Does hanging food really stop bears?

Bears can detect things, by smell, that most other animals cannot. OP sacks don’t work all that well because you cannot get them clean enough. A regular ziplock works well to limit the amount of smell, but does not mask or eliminate smells. Again, I put the bear hang high enough and far enough away from a branch that there is no hope of getting the bag without cutting the cord or taking the actual branch down (either by breaking it or by chewing on it.) Yes, they know it is there. But like other things in the forest, (squirrel nests, say) they usually ignore it. Continuing the example, they do not chase after a squirrel in the trees, even though a bear knows the squirrel and stash is there.

Ha ha, yes, they do go after salami, dried fish and cheese.

”  A regular ziplock works well to limit the amount of smell, but does not mask or eliminate smells.”

To support  Randy Martin’s post on the previous page:

To the degree you reduce the amount of aromatics that escape your bag and disperse into the atmosphere, you greatly reduce the chances of attracting a bear from farther out to come and investigate closely enough to home in on the source.  In combination with careful selection of low odor foods, a no cook protocol, double bagging with Nylofume bags, and camping away from popular areas, my experience has been that I have not had to deal with a bear in camp since 1979.  Of late, I have added a 3rd layer of protection, the large mylar zip lock bags the Ryan Jordan first introduced into the discussion some threads ago.  Careful hand washing before sliding the second and third bags over the first is mandatory, of course.  Otherwise, you are just propagating the aromatics outward to each successive bag.

Yes. It does limit the amount of smell or aromatics, thereby “tricking” the bears nose into sensing a smaller package. Again, they do not work all that well. I’ll be damned if I am going to go through a half hour, washing, bagging, washing, bagging, washing and bagging twice per day to limit odor “creep” from bag to bag. This is not really practical on a trip.

Use a different tree to tie off your cord, tie it rather high (4-6′) and use a rather dull colored cord that cannot be followed down easily. I have a orange/red/black cord that works well. Sometimes, I cannot see it;) Hanging your bag about 15-20′ up (a rather high hang) helps too. I usually select a branch that leaves my 35′ cord about 5′ off the ground. Anyway, bears usually sniff around in a 4-5′ window in front of them (ignoring any wind.) So, tying it high keeps the cord safer, low visibility keeps the cord safer, and tying off to a second tree keeps the cord safer.

If the opportunity presents itself, it’s always more effective to run a separate line between two trees, and hang the bear bag in between the trees, instead of simply hanging the bag off a single tree branch. While it’s a little more of a pita, its a better solution, and especially useful if I’m staying in one spot for extended days.

Interestingly, Andrew Skurka just wrote a piece on bear canister failures a few months ago. He offers a link to a spreadsheet of reported bear encounters in Yosemite  over the past five years. It really illustrates what bears are willing an able to do.

As far as running two bear lines, 1) between trees and 2) down to the bag, this is a bit ridiculous INMHO. It doesn’t matter if you have one bear line from a tree or from two tree’s. What *does* matter is the overall proximity of the hanging line to the bear bag. This is why I recommend a second tree to tie off to, and, tie it high, above the bears normal sniff range. You really cannot stop a determined, stubborn bear, all you can hope to do is slow his interest, feeding behavior down. Perhaps, giving you enough time to annoy him sufficiently to give up…loud noises, clearly aggressive stance, annoying rocks or sticks thrown at him, etc. In *NO* case should you attempt to retrieve the food bag or canister until he has left for good. That means waiting for a half hour, pretty much guarding your food, until you can safely retrieve it and rehang it or re-establish a safe area for the cannister. Do not forget that a Grizzly bear could charge you, and, contest ownership of the canister/bear bag.

As far as “trained” bears go, well, trained bears are trained bears. You should never ever allow trained bears to happen. Wild black bears are smart. They will not risk bodily damage for a single meal. Grizzly’s are different. They will interpret defense of a food bag as a challenge, they may just walk away. They might charge. Have a can of spray handy and ready to use *before* you head out to make noise.

Our summer plans are changing from Philmont – where they hang from a cable and tie-off to a tree, to somewhere in the Sierra.  We will likely need canisters.  If we didn’t I would still be torn between my Ursack allwhite and a counter-balanced (or PCT) hang with a Zpacks food bag.  I know it’s a Pita to hang, but it is the lightest option by far!

