Bears…. we love ‘em and we hate ‘em. We’re fascinated with them, and we fear them. They are like us, in as many ways, as they are different from us. While man is closer anatomically to being a frugivore, who continues physically evolving into an omnivore, we are also a creature who spread around the world by changing our eating habits from fruits, vegetation and seeds, to the more efficient role of the meat eater. Black bears and grizzlies, on the other hand, are creatures who are anatomically closer to being carnivores, but who successfully pursued an omnivorous diet, and learned to exploit many different sources of food in many different habitats.

Our nightmare vision of the grizzly prowling just outside the dissolving glow of the camp fire’s light, or the fear that we’ll lose our vegetable garden or livestock or trash barrels to a marauding black bear, is balanced by the almost comical and brilliant attempts of the black bear to figure out how to break into our stored food and trash, or the manner in which bears routinely entertain themselves and each other with the natural toys and circumstances nature provides.

Where did they come from, and when?

The ancestors of modern North American bears evolved in Asia during the Pleistocene, wandering over to Alaska during several appearances of the Bering land bridge, between the Bering and Kamchatka Peninsulas. Advancing and receding glaciers, fueled by evaporating sea water, caused ocean levels to alternately drop and rise, exposing and resubmerging the Bering Strait.  The ancestors of black bears came across half a million years ago, and it is suspected that black bears adapted to climbing trees to escape the larger, faster and more strictly carnivorous short-faced bear, which, fortunately for us, joined the extinction parade about  5,000 years ago. The glacially isolated polar bears split off from grizzlies in Asia about 130,000 years ago, and followed grizzlies across the land bridge about 100,000 years ago. Grizzlies stayed bottled up in Alaska for a while, possibly thanks to the presence of the same short-faced bear in the areas that became Canada and the U.S.

These factors set the pattern for survival for each species: black bears tend to retreat, often up trees, while the heavier, stockier grizzly, evolving in the more open tundra and taiga, areas with fewer and smaller trees, developed the best-defense-is-a-great-offense approach to survival.

There are about 500,000 black bears in North America, probably 7,000 across their currently expanding range in New York State, with more than half of these within the Adirondack Region. Black bears are the only bear found uniquely in North America, and they tend to live where there is forest and vegetation for cover, and swamp, as in the east, or in the mountain areas out west. As with a slew of other mammals, bears have learned that while human beings mean hunting, in many areas, they also mean food and sustenance, particularly when the bear’s natural sources of food fail, as when drought wiped out the berry crop in the Summer of 2012, driving so many bears into camp sites and back yards.

There are about 60,000 grizzly bears in North America, sweeping across Alaska, the Yukon and the Northwest Territories, spilling down the extensions of the Rocky Mountains, through Alberta, Saskatchewan and British Columbia, through Montana and Idaho into Yellowstone, with a diminishing presence on the surrounding prairies. The principal difference between inland grizzlies and the Alaskan coastal brown bears are the rich salmon diet of the latter.

Why you should never feed a bear

Bears are opportunistic, omnivorous feeders, creatures of habit, who will continually revisit areas where they have found food in the past, whether those food sources are natural, or provided by human activities. With regard to the latter, this is why it is almost always a mistake to feed a bear: if you’re camping out in the High Peaks, and you purposely or inadvertently provide food for a foraging black bear, you pretty much guarantee that the next camper will have to deal with that bear’s expectation that humans mean food. Similarly, because we experience bears as large and intelligent mammals, sometimes frightening and sometimes entertaining, we have a natural tendency to sympathize with their plights, particularly in the case of orphaned cubs and yearlings.

Mature bears are unique among the larger North American mammals in that hunting is the number one cause of mortality. As with most other wildlife at any age, starvation is the main cause of mortality among cubs and yearling bears. At the same time, bears, like deer, have discovered that suburban America is not only a great place to forage for food, but relatively safe from hunting, as local laws tend to forbid firearm discharge in developed neighborhoods.

