Lived in Montana for a long time!
So, in regards to wildlife:
Foxes are all around, but rare to see- they run away- but they're also a real bright red color.
Lots and lots and lots of deer and rabbits. Everywhere. You think they'll run? No, you're in THEIR territory now.
Oh my god moose. They are bigger than anything you have ever seen. Bigger than that. You will not be prepared, they are terrifying. Luckily they stay far away.
Bears and mountain lions. They stay away from you usually, but do not attempt to find them or provoke them. You are in THEIR HOME HERE.
Bugs. Bugs everywhere. You'll think you've gotten the bug out of your house but it's back. Oh my god there are bugs in the walls, the ceiling, in the toilet, in your bed. They will always be everywhere. And they stink. Buy air freshener and get used to having a vacuum to suck them up, you'll be fine.
SQUIRRELS. SO MANY SQUIRRELS. EVEN ON A MAIN ROAD THEY ARE THERE.
In the summertime, even in northern Montana, YES IT GETS VERY HOT. Not triple-digit weather, but you definitely are not in the snow all year round. It's the worst. If you don't have an air conditioner, GET ONE> It doesn't get cooler at night. And more bugs. An ungodly amount of bugs and deer.
It is the most beautiful autumn you will ever see in your life. Those cliche orange and red and yellow poems about leaves- it's more vibrant than that. There are leaves and squirrels everywhere. Mountain lions WILL steal your dog if you are not observant. Stock up on winter gear.
And pray.