++ on using an OPSAK with any of the above.  I should probably wash it between trips, but I don’t see myself washing it on a trip unless I spilled food on it.  I should probably wash my Ursak or zpacks food bag as well.

Interesting item about the Yosemite spreadsheet is how many bear canisters went missing in the night.  Surprising, I never imagine a bear being able to carry the canisters very far, but it seems that is not the case.

People steal. More than one report here of people having their canisters tampered with.

“Yes. It does limit the amount of smell or aromatics, thereby “tricking” the bears nose into sensing a smaller package.”

If you do it carefully, the bear won’t sense a package at all from afar and thus not come closer to investigate.  That is the whole point.

“Again, they do not work all that well.”

And I’ve got over 30 years of experience supplying at least one data point that says it does work.

“I’ll be damned if I am going to go through a half hour, washing, bagging, washing, bagging, washing and bagging twice per day to limit odor “creep” from bag to bag. This is not really practical on a trip.”

It takes all of 5 minutes.  You wash once after the first bag and that’s it.  All you need to do is be careful when handling bags 2-3.  Note also that the bags are only one part of the protocol.  Anyhow, I presented the technique as one way to approach the problem, not as THE way to go about protecting your food.  To each their own.

“As far as running two bear lines, 1) between trees and 2) down to the bag, this is a bit ridiculous INMHO.”

If I’m going solo, or with a small group, it might seem over the top. However, the more “stuff” that needs to be hauled in the air, the easier it is to hit a line that’s I’ve suspended between two trees.

My first bear encounter was witnessing a juvenile literally “swinging” back and forth in a tree – about 15/20 feet up in the air. I wonder what the bear could smell from that height. Thinking that my bear bag is out of “smelling range” because it’s higher is misleading. What is a bear’s “smell range” anyway. I assume that scientists may have studied this, but how does one control all the variables to determine that: wind, terrain, age of bear, temperature, other competing smells?

Get the bag away from things that animals climb on. That’s why a a line between trees works well – ridiculous or otherwise. And obviously the higher the better – but I wouldn’t assume they can’t smell it. (This is how the Scouts have been taught for years. When it’s properly done – no issues.)

” That’s why a a line between trees works well – ridiculous or otherwise. And obviously the higher the better – but I wouldn’t assume they can’t smell it.”

The obvious issue here being that once bears have figured out the connection between rope and food bags, they will simply climb one of the trees and chew through or break the rope.  And they have definitely made that connection in parts of the Sierra.  I think what we are seeing in this thread is different solutins based on experience in different parts of the country.  Vive la difference!. :0)

Well, I have also seen a picture of a bear going hand-over-hand along a rope to get to a food bag. I have seen pictures of them upside down sliding along a rope to get to a bird feeder. A rope between trees wouldn’t work in these examples. If the tree you choose is climbable to a bear, he can easily climb out along a rope to get the food bag.

OP sacks are wasted effort. For 50 years I have been getting out and hanging my food and never had a problem. In every case, they know the food is in the tree (ha, including salami.) Sometimes, they stop under the bag and take a turn. They may walk through camp because there is a trail there. He is doing bear things as he should, just foraging around. OP sacks are contaminated without extraordinary precautions. Double bagging it simply means a LOT of work for a camper. The bear will still know it is there. As an article of a few years ago said, they can detect smells right through it. They used rubber gloves (inserted into the bag after using them) and double bagging. There was no difference in the test animal, a dog. A bears smell is MUCH better than any dog. No, I do not trust them and will not use them. I think I would rather spend the extra 5 minutes looking for a better tree.

Again, OP sacks, canisters, bear hangs, ursacks only slow a bear down. A determined bear can get your food.

do hanging bears stop food?

OP sacks are contaminated without extraordinary precautions. Double bagging it simply means a LOT of work for a camper. The bear will still know it is there. As an article of a few years ago said, they can detect smells right through it. They used rubber gloves (inserted into the bag after using them) and double bagging. There was no difference in the test animal, a dog.

The question is how much more does your Opsack smell than you?  Yes, the dog can smell the traces of food but is it strong enough for a bear to say “There’s more than just traces of food on the human, but a full bag of food?”

