It's not a complicated issue, really, for me. My inclination is SSS, however, from all the discussion here, I wondered if I should give a warning rather than just kill the dog. Guess the warning should come before I lose a bird, not after. I have spent thousands over the years to confine my dogs to my property while others allow theirs to go wherever, whenever. There will always be people who think I'm an ogre for even contemplating shooting someone's dog, but once a chicken is dead, it's gone. It didn't get a second chance and neither should the dog, though it's the owner's fault 100% for not confining their animal. I'm someone who believes that ALL dogs should be fenced. If someone cannot afford a fence, they shouldn't get a dog, period.
As far as neighbor relations go, if they cared about my family and being a good neighbor, that dog would be contained and never allowed to set foot on my land. Pretty simple really. Wonder whether I should warn the neighbor that the dog was on my land today or just shoot it when it comes back.