I'm going to apologises in advance cause this most likely will be long but I need y'alls opinion on who done this. First my set up is 2 12 x 12 horse stalls attached to a fairly large fenced in yard. My birds (16 chickens and 14 ducks) are locked in separate stalls at night butv allowed freerange of the fenced in area from 8 to 8 (during daylight period). This has been the set up for 2months with no issue. I also have a 7 yr old obese black lab that I've owned his whole life. He spends 99% loose he's very loyal. So here's what happened. I let everyone out at 8 am went back inside to deal with my kiddos. Went back out at 10 am with treats. My Chihuahuah been on the back porchon his run the whole time within few of the coop and he goes bananas if there is anything strange in his yard. I firston the outside of my coop beside the barn I find my little roo dead. I round the corner to find dead chickens all over my coop with minimal damage no evidence on any of the 15 corpsesthat the killwr tried to eat them. Whomever did it left a fat dog whole leading under thegate. Where wire had been torn up!they only got one duck the others were cowering in the open stall and whatever it waswas gone and left them by choice. There is nodoubt in my mind the culprit was my dog. I think that cause what other preditors, come out in day time, would slaughter all the chickens but not the ducks, and without eating/ mauling/ or stealing them for dinner. There are some (ie dh) who think it was a random predator because the dog had behaved for si long. But 4yrs prior said dog was caugyt killing neighbors chickens before we moved. What are y'alls thoughts?