We keep it very simple when dealing with preditors including feral "pets".
We have game cams at all the pens.
We also use ir cameras and video rec.
And simply review the footage. Day or Night.
We don't kill every animal that makes its way onto our property.
Preditors have paterns that can be monitored and prepared for.
Every vermin that has been eliminated has been guilty, and in many cases caught in the act.
The last dog that we caught, had a collar on him. (An animal with a collar is never killed)
We were able to catch him and put him in one of our sheds.
We called the owner and asked him if he was missing a dog.
His 2 year old shepard decided to not only tresspass, but to attempt an attack on my dog.
Who pretty much ate him up.
The dog owner was a little pi.... about his dogs condition.
So just to humor him, I invited him to look at a little video.
Even offered him a beer.
I took him into my office and showed him about 2 min of a video with his dog.
His attitude changed pretty fast, when the vid showed my MIl going out to investigate all the noise.
Which clearly had shown the shepards attack, and the response given.
Audio could be heard of her calling Teu (our Rhodesian Ridgeback) off the shepard.
Which was on his back, with Teu's mouth around his neck.
Beginning a process which only ends badly.
I think the dozen eggs I gave him when he left, smoothed things over.
He comes by now and then to purchase items from us.
His daughter loves our dog, she gives him hugs. (Rhodesians are great around children)
I just wonder what their shepard thinks, when he smells Teu on his owners ?
Not all people kill everything that enters their property.