Well, I think a bear has other senses, too. Sight will tell him the overall size, once he has located it. Bears are not nocturnal, generally. But they do roam about in a bright moon, at dusk and predawn, too. They also can smell people, but again, they can distinguish between a bit of food on your hand and a bit of food not on your hand. They can discriminate smells much like we can discriminate light (a persons strongest sense.) A grizzly doesn’t care, of course, just different food types to him. No, I do not trust OP sacks, nor the time/effort involved in maintaining a clean OP sack on a week long trip. They may slow down a bear from a distance, but closer it is just another food bag. You still need to hang it, with or without an OP sack.

“OP sacks are wasted effort. For 50 years I have been getting out and hanging my food and never had a problem. In every case, they know the food is in the tree (ha, including salami.) Sometimes, they stop under the bag and take a turn. They may walk through camp because there is a trail there. He is doing bear things as he should, just foraging around. OP sacks are contaminated without extraordinary precautions. Double bagging it simply means a LOT of work for a camper. The bear will still know it is there. As an article of a few years ago said, they can detect smells right through it. They used rubber gloves (inserted into the bag after using them) and double bagging. There was no difference in the test animal, a dog. A bears smell is MUCH better than any dog. No, I do not trust them and will not use them. I think I would rather spend the extra 5 minutes looking for a better tree.”

It is becoming clear that we are dealing with different situations in different parts of the country.  I can personally guarantee you that any habituated Sierra bear will bring your bag to the ground in short order, if a ranger doesn’t escort you out of the back country first.  Of course, if a bear/dog is exposed to a bagged or, even, double bagged stuff sack of food at close range it will likely pick up traces of food and investigate further by ripping the bag apart.  What you seem to be ignoring is the fact that each additional layer of nearly OP bag reduces the amount of released aromatics that will bring the bear into camp in the first place.  Also, in the Sierra we often do not have the luxury of choosing from among a plethora of those mythical trees with perfect branches 20 feet or more up in the air extending 10-15 feet out horizontally and at least 4-5 inches thick.  Your 50 years of experience has led you to a method that works in your neck of the woods, but that neck of the woods is different than mine, and I will stack my 45 years of experience out here up against yours anytime.  Out here. Enough said.

“Bears are not nocturnal, generally. But they do roam about in a bright moon, at dusk and predawn, too.”

Perhaps your bears operate that way, but both of my bears encounters occurred in the middle of the night.  Again, resit the temptation to think that your local experiences have universal application.

I am really sorry you have such a big problem in the hills of California. All I know is what works. Nofume bags do not. Many of the canisters do not work. Bear vaults in particular are prone to being broken into. No, the OP sacks don’t help. If that’s what you believe in, then sure, go ahead and use them. It is Not my choice.

Nocturnal foraging by bears is not quite correct. They forage anytime they feel like it, but, generally speaking, they are far more active during the day. Some species do indeed spend nocturnal hours foraging, but not in the US. Generally, they are in the vicinity and know where you food is and simply take a nap, waiting for less activity in camp. It is known that a bear *will* become nocturnal living close to humans. Placing your food a long ways from camp (>300′) will often leave it open to a bear anytime, day or night. I have encountered them on the trail at least as often as I have seen them in camp, a couple times in my drive to the trail head. In one case, the bear would not move (eating berries in a patch,) I detoured way around him, bushwhacking for a half hour. The overall activity seems to be the deciding factor. (No, my pants weren’t brown, but my heart was thudding. I was getting worried that nobody would find my body…what was left of it.)

I really want to see the video of what happened to that bear after he chewed through the rope holding the birdhouse.  He probably slammed into the tree and the birdseed rained down on him – mission accomplished!

I always thought of bears as a Western mountain (like Yosemite) problem, because having grown up in PA and IN we just didn’t see them on the trail.  More and more I’m hearing of bear problems up and down the Eastern US – and not just in the back country.  Is it the news cycle, or is there a generation of bears becoming more comfortable in the near-town environments from FL to the North East?

Sierra = canisters for us next week.  We’re still not sure what trail head we are going to with our scouts, and although canisters aren’t required everywhere it’s an obvious choice if we are going to spend any time above treeline.

