I can't help you in the "hunting" side of it, but I've done some extensive hiking and backpacking in Colorado. Water is going to be your friend, if you're not peeing throughout the day, drink more. Coming from sea level to that elevation can be difficult, even for those of us in shape. When moving try to keep a slower steady pace to keep from wearing yourself out. You'll cover more ground by keeping a good pace than by moving fast and taking breaks.
My must have gear for a day pack while hiking is
Plenty of water- I drink a lot personally, so I carry about 80 ounces, this is more than alot of other people would carry.
Maps of the area, Compass, and My GPS with extra battery- Some days I don't even turn it on, but I know I have it if I need it.
Good Boots and Good Socks- You'll be putting miles on. And it'll be on hard terrain, not farm fields. Take care of your feet.
Proper Clothing- Weather changes out there quickly, dress in layers and pack accordingly to your elevation
That would be my basics for a day hike, I also typically carry a first aid kit, a camera, my phone, and some snacks. I hope ya'll have a good hunt and I hope this helps a little.
-Jake