Black Bears

Black Bear boars range from 150 lbs. to 550 lbs, with 300 lbs. being about average, while sows range from 90 to 300 lbs, with about 170 being the average. Black bears live to about 15 years in the wild, and sometimes twice that in captivity, when their number one challenge in life, food, is removed as an issue. Black bears walk pigeon-toed, but can run up to 30 mph. Physically, they’re characterized by shoulders large and powerful, though lacking the thick knot of muscles grizzlies have between their shoulders, and a straight facial profile which is often described as “roman”, as opposed to the grizzly’s more dish-shaped profile. In addition the black bear’s dark claws are shorter and more curved, adapted to climbing, while the grizzly’s claws are longer, less curved, lighter shaded and adapted for digging out rodents and plant tubers. A black bear’s paws are considerably more dexterous in manipulating objects than their appearance would suggest, and their ears are larger and more clearly defined than those of the grizzly. Black bears mark their presence by biting and clawing trees, rubbing their backs up and down on tree trunks, and by a peculiar stiff-kneed weight pressuring of their front paws into the ground, leaving nearly perfect prints.

Bears have extremely sensitive noses, better hearing than people possess, and black bears apparently have sufficient color vision acuity, that, according to Jeff Fair, in “The Great American Bear”, they can recognize rangers in the Smokies by uniform and by car. Black bears, like grizzlies, come in various shades, from the predominant black of the eastern black bear, and occasional cinnamon in the Midwest, to sometimes brownish out west in grizzly country, a convenient evolutionary adaptation to resemble their more imposing grizzly cousin, to the blondish and whitish bears of British Columbia, the famous spirit, or ghost bear, the Kermode bear.

Territory

Bears are not as strictly territorial as wolves are, and their territories vary by gender, availability of food, time of year, and the presence of tolerant neighbors. Females are more territorial than are males, and sows’ territories are often bordered by the smaller territories of their dispersed daughters. Dispersal is what takes place when yearling cubs are booted out of their mother’s territory by an eager-to-mate-again Mom, sometime in June after some of her cubs may have spent their second Winter with her. Bear “family life” is essentially about mom and cubs. Once a young male has been booted from Mom’s territory, or dispersed on his own before that second Winter, his only future interaction with sows will be during mating season. Territory defense has more to do with protecting food sources against other bears than, say, the danger to cubs of wandering male bears (a danger more characteristic of grizzly bears), so allowing your daughters to stake out adjacent territories gives Mom an effective buffer zone against general food poaching by strangers. Average female territories in New Hampshire and Maine are about ten square miles, while males may cover anywhere from 15 to 70 square miles. Male yearlings are more apt to wander around in search of their own territory, but territories are commonly violated by the presence of short-term seasonally available food in any given area.

Through the Seasons – Pre Hibernation

Bear activity is driven by the seasons, particularly with respect to food availability, mating and giving birth.  The bear’s specific form of hibernation is what really distinguishes bears from other mammals, so we’ll start with the bear’s activities during late Summer and Autumn. Since bears don’t eat while hibernating, they go through a period of “hyperphagia”, or overeating, in Fall, gradually increasing their consumption until they spend about 20 hours a day eating, consuming, for example, American mountain ash berries, black cherries, mountain holly fruits and hazelnuts, gradually switching to wild apples and raisins, arrowwood, and finally that “hard mast”, beechnuts and acorns in late September and October. Out west the hard mast consists of whitebark pine nuts.  A larger than average hard mast harvest will result in fatter bears, which in turn will result in more cubs born to pregnant sows during hibernation. If the following year features droughts, this will result in thinner food yields, and too many cubs trying to feed themselves on too few berries, acorns, etc., as Nature adjusts the balance of supply and demand. You may have spotted a “bear’s nest” in a beech or oak tree, where a black bear has climbed out on a limb, reaching out and pulling in to him the nut laden branches. Prior to hibernation, it is literally true that a fat bear is a healthy bear, and they’ll go from consuming 5 to 8 kilocalories a day, to up to 20.

