I live in the Colorado mountains, and here is my 2 cents. Leave the bear spray at home. You are more likely to be struck by lightning than to suffer a bear attack. Besides, you are wearing a sidearm, in case you are a walking kismet.
As for 2 legged predators, rather than a predator with a leg in each corner, carry the sidearm in the method that is most comfortable for you. Seek retention holster since hiking and climbing are in the mix. Use the handgun that is comfortable enough you can wear it all day, one that can withstand the dirt, dust, and moisture, and in a cartridge you are effectiv with. In the space where the bear spray was going to be, throw in some mags or speed loaders. Me? I carry a 1911 platform in 10mm oe 45acp with plus p duty ammo.
