The connection between moose and logging.

I live in north western British Columbia, Canada, west coast, just south of Alaska. Old timers where I live say that back before the railway came north, moose were only found in the south of British Columbia, not in the northern inland coastal region where I live. The assumption is that the moose followed the railway north. But I was thinking about it, and it's not as though moose couldn't go north without a railway to follow, they move very well in the woods and are strong swimmers. No, animal populations generally follow food sources, so what changed? Well, this part of the world used to be covered in old growth forest. You know those old pictures where guys with hand saws are cutting down massive trees? That was my neck of the woods. Besides a few parks, most of the giants are gone now, it's mostly second growth here, but have you ever been in an old growth forest? I hope you have, it's really beautiful and really impressive to be among the giants. But one of the things you'll notice is how there aren't many shrubs and grasses, mostly just moss. I mean, there are shrubs, but not much in the way of grazing opportunities for large animals like moose. Logging cuts are a different story though, they're open ground where the plant life is dominated by young plants - a much better grazing opportunity for a population of large animals than an old growth forest. Thus, I surmise that logging is actually what brought the moose north, not so much the railroad, although it is true that railways do make traveling easier for many species of wildlife, as do logging roads. Just a theory, but I thought I'd put it out there. What are your thoughts?