Just what lawman's first post is what I have personally experienced.
I have cleared out hog populations with a rifle and night vision in 6 months with no traps. Did I kill them all? No but they do not know how to deal with night vision, suppressed rifles so the leave the area.
- Traps they learn.
The fear of the boogeyman will keep the older ones out for years and years.
I have satellite pics to prove it.
With spotlights when there is no light there is no boogeyman and they will return.
To keep them out with nv/ thermal suppressed hunting leave the alpha sows alone all others are targets
As far as the trapper
the ones in the trap are his and the hogs outside are fair game