“I am really sorry you have such a big problem in the hills of California.”

Gosh, James, I truly appreciate your sympathy.  I guess the reports we’ve had here on BPL of equally severe problems out East are just more fake news?  According to the USFS and NP Service, canisters have been a huge success in the hills of CA, a very few instances of failure notwithstanding.  So, again I am left to wonder if maybe your conclusions about canisters are based on your limited experience in another part of the country.  Or maybe on another article?

“All I know is what works. Nofume bags do not……No, the OP sacks don’t help. If that’s what you believe in, then sure, go ahead and use them. It is Not my choice.”

Perhaps better expressed as “All I know is what works for me”?  You have a couple of articles about tests in an artificial environment to go on, and from what you have posted, zero field experience with the bags.  So, I’m inclined to respond that if you ‘believe’ that OP sacks are useless, don’t use them.  As you put it, they are NOT your choice.  Fine, that’s protected by the 1st amendment under freedom of religion.  But, please, don’t talk like you’re delivering the holy writ on the subject, because there are fair number of us out here who have as much experience as you, and have found equally successful ways to deal with bears, at least one of which involves Nylofume bags as PART of a multifaceted protocol.  In any case, I’ve contributed what I think might be useful to others in my previous posts, above.  They can take from it what they will, or not.  But for sure, no sense wasting any more time on this particular conversation.

“Nocturnal foraging by bears is not quite correct.”

You’re just flat wrong, based on personal experience and a lot of information from others I know.

Well, nylofume bags are simply wasted effort. A bear can smell through them, and/or the food smells imparted on them. Logic dictates they are a don’t care. (And yes, I did try a couple when they first came out ~25 years ago.) Using one does not stop smells. Not using one does not stop smells. I don’t care if you use one. Here is a discussion from several years ago https://backpackinglight.com/odor_proof_bags_study/
They are impossible to keep clean on a longer trip (I usually spend between 1-2 weeks out.) Washing your hands after retrieving food, then bagging it again is extra effort that does not stop smells. Some people use them as pillows, I think they have a strong desire to meet a bear face to face. I do not.

I would never preach to you. You are well set in your ways. I worry that others will try the OP sacks and ignore other more important bear hanging or canister rules you obviously follow to stay safe.

We have a few bears around that cause problems. Stephens Pond had a woman slice a bear snout. I was there the week before and had a group of bears following me for half a mile (till I scared them off.) Marcy Dam is noted for bears breaking into canisters multiple times. (The bear was even trained with rubber shot a few times and tagged twice, hence her name: Yellow-Yellow. She was not aggressive at all.) I was staying with my daughter near Lake Colden when she came through tried to open our canister, failed and moved on to the next one (in the evening of course.) She shooed with a little noise. But, this really only pushed her off to the next person…NOT a solution. I was down wind from a bear as he swam across a lake. He stopped at the shore line to eat a mussel and foraged for a minute looking for more. This was in the afternoon at Cedar Lake in the Moose River Plains area.

Nocturnal means bears forage primarily at night. This is not true. They forage anytime they damn well please but often during daylight hours in mornings and evenings, more crepuscular bordering on cathemeral. This behavior can change when in contact with people. Too reverse the logic, IFF they are foraging at night more than during the day, I would suggest there is a strong human presence in the area (an area I would avoid since it means an increased chance of trained bears.)

You’re just flat wrong, based on personal experience and a lot of information from others I know.

Very interesting posts in this forum. There is a lot of experience among all who have commented about food hanging and how to store foods properly in the backcountry. Here are a few comments from a bear biologist who has been involved in the management of bears for 35 years and has worked on the formal investigations on numerous human fatalities due to bear attacks:

• Most bears are wild and avoid humans and want to stay away from us.  Thus, the training humans about how to store foods when backpacking and training people how to avoid surprise encounters to help bears stay wild.
• Bears do forage at night and during the day. We have actually documented through radio-tracking that many bears are active during the day when in areas away from humans and the same bears will become totally nocturnal when they move to areas around humans.
• There are 2 basic behaviors of both black bears and grizzly bears that are specifically related to  humans:
  • 1) Habituation – this is the loss of normal fear/avoidance that happens when bears lose their fear of being around humans.  This can happen in or out of National Parks.  Habituated bears are relaxed around humans and do not flee or avoid humans.  Think of bears or along roads (bear jams) or trails in Parks feeding on natural foods or traveling and seeming to ignore humans.  Bears can get habituated by being around humans with little negative results or being taught by their mothers to feed on natural foods around areas with humans (i.e. roadsides).
  • 2) Food conditioning – this happens when bears obtain human-related foods like camp foods or garbage or bird/pet feed.  A bear’s entire existence is driven by finding food and remembering where its was found and how it was obtained.  Thus, once a bear is food conditioned to human-related foods, it will likely continue this behavior to look for this food or its source(s) again. Here we see garbage bears, camp checking bears, bears in bird feeders, etc.
• A bear can be habituated and not food conditioned, or food conditioned and not habituated.  Or, <span style=”text-decoration: underline;”>the worse case scenario</span>: a bear can be BOTH food conditioned and habituated.  Habituated bears are rarely dangerous unless people get too close to them – think tourists in National Parks trying to get close to roadside bears to take pictures. Habituated bears will not look for human foods in clean backcountry camps.  Wild bears will rarely if ever look for human foods in backcountry camps – they avoid humans.  <span style=”text-decoration: underline;”>Remember that most bears are wild bears</span>. Food conditioned bears that are not habituated are wary around people and may hang around camps where they cannot be seen (or homes with bird feeders) but not enter them when humans are present or visit camps or campsites after humans have left to check for food remains in messy camps.
• A bear that is BOTH habituated and food conditioned is dangerous to humans and bear managers almost always remove (destroy) such animals.  These bears enter camps with people present and walk right up on porches to get human or pet food or garbage that is accessible.  If you are in a situation where you encounter such a bear, leave and get out of there and report what happened as such bears can be dangerous to humans. Always carry and know how to use bear spray as the best deterrent when in bear habitat!
• Mother bears teach their young their learned behaviors. Thus, if a mother bear bear is food conditioned, she will teach her cubs to be food conditioned and to seek human use areas for human foods. The same thing goes for habituated mother bears whose cubs will be less likely to avoid humans (habituated bears rarely approach humans).
• It is important to recognize that once bears get food conditioned, they rarely if ever will stop visiting human use areas for food.  This is the basic reason we are all talking about food storage in backcountry areas. Proper food storage in the backcountry (and the front country) is the key to keeping bears wild and avoiding food conditioning.
• Bears can smell foods in camps or in hanging bags or in bear resistant food containers, even from a long way off.  The reason bears do not enter camps or try to climb up trees and get food bags is that MOST bears are wild bears avoid humans and human use areas and are not either food conditioned or habituated.
• Hanging your food (ALL your food) in the backcountry and keeping a clean camp with no spilled human food or pet food will keep most bears away from this human-related food and prevent them from becoming food conditioned.
• While it is true that a determined food conditioned black bear or grizzly bear can climb a tree and get a food bag if it really wants to, this will really only happen with a seriously food conditioned bear.
• All of everyone’s efforts to hang foods in the backcountry and keep clean camps is directed at one basic objective: to keep bears wild and avoid food conditioning a bear.  It is really up to all of us backcountry users to do our part to keep bears wild.  If we are sloppy and leave human foods about or available to bears, we will have changed that bear and made it into a permanently food conditioned bear that will be a problem to others who use the backcountry.  When we see bears that seek human foods in human use areas, or check camp sites after people have left, or try to climb trees to get food bags, this is because some other backcountry user has not done the right thing and made a wild bear into a food conditioned bear.  When this happens, we clean campers and food bag hangers face a serious problem not of our making.  Everyone has to work to do the right thing to keep bears wild and keep backcountry camping safe and bear problem free.

I am happy to try and answer questions about bears, human relations with bears, and bear behaviors if anyone has any.

@mapletrim – Well said!

