I've flown over the Yukon a couple of times for six week trips down both the Kongakut and the Canning. Both times, I took a Smith & Wesson 629-1 to supplement my rifle, an '86 Winchester in 40-65.
Food was a problem. Fishing on both rivers proved spotty. Once on the Kongakut, about a month out, I decided I needed to test the revolver to make sure everything still functioned, and I headshot a couple ground squirrels. Ground squirrels were actually quite prevalent, and I wish I had a .22 pistol with me with something like CB caps. I didn't have enough .44 magnum ammunition to burn for no more than the value of the ground squirrel, and I didn't like announcing my presence to the world for no more meat than a ground squirrel offered.
I'm not that enamored with the idea of a handgun for bear protection. It can and has been done and will be done again, but I've seen too many large animals hit with a handgun to have too much faith in it. Killing the bear at close range is easier than stopping him. Still, I wouldn't want to be without the handgun. If my boat went down in a rapid and I lost everything but what I had on my person, the .44 magnum in an El Paso Saddlery crossdraw would leave me higher on the food chain than I would be without it.
In Canada, east of the Yukon, during a five month trip through the Mackenzie Mountains, I relied solely on a Remington 700 .35 Whelen. I would have loved to have had a handgun, any handgun, a Ruger Bearcat .22 would have been a godsend. One thing I won't do again is rely on just one weapon. Too much can go wrong with any mechanical device. It's a sick feeling when you hear something outside of the tent, the bolt's out of the rifle, a cleaning rod is in the barrel, and you have no other weapon.