I could never live there; heck, I wouldn’t live anywhere that even had mountain lions. You’ll inevitably find some dope feeding them (even when it is illegal), and even without that these are wild animals that are carnivorous. What does a shotgun do against a grizzly? I guess more than it would do against a polar bear...
A 12 gage loaded with three inch magnum bear slugs will kill anything that walks in North America. 00 or 000 buckshot has also proven very effective against even the largest Alaskan Coastal Brown Bears (The Grizzlies larger cousin).