A bear is ready to hibernate when a trigger-like physiological mechanism causes the bear to gradually stop eating and drinking, as their body begins to metabolize the fat they’ve been building up. They walk around in a kind of pre-hibernation daze, looking for a location to den up. For pregnant sows, this may begin in late September, followed by sows with first year cubs born the previous January, and finally barren sows. Boars may not begin hibernation till late October or November.  Curiously, it has been reported that many boar grizzlies in Yellowstone have stopped hibernating, because wolves are apparently such good providers of left-overs, stealable prey carcasses, and carcasses inadequately guarded by “meat drunk” pack members, that the bears are able to access enough protein to avoid hibernation altogether. This is a risky approach, however, as successful denning is based on metabolizing fat, not protein, so the grizzly may find himself in trouble if midway through Winter, his carrion food supply is seriously diminished.

Denning and Hibernation

Dens may be caves, hollows in trees, an excavated hollow under a fallen tree’s root base, under the porch or foundation of a seasonal cabin, and for some boars, just a clearing with sufficient wind break surrounding it, and a snowy blanket to augment the bear’s winter coat and keep the bear warm. Pregnant sows, and mothers who sometimes have yearling cubs with them, naturally seek those dens with more security. Bears may gather and line the dens with fallen leaves, pine boughs, and other materials to make for a more comfortable and well insulated bed.

Hibernation may be defined as the seasonal reduction of metabolism, concurrent with reduction in food availability and temperature. In short, just as birds of prey migrate not because of the cold, but because the hibernation of many prey animals deprives them of a survival-enabling quantity of potential prey, so the main reason bears hibernate is as an efficient response to the hardships of feeding oneself during Winter.

Bears are sometimes described as not true hibernators. This is because while their heart rate may slow down from 50 beats per minute to about ten during hibernation, their body temperature only drops about 12 degrees, whereas the body temperature of most hibernating mammals may drop to a few degrees above freezing. On the other hand, while bears may indeed rouse, and walk around during balmier winter days, they can go through their entire hibernation without having to urinate, defecate or ingest food, while the “true” hibernators have to do all these things from time to time, during hibernation.

The reason for this is that bears spend their hibernation burning the fat they ingested during hyperphagia, shedding 25 to 40% of their body mass, but not lean body mass, such as muscle tissue, bone and protein. I can picture the late night TV ads already: “SHED WEIGHT WHILE HIBERNATING…. er… SLEEPING!” All kidding aside, medical research is very interested in understanding bear hibernation because of the many possible human medical applications, which include gallstone treatment, kidney disease,  muscle cramping, bone calcium loss, renal disease, anorexia, skin regeneration and suspended animation. Imagine future astronauts traveling to distant planets while in a state of hibernation.

Metabolizing fat produces more energy and water, but less urine, which ends up being recycled anyway. Urea in the blood is converted into CO2, water and ammonia. During a process termed “nitrogen shuttle”, ammonia and glycerol produce amino acids and protein. Three grams of urea nitrogen becomes 21 grams of protein, enough to develop one cub. The period of hibernation is a function of latitude and climate, such that while a Florida black bear may hibernate for only two months, one in the Yukon may do so for up to seven months.

Winter and the Birth of Cubs

What all this process means, in effect, is that hibernating sows give birth during a period of virtual starvation. Bears mate in late June or early July, and sows are promiscuous by nature, sometimes mating with a number of boars, such that cubs of the same litter may have different fathers. Sows experience delayed implantation of blastocysts, becoming pregnant only after they have successfully prepared themselves for hibernation through hyperphagia.  The blastocysts of a starving sow will dissolve, thus preventing the added stress of giving birth to an inadequately prepared sow.

