Of the two you listed, I would recommend the rifle. Having used slugs on whitetail deer, I was never impressed with the horrible sectional density. Since you have some time before you come up here (where abouts, BTW?), I would suggest a little penetration testing: take two 5 gallon plastic buckets, fill them with sheets of newspaper and cardboard. (75/25, keeping everything nice and flat), then top them off with water until saturated. Snap the covers back on, and duct tape the the two buckets together, lid to lid. Shoot at the base from about 10 yards away so that your bullet has the opportunity to travel lengthwise through both of them. Let us know how well they penetrate.
I personally carry either my 329PD w/ 265s, a .30-06 w/ 200s, a .45-70 w/ 405s, or a .375HH w/ 270s. It all depends on how far I am hiking that day, and the perceived likelihood of running into a bear. In general, I am lazy and go w/ the .44 because it is lightweight, and bears are typically nice to me.
I also carry spray in addition to a firearm when fishing.
Best of luck, and I hope you have a great time fishing up here. Stay safe.
