Just a suggestion:
Recently I was reading on Wikipedia about the sort-of-mythology created by lumberjacks in the US and Canada. In particular I really liked the variety of animals they invented:http://en.wikipedia.org/wiki/Fearsome_critters
If you don't mind slipping away from realism somewhat, it would be really cool if you included some of these in the game.
I hope you don't take this as me telling you how to make your game
I get unreasonably worried about that sort of thing. Like I said, it's just a suggestion.