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How Strong Is A Bear’s Sense Of Smell!

A few years back we were parked for the night at a campground. In the middle of the night, the bear crawled into the back of the pickup truck and ran off with a backpack.

Even though there wasn’t any food in the pack, he smelled the lotions, biodegradable soap, and chapstick. It got me thinking about how strong the is bear’s sense of smell, so I decided to investigate.

A bear can certainly smell all the items that you keep in your tent. These include lotions, insect repellent, deodorant, soaps, shampoos, and of course, food. The bear’s sense of smell is roughly 2,100 times that of humans. In other words, the bear can smell up to a mile or two without question.

How strong is the Bear’s Sense of Smell?

According to The National Park Service, a bear’s sense of smell is difficult to measure. However, some studies and anecdotal evidence conservatively estimate that a bear can smell up to one to two miles away. Some groups speculate this to be much larger depending on the weather, temperature, humidity, and terrain conditions.

In a personally written account by author Gary Brown in his book The Great Bear Almanac, A bear can smell a ‘deer carcass three miles away’. But why do bears have such a strong sense of smell?

For starters, bears are very large animals who need to conserve their energy to prepare for the lean winter months. So, it suits them to have a keen sense of smell to keep their efforts in check when out foraging. Because, as you know the bear spends all day long walking to and fro looking for edibles. It just makes sense that she does this efficiently.

What Is The ‘Science’ Behind A Bear’s Super Smeller?

european brown bear snout
European Brown Bear Snout

To set the stage a bear has a very large and long snout. A snout, distinguished from just a nose, includes the bear’s nose, mouth, and jaw. These anatomical masterpieces work together in detecting food for the bear.

Let’s take a look. The long snout has two purposes. To detect odors and warm and moisten the inhaled air before sending it to the lungs.

The long snout contains millions of odor sensitive nerve and tiny muscles used to bend and point the bear in the right direction. Also, it contains the snout contains a nasal mucosa (moist mucus membrane) that detects smells. It is known to be about 100 times the size of a human’s, which contributes to the bear’s super sense of smell.

While in the snout, odors are captured by the millions of nerves, and the messages are relayed to the base of the brain. This is where the olfactory bulb, which is about 5 times the size of ours interprets the sensory data that it just received.

What does this mean for the bear? Food smell – good! Pepper spray – bad.

What Affects The Bear’s Super Smeller?

Many factors affect how well a bear smells and whether you become food or not. The leading factors include wind, humidity, and temperature.

black bear cub smelling and sniffing it out
black bear cub sniffing it out

How Wind Affects A Bear Smells:

Have you ever heard the saying, “keep the wind at your back” this could save your life? Well, maybe. What I mean is smell floats in the air. When the wind is facing you your smell drifts backward and allows a bear to track you.

When the wind is ‘at your back’ your odor floats forward. This is a more ideal case in the wilderness because you can see up ahead and make plans, and the bear gets warned before your arrival.

As a side note, be aware that on a windy day in the wild, your sound gets muffled. So, it is wise to be on the lookout for bear as they may not hear you coming.

How Humidity Affects A Bear’s Smell:

Humidity is the measure of water vapor in the air. High humidity means lots of water vapor and low humidity is…you get the point. Think of water vapor in the air like a smell transport system. Our odors attach to water vapor in the air and float away from us in the wind.

You can see how the higher humidity, the greater the chance of a bear smelling us from miles away.

How Temperature Affects A Bear’s Smell:

If a windy and humid day carries odors to the bear miles away, what does temperature have to do with it?

For example, if you live in the Northeast U.S. you know that colder temperatures carry less humidity while the summer months can be dreadfully humid. These warmer months with high humidity carry more odorous water vapor away from us and toward the bear.

21 Ridiculously Easy Ways To Attract Bears To Your Tent!

This list could be a mile long however, hopefully, most of them won’t be in your backpack or tent. Here is a comprehensive list of most items that bears are attracted to when you are out on the trail or in your tent.

This doesn’t mean that they want to eat everything that you have in camp. Sometimes, they are just curious and want to have a sniff. For example, campers have it in their heads that mothballs (on the list below) deter bears. However, I have read that it actually makes a bear curious. Like, hmm a new smell, let’s go check it out.

21 ridiculously easy ways to attract bears into your tent:

  1. All Human Foods
  2. Deodorants
  3. Soaps
  4. Shampoos
  5. Cosmetics
  6. Perfumes
  7. Insect Repellent
  8. Tea Bags
  9. Pet Food
  10. Skin Lotion
  11. Suntan Lotion
  12. Toothpaste
  13. Candles
  14. Mothballs
  15. Cooking: Utensils
  16. Cookware: Pots
  17. Cooking Oils
  18. Stove/ Lantern Fuel
  19. Unopened Cans
  20. Urine and Feces
  21. Coffee Grounds

How about printing out the table below, laminating it and keeping it in your pack for help packing for your next adventure.

21 bear attractants in a table format
Print this out, laminate it and bring on your next trip!

What Deters Bears From You And Your Tent?

