When I was stationed at Whitefish, MT wildlife played a big part of the local news, especially "The Hungry Horse News."
Whenever I could, I'd patrol the road that runs from Columbia Falls, MT to the border. It was about a 50 mile long road that started as a nice paved two lane and ended up in a one lane jeep trail.
I'd always see a variety of wildlife on that run. Everything from Mule deer to Elk to Black Bear, Moose and even one very large Mountain Lion.
The POE (Port Of Entry) was only open 3 months during the summer with a husband-wife team manning the U.S. side and one Canadian Customs fellow on the other side of the border on two week rotation.
One of the Canadian Customs guys was an ex-RCMP member who had quite an interesting career. Not in the "shots fire, we are in pursuit" kind of way, but with wildlife, especially bears.
Whenever there was problem bear either he or his partner, or both would get called out. He really had some interesting stories and when asked how many bears he have to dispatch in a given year he answered, "The most I had in one year was 36." (mixture of Black and Brown bears)
I figured he'd be a real expert on "bear medicine" so I asked him what he used. He said that after some bad experiences with rifles he used what the RCMP recommended which was a 12ga. shooting xxxx. (I can't remember the name he used.) He really has no clue what it was, but each visit he'd walk over and tell me more bear encounter stories.
On one occasion there were two adult Griz running folks off a dump on an off-shore BC island. To make a long story short, he walked out onto the dump, provoked a charge and at 10-12 yards fired two rounds at each, dropping them both. Amazing.
It was driving me nuts. After spending my life hunting and shooting as well as serving as a Firearms Instructor at the US Border Patrol Academy at F.L.E.T.C. for 9 years I had to find out what "xxxx" was that worked so well on bears.
He added, "I don't know what it was, but it sure worked. The thing is, you really had to be close."
One day when I was doing a record check with the RCMP on a fellow I had picked up I asked them what the heck "xxxx" was?
Their reply was, "OO Buck." I was indeed surprised and that day I gained a new respect for 12 ga. "Double Ought".