I’ve read ”
<h1 id=”title” class=”a-size-large a-spacing-none”><span id=”ebooksProductTitle” class=”a-size-extra-large”>Backcountry Bear Basics: The Definitive Guide to Avoiding Unpleasant Encounters (Mountaineers Outdoor Basics)”</span></h1>
and found much of the same well-reasoned info.  I highly recommend the book and I think you boiled it down nicely – and clarified well the habituation vs food conditioning.  Methods may differ, but the goal is the same.  I get concerned when some are worried that their food will be stolen, because they will be hungry.  Think about the bears and keeping them wild, and your food will be there for you in almost all cases.  Have a backup plan to evacuate if it’s not.

One take away I had from the book, that is being debated here is the bear’s ability to smell food.  If I understand it right, the bear’s smelling capability is off the chart.  He will smell food near him, but if not food conditioned he may not care.  The book also suggests bears are naturally curious and will check out new smells (even new humans), but unless they are habituated they won’t come near the humans.

We all know there are habituated and food conditioned bears out there, but the various smell blocking techniques are limited (but I believe of > zero value).  Would you recommend Opsack, Mylar or Nylofume bags in addition to the bear bag hanging or canister or is it a futile effort?

Bob,

I am not aware of the differences in these products so I am not a good one to answer your question.  Bears can smell almost anything from a ways off no matter what the food is in, but as you say, most are not food conditioned and will not approach a place (camp) with humans present.  So, I am not sure if there is any functional difference between these products or the value of investing in them.

• “Bears can smell foods in camps or in hanging bags or in bear resistant food containers, even from a long way off.  The reason bears do not enter camps or try to climb up trees and get food bags is that MOST bears are wild bears avoid humans and human use areas and are not either food conditioned or habituated.”
• Here is the crux of the matter for me, Chris.  It seems to me to become a matter of how far off bears can pick up food odors, which in turn depends on what foods are involved, whether they have been cooked, how they are stored, and unpredictable factors such as wind and humidity over which I have no control.  I have traditionally hiked in very remote areas where bears are not habituated, and have come to depend on low odor, uncooked foods as a result of a couple of unpleasant encounters early on in my backpacking career.  To decrease the chances of odor dispersal even further I have, as posted above, stored them in multiple layers of odor reducing, not odor proof, bags, on the hypothesis that each layer reduces the amount of odor producing molecules able to disperse into the atmosphere.  At some point, this, in combination with a low density of bears in the areas I frequent, and hand washing before applying the outer bag layers, would seem to me to reduce the chances of bring a not habituated bear into camp to almost zero.  That has certainly been my experience.  I haven’t had a bear in camp in 39 years and counting.  Admittedly, I am an experiment of one, but the results would seem to support the approach.  I would appreciate your input on this approach, for the benefit of everyone following this discussion.

OP sacks of all types reduce the apparent size of the food to a bear. It does not stop smells (they can smell through it) nor does it stop/interfere with the odor once it is in the air. A poor analogy, but think of wearing sunglasses. You reduce the amount of light you perceive, but it does not effect your distance vision…”two different animals”- focus and light gathering. Again, this is a rather poor analogy, but easily followed.

Your success over 39 years is probably NOT due to OP sacks. You MUST use other techniques as well. Hanging, canisters, ursacks, whatever… I don’t believe bear specific OP sacks were even available 40 years ago. At least I had never heard of them, but that’s here on the eastern seaboard.

Smells are insidious to being contained. We had a biomolecular tester in the lab we used to play with. (We were at a nuke plant in the dosimetry lab.) On a high enough setting, you could detect food/human/plastic smells on everything in the lab. A cup of coffee would set it off LOUDLY from across the room. We could wipe a finger of coffee on a bench somewhere and locate it well after it had dried. A bears sense of smell is his primary sensory organ. He can smell through water. He often wanders down a trail oblivious to the world while he sniffs. It is certainly possible to walk into a bears body space without him realizing you are coming. I would say his sense of smell is damned near the testers upper range.

Washing your hands with water does nothing but remove food particles, oils remain to be transferred. Washing with soap will impart a soap smell. Yes, we tried that, too. An unscented soap (we tried the old Ivory,) rinsing twice, did nothing to stop the smell. It did, however, reduce the magnitude. It looked like an exponential or maybe a gaussian reduction. We didn’t bother digging further. Like I say, we were just curios about the detector before scanning for hot spots (microscopic high radiation particles in dust, etc., especially iodine & cesium.)