From Andrew Surka's website
Bear-resistant canisters are mandatory in most places throughout the High Sierra, including many places through which the SHR passes. I hate bear canisters. They are heavy (1 lb, 15 oz for the lightest model, the Bearikade Expedition from Wild-Ideas), they are an added expense, and they are uncomfortable to carry (their cylindrical shape fits awkwardly in small packs, and their hard sides inflict bruises if not cushioned correctly). Moreover, I would argue that canisters are not necessary if you practice good bear country techniques: do NOT camp where you cook, do NOT carry overly smelly foods or items, and do NOT camp in established sites or near popular trails; DO stealth camp, DO carry your food in odor-proof bags, and DO burn your trash every few days in order to minimize odors. Bears are most problematic in high-traffic areas, which the SHR purposely and mostly successfully avoids.
However, if you are caught by a ranger and you are not carrying a canister, you can receive a hefty fine. Rangers do patrol the backcountry, though in lower frequency than they used to (thank you Bush administration), and they regularly do canister checks on passing hikers. I’m not aware of any guaranteed technique to avoid a fine, e.g. by raising legal technicalities against warrantless searches or questioning law enforcement jurisdictions, etc. Therefore, my recommendation is to carry a canister—not to protect your food from bears, or to protect bears from you, but to protect yourself from rangers. If rangers were not out patrolling, I would not take a canister and I would instead rely on the effective techniques I have described above. Buzz and I both carried canisters.
For more information, visit the following land manager websites: Sequoia-Kings Canyon National Park, Yosemite National Park, and Inyo National Forest.