My next pistol (in a year or so...) will probably be a Taurus Judge (unless I opt for a 1911, but that's irrelevant as to this question). I'm wondering about its utility as a defensive weapon at close range. Specifically, at ranges close than 15-20 yards, would it be better to go with the .410 slug or the .45 Colt? I envision myself taking it out into the backcountry with me when hiking in case of wildlife encounters (bears and/or mountain lions) that could take place when coming around a turn in the trail.

Assuming either of these rounds is acceptable for such an encounter (and I'm assuming if they're not it's unlikely there exists a concealable pistol that is and I'd have to see about something as drastic as a Serbu Super Shorty...), which round would be better suited for the task?