While litters of two cubs are typical, in areas of abundant food, sows may produce up to six cubs, each weighing about  12 ounces. Mama’s milk, delivered through six nipples, is 25 to 30% fat, low in carbohydrates, and high in ash, calcium and phosphorous. Orphaned and abandoned cubs may be successfully placed with nursing sows at this age. The cubs grow quickly, even as Mom continues to shed body fat, and will be about ten pounds by April.

Spring Fever

When Mom leads her cubs out of the den in Spring, she continues in a state of biochemical narcosis, that is, still metabolizing fat, while losing weight, and nursing her cubs, who are growing rapidly. After a week or so, mom starts foraging, finding squirrel caches left over from Winter, eating grasses, skunk cabbage and fiddleheads, teaching her cubs what to eat and where to find it. Catkins, roots, corms, early fruits and leaves, vegetation low in woody cellulose, round out the Spring diet. Carrion, the bodies of animals killed by Winter, as well as any deer fawns or moose calves the bears come across while foraging, bring much needed protein, as do ants, ant pupae, yellow jackets and bees, which appear on the menu in June.

Summer Romance

Summer brings mating season and the soft mast of berries. Sows which still have yearling cubs with them, are anxious to mate again, and begin rejecting their cubs. At this point, the cubs have spent more than a year learning the ropes from Mom, and are ready to take care of themselves, a condition Mom encourages by displays of impatience, charging her cubs when they try to follow her, and making it clear she wants her shadowing offspring to leave her alone. Siblings may eventually wander off together, and learn while foraging together that companionship is great, except when a shared limited food source means not having enough to eat, which may lead to the siblings striking out on their own, with females trying to establish territories adjacent to Mom’s, while males look for territories not dominated by larger males.

Males detect females going into estrus in late June and early July, and may begin tailing prospective females, waiting for signs of receptivity. The boars may forage and feed alongside their prospective sow, waiting for her to signal readiness, also fending off approaches by other males, who may test their resolve with respect to a particular sow. Much of this effort may be wasted, as sows are promiscuous, and may end up mating with more than one male anyway, with the interesting result that litters may have multiple fathers. Copulation may last up to 30 minutes.

 Meanwhile the berry crops start bearing fruit, pin cherries, sarsaparilla berries and blueberries in July, and red raspberries, choke cherries, blackberries and dogwood fruits in August. In good years there may be plenty of soft mast for everyone. Just as Alaskan brown bears flock to salmon streams, and tolerate the presence of other bears, and even human fisherman, thanks to the numbers of migrating and spawning salmon, so a rich crop of soft mast may find black bears eating these berries exclusively for many days, often within sight of one another.

Keeping Bears away from Homes and Camp Sites

How do you keep bears out of your camp site? In the case of camping in the High Peaks of the Adirondacks, they’ve made it academic: you must have with you an approved bear canister for food storage. More generally, never cook or store food anywhere near where you plan to lay out your sleeping bag. If you’re staying in a lean-to or tent next to a campfire, don’t cook over the campfire, as the odor of dripping fat and grease will be just as attractive to the bears, as actual food will be. For the same reason, heat food over your portable camp stoves far from the sleeping area. Before the canister law, folks in the high peaks would typically store all food, as well as implements for eating and cooking in  a bag, which would be hung from a branch high enough, and far away enough from the tree trunk, and far from the sleeping area. Better to watch the bears at a distance, figuring out how to reach your suspended food cache, than to have them in camp with you. If black bears are attracted to your campsite anyway, bang pots together, clap hands, yell at them, shine lights at them, in short, make their fear of your noisy dissuasion overcome their attraction to the odors of food.

How do you keep bears out of your garbage and garden at home? For the former, use approved bear-proof garbage containers, like the ones pictured. Only place your pet food bowls outside while your pets are actually eating, and only hang your bird and suet feeders during winter, when the bears are hibernating. You shouldn’t be feeding birds during the other three seasons anyway, as they have to learn to forage and store food, if they’re going to survive during periods when you’re not feeding them. Keep the compost pile far from the house, as it will absolutely attract bears, or locate it next to the vegetable garden, and use a solar electric fence to surround the garden, compost and any bee hives you keep on your property.

