I'd rather placed this game play question in the game play questions sub forum...
Passive hunting is the most efficient way to hunt, in my experience. It takes some work to set up, but once done you get time over for other things.
I only (occasionally) hunt big game actively (this does not count removing pests from my farm plots or my homestead) when my traps have been dry for an extended period of time, and "big" in my view is elk, reindeer and wild boar (bears are large, but they're also dangerous, so I avoid those. Wild boars can be dangerous as well).
When hunting large animals I typically look for a places with a good view, like hills, or open terrain like mires to see if I can see any in the distance. Otherwise I walk around zooming into each tile to look for animals or tracks (zoom in, look forward, turn 180 degrees, look, zoom out, turn 180 degrees, move one time, repeat). Any reasonably fresh tracks from large game can then be followed (assuming reasonable tracking skill), although I give up if the area is riddled with tracks crossing back and forth.
Also, I try to avoid spruce infested terrain as the visibility there is poor, but when I track animals passing through such terrain, well, I follow, but I won't look for new game there.
In short, about the same techniques as Privateer uses.
Animal abundance varies over time, but different animals have an affinity for different kinds of terrain as well.