There are many ways to deter a bear from entering your campsite and even into your tent. If a bear is not deterred easily it is maybe because he has gotten used to being around humans. Especially, when we can be so messy at times.

When you are out in the wilderness, it is essential to be on your best ‘cleaning’ behavior. I am a bit OCD when it comes to keeping my house clean (yes, I am a guy), so, the same should hold when you are out and about on a backpacking trip.

However, I know how tired and hungry one gets from hiking all day. Phew! So, it is best to make a plan, even if it is in your head. Once camp is set up, implement that plan. Keep all the smelly items up and out of the way from a bear. Clean your cookware and eating ware (is that a word?) immediately after you eat then pack it away from the tent.

9 Common Bear Deterrents

  1. Air Horn
  2. Pepper Spray
  3. Bells and Chatter
  4. Cider Vinegar
  5. Lysol
  6. Bear Canister
  7. Pinesol
  8. Ammonia
  9. Common Sense

Print out this chart to help you plan your next trip.

9 bear deterrents in table form
Have a plan to execute if necessary!

How Does Bear Repellent Work?

Bear sprays use capsaicin as the chemical irritant keeping you safe from a bear attack. This chemical irritant, found naturally in chili peppers is an irritant to the nose, mouth, eyes, throat, and lungs.

However, bear sprays use it at a very concentrated level of between 1 and 2 percent in each bottle. Because of the concentration, it is not used on clothing or your backpack.

Most bear sprays discharge up to 30 feet at a time. It is advised to get a minimum dose of 8 ounces. Bear sprays are only used when a bear is charging or attacking.

5 Best Bear Deterrent Products On The Market

After performing a quick review on Amazon, I am including this list of bear deterrents. To let you know, I have not used these products so cannot personally vouch for their effectiveness. They all have 4+ or better ratings.

bear deterrent spray as an example
Bear Deterrent Example
  • SABRE Frontiersman Bear Spray with Holster: Amazon Link
  • Guard Alaska Bear Spray with Nylon Holster: Amazon Link
  • Udap 2 Personal Defense Bear Sprays w/Holsters 12VHP: Amazon Link
  • Mace Brand Self Defense Magnum Collection: Amazon Link
  • Counter Assault 8.1 Ounce Bear Deterrent Spray w/ Holster: Amazon Link

How To Keep Your Camping Area Safe From Bears

This takes a little bit of common sense and understanding of the camping situation. You and your friends are in bear territory. It is like you showing up at my house for a party. Because you don’t own my house, you respect it (hopefully, or you really aren’t my friend) and don’t mess it up.

The same holds for bears. When camping clean up after yourself, don’t place trash or food into the fire, and don’t under any circumstances eat or keep smelly items (refer back to ‘attractants’ above) in your tent.

Here is a cute video from the New Hampshire State Parks, Prepare for Bear: Tips for Camping Safely.

NH State Parks Video: Prepare for Bear: Tips for Camping Safely

Bear Canisters Keep You And Bear Safe

If you are car camping this wouldn’t make sense. However, as a backpacker, there are a number of State and National Parks where you cannot camp without a Bear Canister.

So, what is the purpose of the canister? A bear canister protects your food from bears. It does this by being relatively heavy and ‘smell-proof’.

A canister ranges between 2 and 4 pounds, has a carrying capacity of about a week’s worth of food, and is made with hard-sided dense plastics.

Certain bear dense areas require the use of bear canisters. These include many of our National and State Parks. If you intend on travelling to one of these parks, I urge you to find out the requirements ahead of time.

It is hard to determine what is the best bear canister to choose. That is why I have compiled a quick reference to some reputable bear canisters on the market as of this writing. Expect to pay between $60 and $100 for most canisters. You can check out Bear Canisters here on Amazon.

Top hard shell bear canisters in table form
Top hard shell bear canisters

The Top 9 Bear Safety Tactics:

Protecting yourself when at camp or in your tent is all about eliminating attractants. So, let’s review:

  1. Keep everything in a bear-resistant canister. This eliminates the smell of all the objects that we listed in the ‘attractants’ table.
  2. Become obsessed with cleaning your area after eating or using any lotions, sprays, shampoos, or soaps.
  3. Never put anything on the ‘attractant’ list in your tent. Especially that late-night snack!
  4. Follow the rules of the park. If you are backpacking at a National or State Park, obey their rules. Many require the use of a bear canister.
  5. Don’t sleep in the clothes that you ate in. This may seem odd but smells stick to clothing, changing will keep you safer in your tent.
  6. When in the backcountry, triangulate. Meaning, make a triangle with food/cooking area, tent, and canister storage. Make that each area is at least 100 feet apart.
  7. Get in the practice of packing out what you take into the wilderness. All trash should be packed in your bear canister.
  8. Keep your bear spray in your tent and easily accessible.
  9. Make sure that your pets are on a leash so they don’t wander off at night. Pets make a great warning system, well maybe not cats.

Do This When You Encounter A Bear On The Trail!

This video is from the National Park Service. The ranger explains what to do when encountering a bear in the wild. Have a look.

National Park Bear Safety Video