You certainly did foster discussion -- lots more interesting comments from you and others.
Re the areas I go, most are popular High Sierra areas. Many are higher than bears tend to go, but I read stories that bears have been moving higher following food sources [Our food? Us? <g>]. However, many of my campsites are in prime, habituated bear territory. For example, in 1996, I camped in the hardened campsite area just SE of the Muir Trail Ranch. Other hikers told me a bear was visiting each camp site every night [and probably doing pretty well]. There were plenty of fresh tracks. Canisters were not nearly as common then, but the bear ignored mine [the old 3 lb Garcia model]. On the same trip, I rounded a bend above McClure Meadow and came upon a big old bear sitting in the middle of the trail a few yards ahead, watching some horse packers setting camp across a small meadow. He seemed to be speculating on what he would find there for dinner. He moved
grudingly when I yelled about my superior right to the trail, but only went a few yards off and continued watching the packers. My point is that there have been plenty of habituated bears for many years, but they [most] seemed to learn very quickly that canisters were not food sources. By contrast, I was in Vidette Meadows in 1999, where they have the large, steel bear boxes. We were not bothered at Lower Viddette, but a bear apparently spent a long night trying to get into a box at Upper Viddette. Go figure.
I should add that I am definitely not a stealth camper. It seems to work fine for a small number of skilled campers, but it would be a disaster if everyone tried to do it.
The main thing that has struck me about your [and other's]canister concerns re bear behavior is that the same arguments seem to apply to ALL other forms of safe guarding food, except possibly negative reinforcement.
Hanging hiding, or otherwise protecting food seems to present all the same problems, except that the bears get a better ratio of intermittent reinforcement. This makes it more likely that they will persist in going after hikers' food. While we are speculating, which seems more likely to be POed, the bear that never gets food from people or the one that usually does, but can't get yours on a given night? Part of the Sierra bear problem is that much of our camping is at elevations where there are trees, but none large enough to hang food properly, so bears have learned to go after anything in a tree and many have learned to get even properly hung food.
Similarly, in Tom Kirchner's example of bluff-charging bears in Center Basin, bear canisters do not strike me as the obvious culprit. Tom, are you [or Ryan] suggesting that we make our food easier for the bears to get so they won't become frustrated? How about dropping our food and running if we see a bear coming toward us? <g> And while Center Basin is not really off the beaten path, it is not one of the most heavily used Sierra areas. Your post sort of suggests there is a group of bears that is becoming agressive there. True? Or is a single clever rogue?
FWIW, I just checked the Wild Ideas [Bearakade] website
They claim no food has ever been lost to a bear, and have a picture of a September 2005 sign [supposedly from the Tyndall Ranger] describing an agressive bear NORTH of Forester Pass that has been opening Bear Vault canisters and swiped one person. Could this be the same story? If it is only one of several such bears, maybe it is a "trend."
My sense is the opposite of Tom's. Sixty years ago, when I first started camping in the National Parks and Forests, bears were MUCH more habituated and there were many incidents in the heavily used areas [car camps]. Back country bears routinely raided food, and they gradually got smarter as we learned better ways to protect the food. However, I have seen nothing to suggest to me that they are getting closer to "the Line" in terms of attacking people as prey, certainly not as a result of using canisters. Again, what alternative do you propose? We either give them our food, or we frustrate them a bit. And I don't think many bears are actually frustrated by canisters, at least not for long.
In the interest of full disclosure, I have my own agenda, and that is what set me off. I am anti the anti-canister movement. I have it from a usually reliable source <g> that some of the PCT through hikers and other ultralighters have been advocating ignoring the canister requirements. [I am glad to hear it you are not in that group, Ryan.] I am sure some get away with it without losing food. There is a problem [from the bears' perspective] -- so many hikers, so little time. However, it only takes an occasional reinforcement to keep the bears looking to humans for food. IMHO, the anti-canister approach is an anti-social effort by a small group who just don't care if risking their food has consequences for everyone else. It is a little bit like people who want to race their cars on the public roads.
But at least I don't think most super ultralighters advocate keeping their food in their tents [excuse me, "tarps"]. I actually encountered a Darwin Award candidate on a recent trip who asked my what my bear canister was. When I explained, she said she couldn't see the need for anything like that. She always kept her food safely in her tent. :-(