No collars on either of these dogs either. We have net wire fencing all around the property to keep our dogs inside and out of the way of cars. It is a quarter mile to a new gate that was opened so cattle could graze another 10 acre parcel that was recently bought by a family member but is only fenced with barbed wire.
This is the second time a dog has come calling and killed our chickens. The first time, a couple years ago, I was out of the country and he killed 8 chickens also. The Wife managed to chase him off and opened a gate to let him get back out. We never did find out where he got in at. This was before we put the gate in the north end of our property to access the newly purchased land where we suspect these dogs got in at.
I was just surprised that our German Shepherd didn't bark or something even though he was inside the house at the time, he usually barks when any thing or anyone comes close to the house. He loves to chase the chickens out of our yard. There is a personal gravel road that separates the house lawn from the field grass and chickens must stay on the field grass or my dog will chase them back to the road. He occasionally will catch a chicken or even one of the many Canadian Geese that we have free ranging on the property, but he doesn't harm them, just pens the to the ground, then lets them up to see if they will run again. If they don't run, he will leave them be. That could be why those mongrels caught so many as they are used to just squatting when chased and caught which didn't work with the stray dogs.
Funny thing about the whole situation, I only saw one chicken left after doing my business with the strays and she flew out of a tree, so I thought sure they had killed all 30 of them. I don't know where the rest were but later that day they started appearing from their hiding places. Those dogs could at least have killed some roosters instead of my hens, I think they only got my laying hens darn it. Now I probably need to harvest a few roosters, I think I have 6, way too many.