Bear Canisters
Bear Sense
Many people consider bears a big problem when doing hikes like the JMT. In fact, we didn't see a single bear in our three weeks on the trail. There was a bear around two of our camps, but we weren't bothered in either case. Both camps were near areas of human activity or concentration. Using Ray Jardine's “stealth camping” technique may be the best way to avoid bear encounters, but it is not always convenient. When using established campgrounds, there are often “bear boxes” available. These are big steel containers that are chained to trees. Bears absolutely cannot get into them. We used these a few times and usually put all extra gear into them as well. Some good info including the locations of bear-boxes can be found on this Sequoia Kings Canyon Park site.
Remember, bears consider things like tooth-paste and medicines to be edible, and evidently even tasty. Avoid carrying things that have strong odors, like cosmetics, and keep any possible bear-attractants out of your tent. If you can, eat far away from where you sleep. If a bear does get your food, don't try to get it back; it's not worth the risk. A number of bear-safety tips can be found at the Bear Etiquette site.
Black bears are common in the Sierras, and easily become habituated to human activity. Hikers don't hunt or harm bears, but may be a source of some tasty food. From the bear's perspective, there's no downside. Once a bear loses his fear of humans, and begins to see hikers as meal-tickets, that bear becomes a “problem.” Black bears that become aggressive get reported and are often killed. Forest Service personnel would rather not do this, but they don't want hikers attacked either. Therefore it has become a wilderness policy not to feed wildlife. This means it is the hiker's responsibility to prevent bears, and other wildlife from getting your food. In the past, various methods of securing food in trees were advocated. This has proven ineffective. Bears are very resourceful, and have managed to get even well-secured food caches. As a result, most wilderness agencies recommend the use of bear-proof canisters. They are required in some locations on the JMT.
Yosemite Park provides rental canisters for $5 for up to two weeks, or you can bring your own approved canister. The Garcia bear canister is popular and widely available, and is the one you’ll get if you rent in Yosemite. It is cheaper than some others, but a bit heavier. We used Wild Ideas, Bearikade Weekenders. These are a little bigger, and lighter than the Garcia product, but more expensive. Their website says that this canister will hold up to six days worth of food for one person, and we found that this was accurate. You have to really compact your food though, but this is generally true of any canister. The BearVault is a little bigger and heavier than the Bearikade, but priced only a little more than the Garcia canister.
The Bear Keg is the heaviest of the approved canisters at over 3 lbs. It sells for about $80, about the same price range as the Garcia, and BearVault. Manufactured in Montana, it seems to be aimed at protecting your food from grizzly bears. Of course, if a grizzly bear is hanging around, you might have bigger problems than the loss of your food! There is one non-canister food-protector available—the Ursack. This is the lightest solution at about 8 oz. However, to be legal, you must add an aluminum insert for a total cost of about $85. Even so, this combination is only conditionally approved at this time.
There are, of course, trade-offs with each of these products. The Ursack is the lightest, even with the aluminum insert, but as a practical matter, they have to be hung just like any non-secure food bag. A bear that successfully pulled one out of the trees could carry it off, even if he couldn't get into it. The canisters are all ground-based solutions. That is, you place them a distance from your camp on level ground. If a bear finds it, he won't get in and won't be able to move it except perhaps to roll it around a bit. All said, I would recommend the Bearikade. It's well made, easy to pack and use, and will last many years. You'll save a little money on some of the other canisters, but carry the extra weight forever!
Insects