after eating the egg) is that it doesn't see/smell them in there at night? Why work at getting in if there isn't anything to get. I bet if I left them in at night that predator would get in again.
I am trying to predator-proof a 13'x26' pen with a roof. Not just an enclosed roosting area for them to sleep at night. I think the chickens do better roosting in open air Spring-Fall. So part of my problem is that the pen is so large that materials for hardware cloth alone can be high.
Hopefully soon I'll have the trail cam to SEE what is coming by. The fact that they want to KNOW what it is before I trap forces people to a) stay up all night waiting to see what it is, b) install a trail cam to see what it is, or (more likely) c) trap it then call to say they SAW a raccoon, all the while they have the raccoon in the trap, then they have to wait until the next day to say come get the raccoon? So the critter stays in a cage for potentially 2 days (or more) which is unfair to the critter (and probably illegal).
Only caught stray/feral cats the first 2 days then nothing. Stopped setting the traps. I don't want to LURE wild critters to my property by providing baited traps.