Food Storage Bags
Bear-resistant food storage containers, commonly called bear canisters or simply bear cans, are usually hard-sided containers used by backpackers to protect their food from theft by bears. more...
Bear canisters are seeing increased popularity in areas where bears have become habituated to human presence, and are required in some regions such as Yosemite National Park in the United States.
A bear canister typically weighs between 2-4 lb (1-2 kg), and has a storage capacity of 400 - 900 in³ (6 - 15 liters). The actual capacity in terms of the number of days of hiking food stored will vary with the appetite of the hiker, the selection of food, and the skill in which it is packed, but a 700 in³ canister will likely hold up to week's worth of food for the average hiker.
Construction
Hard-sided bear cans employ such materials as polycarbonate, ABS plastic, carbon fiber, and aluminum in their construction. An effective canister must resist both the tremendous strength and high intelligence of an attacking animal. Most containers are too large for a bear to simply pick up and carry away.
The lid of a canister is usually recessed in order to prevent it getting pried off, and tool use, or least an advanced degree of motor skills, is required to remove it.
At least one model of soft-sided "bear bag" is made from Spectra fabric. While a soft-sided container may prevent a bear from eating its contents, the food inside is likely to be reduced to puree in the attempt. A newer model, the Ursack Hybrid, comes with an aluminum stiffener that protects the contents more effectively than the bag alone.
Regulations
A small number of national parks and national forests require backcountry visitors to carry approved food storage containers. Backpackers who ignore this policy may face fines, property impoundment, or eviction from the wilderness. Rangers may stop hikers and require them to produce their containers for inspection.
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