I'm surprised there wasn't anything mentioned about the effects of predation. They absolutely know when the regular human hunting seasons are and adjust their local migration accordingly - they'll be in high mountainous areas one day, then down in privately owned and farmed bottom land during the season, and back up the the elevations when that is over. I'd be more interested to see the effects of the wolf packs on their migration, which from my anecdotal experience affects their location far more acutely than the environmental conditions.