so for the 7 JMT hikes I did before canisters were even invented, I was just imagining my food was safe, and the bears that tried to get it were just the stupid kind?
Actually, probably that was true. There's likely some relationship of bear & hiker density. At a certain point, bears figure it out pretty quick. I was a major fan of counterbalancing for a number of years. And, not to be immodest, but may be a co-inventor of it. Mead & Tina Hargis and I developed the method in the early 70s in Little Yosemite Valley when we were rangers there. (A biologist doing her PhD credits us with it anyway). We started trying that after bears figure out how to chew through the ropes when they were just tied off to a tree.
We also tried cables on pulleys, static cables, old steel outhouses and electric fences. It's a bummer we didn't have more old steel outhouses, but they might have worked. Bears figured everything else out, though they at least reduced the chances of losing food.
Once you're in an area where bears are habituated to people's food, they'll just keep trying to get it. No matter how well it's counterbalanced, it's got a high potential of failure because:
1) a bear will get out on the limb and grab it, or
2) a bear will shake the branch enough that one side will work up and the other down where a bear can grab it, or
3) a bear will just spend the whole night chewing through the branch. I've seen them go through 4" branches.
In areas where there's few bears &/or hikers, you're probably OK for awhile (that is, over several trips). Once a bear starts to try, it usually takes them only 3 to 6 tries to become successful enough to get food a majority of the time.
As with anything else, if there's enough natural food around and not competition from other bears, they're more likely to stick with that. When there's more bears, &/or food is scarcer, you become the best game in town.
In Little Yosemite in the 70s, we had around 3 to 6 bears per night in a couple of square miles. An incredibly fast learning curve to watch. The same would be true in the Woods/Bubbs/Kearsarge area by the 80s; more than occasionally Crabtree/Rock Creek and other areas like Pear & Bearpaw.
Really amazing animals.
g.
