"Silence"
Using a silencer on a larger caliber weapon is obviously best,(but then there's generally the "laws" to think about).
Using subsonic .22lr rounds are certainly a very good way to go,(on most smaller game). I have many types of this, but smaller rounds such as the .22lr do require some practice as the shot placement can be critical.

I have hunted with crossbows, compound bows, and recurves,(composite and soild-carved), and I find these have a very good use and overall applications for most game, big, small, and even foul/birds. Probibly the most versitle would be the crossbow or compound bows due to the power.

Trapping is excellent, but it can be far from "silent" unless you know how and plan this as the goal.

As with all the above, silent hunting is an "Art" that requires much thought and planning. Nothing is perfect, but all the above can be done with very good results. As with all "Arts", they require much practice, thought, and planning.

IMHO, IHTH.

Michael