On the issue of using inexpensive coil spring traps, no argument from me on that. If you have them and have them prepped and ready, and know how to use set them (consider cmom's experience as exhibit A) they can be highly effective. As indicated before, I firmly believe the use of these is within the grasp of 90% of the folks reading this, but again, there is a learning curve. Both in trap acquisition, trap prep and trap deployment. That doesn't happen overnight. If you decide to go that route, you had best get started now so you will be ready when the time comes you need them.
In post 3 of this thread, OP mentioned they had already hired a trapper.....presumably an ADC person or at least someone with skills and knowledge, and he missed. OP themselves had already set a live trap and 9 "jaws" traps.....whatever those are....and no luck. So on it's face, a bit tougher nut to crack than folks might think.
But which trap to use wasn't my point. Concept I'm stressing is to take advantage of what the animal is doing so as to nab him.
Here is a short video clip of a bobcat that is after a chicken.....
He has pretty much thrown caution to the wind.......he would be pretty easy to trick into going down a tunnel (cage trap)......or watch where he places his feet as potential locations where you might place a coil spring trap. Keep in mind, you need to get him to place is paw on a specific target the size of the end of a soup can. Put the bird right there.....and you can do it. And to be clear, we are NOT exposing the bird to any risk of harm. It can be set inside a cage or pet carrier, inside the coop or run. Placement is what we are after....just feet or even inches away.
There is another variation on this theme......
For this video.....go to the 2.0 min mark......and notice how he has set the cage trap INSIDE the coop.......access is through the open pop door.
And yet another variation on the same them...
And keep in mind, while all these videos were showing bobcats, the concept remains the same for other predators as well. A fox, a coyote, coons, minks, etc. Traps and presentation and placement of the traps differ, but concept is the same. Live chicken is the bait and it is right there in front of them.