You started a very interesting subject, there is so much to just where game will be, on given conditions.
Moose and deer, at least, do far more migrating than most people realize. Deer will easily migrate 200 miles to spend the winter in better areas. Just drive through the more open hills in northern Washington and Idaho and look at all the winter deer. Probably half of them are "our" deer. And believe me, the locals know the migration routes!
Moose in BC will move many miles to get to their winter range. The winter ranges change, as the decidious trees grow too large to be moose feed, so the moose find new areas. This was very pronounced in north central BC, before so much of it got logged and laced with logging roads.
In the 1950s there was a great migration of moose north of Prince George. They gathered up from the endless miles of heavy, green bush, running north west from Summit Lake. They travelled in a south easterly direction, crossing the newly built Hart Highway over a stretch running from about 5 miles to fifteen miles, south of Summit Lake. They wintered along the Fraser River.
This was in late November/early December, which coincided with the season, for any bull, being on until December 15. I have seen where as many as thirty bull moose were shot from vehicles, slowly travelling along the highway.
I think all the logging has changed patterns, but moose do not spend the winter in thick, green, coniferous forest. One could spend all winter snow shoeing through such country and not see asingle moose!