I make sure my bag hangs far below where a coon or possum can reach. A bear, at a minimum of 100 lbs. is one thing out on a limb, a little critter, another. A bag snugged up close to a limb is fair game to gnaw on. I've heard of bears tugging on a dangling string until the stick broke, but not first hand. They will chew through a tied off line. Where you have habituated bears, canisters probably are the answer.