Years ago, I learned about the futility of trying to kill my way out of a problem animal issue. I thought I was making a pretty good dent in the local starling population. I could easily whack several hundred over the course of month. Then one day I happened to drive past the area where all these starlings were roosting at night and observed numbers maybe exceeding a million or more. It suddenly dawned on me there wasn't that much lead on the planet to kill them all. I wasn't making any dent in anything. I hadn't even scratched the surface.
The same thing exists in the predator threat most of us face daily. If one animal is causing us problems, we might be able to take him out, but that is only a short term solution until one of his cousins steps in to take his place. So in this constant battle to save birds, you may win, lose or fight to a draw. But the threat never goes away. Short term solutions don't solve long term problems.
I'm a big advocate of electric fences, as those have allowed me the option of not having to accept losses and whack animals. An electric fence is very much like the goats blood Moses and his cohorts placed over their doors.......and signaled death to pass them by.
For me, the battle was over before it began. I use the same strategy Judge Roy Bean gave Bad Bob. I never give them a chance. It is my intent that they lose every single time they try. That is my long term solution.
Having said that, in the event you do have a problem animal, sometimes there is a need to step in and stop the carnage. Rid yourself of that short term threat from one single problem animal until you have the time, funds and knowledge of how to do better to protect the birds in the future. In short, develop your long term solution. Ultimately we should all start out there, but some don't realize how good some predators are at getting past our defenses. We learn the hard way and our birds are the ones paying the price. For some, you have to evolve and learn and it may take time to get there.