Are Bears dangerous to people?

I once heard George Carlin open a set by saying that “you never hear about a bear until he bites someone”, and the audience laughed like that was the funniest thing they had ever heard, when in fact, it was an accurate description of how our media works. This isn’t about any particular political point of view. It’s simply a reminder that all forms of media face the challenge of attracting and retaining readers, viewers, whoever, and they often do so by taking the exceptional and wildly improbable, and presenting it as the state of expectations.  

Let’s face it, we want to be frightened.  We want to say, “that could have been me”, or to paraphrase Carlin, nobody wants to read a story that tells us 50 million people landed or took off safely in jets from Kennedy airport last year (which is accurate). They just want to read about the jet that crashed, or in general, about human misfortune. Think “Bart the Bear”, and any of his movies, or “The Grey”, that ridiculous movie about clunky-looking wolves attacking plane crash survivors, in which even the story line makes zero sense, and is merely employed to set up the carnage that follows.

There are about one to three attacks by grizzly bears on people in North America in any given year, with the average over the last century being two. Most attacks are related to surprising a grizzly, either a sow protecting her cubs, or a bear protecting the carcass of an animal that it is consuming. While the very thought of an attack by a bear is quite terrifying, the logical question should be, how many people see bears up close in any given year?

This is a very large number. Using just Yellowstone National Park, the only Park for which I could locate stats, in 2008 alone, over 1,000 people reported seeing grizzlies, which likely means that five times that many saw grizzlies and didn’t report the sighting to any authorities, like rangers, etc. Over the last 25 years, I’ve seen many grizzlies, some in National Parks like Denali or Banff, some at private camps like Knights Inlet on the B.C. coast, and many of them fairly up close, where one of the bear’s options was to whack me, including the one in Denali last May, whose photograph appears above.  When it comes to black bears, millions of people see black bears each year, and yet, there is a fatal encounter about once every four years. In fact, your chances of being killed by lightening or a spider bite, or an attack by a dog, are very much higher, even in bear country. When it comes to bear encounters, think statistics, not scary anecdotes, which play into our deepest fears, and if you’re truly interested in bear attacks as a social phenomenon, read the Stephen Herrero book, “Bear Attacks, Their Causes and Avoidance”. I know of no physical attacks by black bears on people in the Adirondacks, and many of us have seen bears up close.

So… what should you do when you see a bear? Well, for starters, get your camera ready. Never run, as the slowest bear in history, is faster than Michael Johnson, or whoever holds the current Olympic sprinting records. Contrary to Hollywood movies, when a bear stands up to look at you, they’re first trying to figure out what you are, so they get one of nature’s  most sensitive noses higher in the air, so as to identify you. Grizzlies are obviously more to be concerned about than black bears, so if a grizzly stands and looks at you, but doesn’t get down and leave, this may mean he can’t figure out what you are. If you’re wearing a hat, gently waft it in the bear’s direction, so that he can smell that you are a human being. If a black bear feels threatened, it may initiate a series of bluff charges, which will almost certainly end in the bear veering off. Chomping or clacking the jaws is generally also a bluff, but with grizzlies, may very rarely be followed by a charge ending in contact.

Many folks carry firearms in bear country, but in the rare case of a grizzly attack, some people have been killed by the bear they just shot. I prefer carrying pepper spray in grizzly country, because a face full of pepper spray, literally turns you into super skunk in the bears eyes. The key with pepper spray is to wear it on your belt, and obviously have it in your hand, ready to use, the second it becomes clear that the bear may choose contact. Wearing “bear bells” on your pack in grizzly country, may lessen the danger of surprising a grizzly at close quarters, as they will hear you coming, and likely flee the scene.

Steve Hall