One key item that will come up on each hike you look into will be bear bags or bear canisters. These are required on the trail to ensure you put your food in a safe location where animals, like a bear can't get to it. This is important to you and the bear equally as you don't want to lose your food, you don't want a bear in your camp and if a bear becomes dependent on human food they will put them down.
The benefit and reason you use a bear bag or bear canister is to ensure bears don't get to your food. Where a bear bag will be hung from a tree, the bear canister is a ground container that is able to withstand bears attack.
Now I am pretty sure you don't want to end up seeing this guy below us while camping because you left food in your tent! Lets take some time to go over why and when you need a bear bag or when it is more appropriate to get yourself a bear canister. Do note that some hike require bear canisters for at least portion of the thru-hike and it does weigh significantly more!
Typically a bear bag was simply something to hold your food out of reach of wild bears. This usually means finding a way to suspend it from a high branch, and in this instance it's usually sufficient for the bag to be waterproof.
Since they hang in the branch you need to keep in mind that this could let water in through the opening. Some people have taken to hanging theie bags "upside down" which helps to prevent rains ability to get in through the opening. Of note, be sure to tie them securely closed if you do this!
A true bear bag kit setup is combined of multiple parts which include a bear bag rope and weight, I prefer this weight and line combo pack, and a carabiner. These are what make setup and take down much easier and faster, many will say they can use a rock instead but this means you must find a rock and hope it works. This also means each time you go to setup you will have a new stone weight to find and throw, instead of learning one.
Most people will suggest you have to purchase and that you need an odor proof bag. From my research I can't find any rule that states this as a fact, other than PCT and rules for specific sections where canisters are required.
While not necessary I would like to say it will help to keep smells under control as you will have less bear traffic but it isn't a requirement by law. Now I don't want to see a bear so I made the small investment in this and it has been working wonderfully!
Considering that bears can smell soup inside of a can, or a footprint that was left weeks ago, it’s highly suspect that a plastic zip-top bag does much good at all.Pacific Crest Trail Association
There are different methods for hanging, but a common one is the PCT method. This is the one you will hear on most YouTube channels as it is pretty light and easy to carry the necessary gear. NPS recommendations
To briefly summarize the method:
If you aren't a big fan of burning time trying to hang a bear bag you can instead use a durable Ursack. We recommend this Ursack bear bag as at 8 ounces it can hold a weeks worth of food for when you are trekking as they hold up to abuse well.
An Ursack is a Kevlar sack designed to resist tooth and claws from bears. You instead only need to leave it on the ground and loosely tethered to a tree which is more to prevent the bear wandering off with it.
This is going to be much more efficient for your time instead of a bear bag and less weight than a bear canister. The only large downside to an Ursack is the bear could break the tether and steal the bag, or he could crush all the food together into a pulp inside the bag making any food items a mix.
A bear canister is used on some portions of the PCT and other long distance trails. Many will not carry a canister until where it becomes a requirement, instead using a bear bag up until needing to change. Once through the required area the thru-hiker will change out again for the bear bag to drop weight.
The lightest bear canister I could find is here at 2 lbs 9 oz, they are very bulky and I would agree with using it for only the necessary time where law requires it. Otherwise I would carry a bear sack or an Ursack to save me weight and space.
You should avoid packing along foods which are very aromatic foods such as bacon or fish if not in a aLOKSak or other odor absorbing bag. Whether these are raw or cooked, these highly aromatic foods will attract bear attention. Never, ever, bring food into your tent or store food in your tent for these reasons.
Many people think that a air horn is helpful in scaring away a bear. Unfortunately this is unproven and can leave you unprepared for the chance encounter.
Instead you must stand and face the bear directly. Never turn away, run away, or approach the bear. Spread out and try to make yourself look as large and imposing as possible by opening your arms wide. Also try to make as much unnatural noise as possible by yelling, banging pots and pans or using other noise devices.
I was able to find that black bears and grizzly bears are not or have not been shown to be attracted to the odors of menstruation, according to a recent Yellowstone National Park report. Food was rated as much more important of a temptation for bears.