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Who is the "King" of the bears?
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Also, let's not forget about a long-forgotten brown bear subspecies, the Atlas Bear.
It was one of the lower-sized brown bear subspecies, so it obviously brings the brown bear lower at section I. Not much is known about its predation habits. I'd like to say that it was much more herbivorous than omnivorous due to more influential and hyper-carniovorous competitors around the area, including Atlas Lions. This brings the brown bear's points in section II slightly lower. Again, due to severe carnivore competition and lower ranking within the dominance of its domain, the Atlas Bear brings the brown bear down. For brown bears, subspecies will also be taken into account (using a "points" system), and the total point average of the brown bear subspecies will be calculated for each category. All other bears are assumed separate species, and will have a "points" system accounted for them as well. +1 point = any positive trait for any of the three categories -1 point = any negative trait for any of the three categories 
I have to wonder about the Atlas bear. We know so little. Our profile of the Atlas bear comes from a study made by an English military officer named Crowther in 1840. The Atlas bear is believed to have become extinct during the 1870s. Massive hunting and capturing of this bear took place over the centuries. The Romans used them in their blood sports. Sport hunters finished them off. Remember than it was a similar situation that reduced the European brown bear from a huge ferocious bear into a smaller and much less carnivorous bear. Therefore, we cannot be so certain of Crowther's description.
From a site given by Guate Gojira on post #24 - http://www.adfg.alaska.gov/index.cfm?adfg=wildlifenews.view_article&articles_id=232
The Biggest Bear ... Ever By Nancy Sisinyak You are watching a pride of lions gorging on the still-warm carcass of a young elephant. Wild horses graze nearby, wide ears active, great marble eyes rolling nervously toward the preoccupied cats. Suddenly the lead stallion raises his head and snorts in alarm. His harem of mares dance in sudden agitation, staring off in the distance. Slowly climbing over the horizon, a looming form approaches at a steady pace. As one, with the synchrony of a wheeling flock of birds, the herd bolts. The lions grumble deep in their throats and rise to stand at point. The animal is closer now. Close enough for you to realize that it is the largest bear you have ever seen. You crouch frozen, adrenaline coursing through you like a rushing river. You are transfixed by the size of this beast. As the bear passes, its odor fills your nostrils, the rotten-flesh stench of a carnivore. The lions, heads low, a steady growl of warning rumbling from within, turn to block the carcass, to face off against their nemesis… Just another tale of survival in the Alaska wilderness. But wait. Lions, wild horses, and elephants in Alaska? You bet. During the Pleistocene epoch (from 1.8 million to 10,000 years ago) all of these creatures roamed the grassy steppes that would later become the boreal forests of Interior Alaska. In fact, the confrontation between the pride of steppe lions and the short-faced bear (Arctodus simus) over that mammoth carcass could have easily taken place where the University of Alaska Fairbanks campus sits today. This is strangely appropriate, since several mysteries surrounding this bear were solved within a bone-filled, dusty lab of UAF less than a decade ago. Paul Matheus, then Director of the Alaska Quaternary Center, challenged some long accepted beliefs about the life history of this mega bear. Thanks to his research, we now may know what Arctodus ate, how it procured its food and even the most plausible explanation for its sudden disappearance a scant 12,000 years ago. The short-faced bear first loped into paleontological prominence in 1967, when Dr. Bjorn Kurten of the University of Helsinki authored a paper entitled, Pleistocene Bears of North America. Kurten wrote that Arctodus was “…by far the most powerful predator in the Pleistocene fauna of North America.” Though Dr. Matheus is quick to express his deep respect for Kurten’s work, to the point of reverently referring to the world renowned Finnish paleontologist as the “bear god,” he does not agree with Kurten’s conclusion that the bear was a formidable predator. Quarternary biologists, who study the life forms of the Pleistocene, encounter a range of obstacles when trying to determine what ecological niche an extinct animal may have occupied. They can’t climb a hill and make observations through a spotting scope. They have to rely on evidence left behind, mainly bones. The bones that individual short-faced bears left behind tell us that this bear ate meat. The skull has a shortened snout and powerfully built jaws that could crush bone. Matheus says that Arctodus’ canine teeth were well suited for puncturing tough hide, and its large, jagged molars were ideal for gnawing, tearing, and slicing meat. These physical attributes, alone, however, are not sufficient to prove that the short-faced bear was a true carnivore and not an omnivore, as are today’s modern grizzlies and black bears. Matheus used a technique called “stable isotope analysis” to quell any doubts about Arctodus’ diet. Simply put, nitrogen occurs in nature in two forms, nitrogen-15 (15N) and nitrogen-14 (14N). The ratio of 15N to 14N in a bone sample can tell researchers whether an animal was a carnivore, an herbivore, or an omnivore. Matheus found a very high 15N to 14N ratio in all the Arctodus bone samples he tested. This nitrogen “signature” is indicative of a true carnivore. Thus, the stable isotope analysis when coupled with the physical characteristics of fossil skulls and teeth leaves little room for argument: The short-faced bear ate only meat. “Arctodus weighed about 1,600 pounds to 1,900 pounds,” says Matheus. That’s roughly twice the weight of the average modern Alaska coastal brown bear. “On hind legs, it stood 8 feet to 10 feet tall.” Even on all fours, Arctodus could look a 6-foot man in the eye. It’s tempting to assume that, since this bear was such an outsized carnivore, it was the alpha predator of its time. It isn’t difficult to imagine Arctodus pulling down woolly mammoths or steppe bison, or crushing the spine of a Pleistocene moose with one swipe of a sledgehammer paw. But, the ancient bones that Matheus studied, whispered a different story. “There are two lines of thinking about Arctodus as a predator,” Matheus explains. “The first I call ‘The Linebacker Hypothesis.’ It envisions a mighty brute that overwhelmed the largest mammals of the Pleistocene. The bear supposedly used its massive body to tackle things like mammoths and giant ground sloths. The problem with this idea is that Arctodus, though very large, was very gracile (light-boned). In order to bring down these magafauna (large animals), Arctodus would have to have been a more robust creature sporting thicker, stronger bones.” Matheus calls the second theory, “The Cheetah Hypothesis.” Some believe the long-legged Arctodus was able to run down smaller, fleet-footed Pleistocene herbivores such as steppe horses and saiga antelopes. In this scenario however, the short-faced bear’s sheer physical mass would be a handicap. “Size works against you in developing speed,” notes Matheus. “Once an animal tops 320 pounds to 400 pounds, additional weight sacrifices speed. Furthermore, Arctodus’ skeletal structure does not articulate in a way that would have allowed it to make quick turns, an ability required of any predator that survives by killing agile prey.” After studying the skeletal record, Matheus determined that Arctodus was a pacer. That is, both of its right legs moved forward together, then both left legs moved forward in unison. This is the primary means of locomotion for elephants and camels. Pacing isn’t particularly fast, but it is very energy-efficient. An animal that is built for pacing is designed for endurance rather than speed. So where does this leave Arctodus in the grand Pleistocene scheme? This monster ate only meat, yet it seems to have been ill equipped physically as a hunter. Matheus believes the answer is clear, and reflects some recent theories concerning another prehistoric monster, Tyrannosaurus: “Arcotdus,” he claims, was a scavenger.” The largest bear to have ever paced the earth depended upon other predators to make the kills it needed to survive. “Arctodus located carrion by rising up on its hind feet and sniffing the air,” Matheus surmises. “Standing is something to which its skeleton was well suited.” The tall bear’s upright posture would have placed its wide nose high in the air, allowing it to detect even far off food sources. Arctodus could then drop down on its lanky legs and pace steadily, tirelessly, to even distant kills. Once there, the bear probably used its size to intimidate lesser carnivores and drive them away from their prey. The short–faced bear was, in this way well-suited for survival in Pleistocene Alaska, but its fate may have been inextricably linked to the climate of that age. The warming temperatures that caused the great glaciers sheeting much of the North American continent at the time to recede also gradually transformed the arid, grassy steppes of Interior Alaska into the boreal forests of today. The steppe horse, woolly mammoth and saiga antelope, as well as the predators that brought them down were grassland creatures and thus slowly disappeared as the forest took over their grassland habitat. The great bear could not scavenge enough food to support its mighty bulk. Unlike its cousins, the cave bear, grizzly, and black bear, Arctodus could not supplement its diet with fruits and vegetation. In the end, Alaska’s mightiest carnivore was essentially done in by trees. The same trees that so altered the grassland habitat that prey animals and their predators went extinct, left nothing for the great bear to scavenge. The bear stands on its hind legs, emphasizing its size. It is the tallest thing on the steppe. Your knees quiver, you try to quiet your breath, your heart. The lions crouch, tail-tips wriggling. Suddenly the monster slams its weight down on lanky front legs and charges the waiting defenders. The dominant lion dodges and tries a lunge from the side, but the bear swings one massive paw and the cat is gone, tumbling and bouncing like a rock chucked across the grass. The remaining felines snarl, lips drawing black lines above razor teeth, haunches trembling in indecision. Injured, the downed cat struggles to its feet, hobbles off dragging a hind leg, and the rest of the pride breaks from the kill to follow. Arctodus moves in on the mammoth carcass. As you slink away, stepping carefully, the sound of cracking bones hurries you across the steppe. You head for home, too shaken to resume hunting now. There will be time to try again tomorrow, for this new land you entered a season ago abounds with game. The grasses are green and lush. And between the waving blades, a new growth is emerging. Its woody stems support spade-like leaves that quake hypnotically in the breeze. You pause to wonder at them, then lay down your spear and allow the heavy bison hide to slide off your shoulders. After all, it is an unusually warm day. For more information about the short-faced bear and other amazing Pleistocene animals, visit www.beringia.com. Nancy Sisinyak is an information officer with the the Alaska Department of Fish and Game, Division of Sport Fish, and lives in Fairbanks.
Another from post #24 - https://www.bear.org/website/bear-pages/extinct-short-faced-bear/195-how-big-was-this-short-faced-bear.html
Extinct Short-faced Bear EmailPrint How big was this Short-faced Bear? He could reach up 14½ to 15 feet. He could reach 2 ½ to 3 feet higher with a paw than he could reach with his mouth. This skeleton measures 72 inches from the center of the shoulder blade to the tips of the toes (adding 2 inches for the missing claws). Subtracting 42 inches from the center of the shoulder blade to the tip of the nose, this bear could reach 30 inches above his up-stretched nose—to at least 14½ feet. If he rotated his shoulder upward a few inches, he could reach even higher. Ice Age campers had to hang their food higher than campers do today. He weighed about a ton. Archeologists estimate most giant short-faced bears, including females, to weigh 1600 to 1900 pounds. Some estimates exceed a ton. This large male specimen probably weighed close to a ton, which is more than twice what the Bear Center's resident adult male Ted weighs.
2 very different bears coexisted in North America during the late Pleistocene. The short-faced bear was without argument the dominant bear and likely the dominant predator of his environment. But, the grizzly was a fighter. The giant wolves, the giant jaguar, the scimitar cats, the saber-toothed cats, and the big cat known as the American lion knew this. The American black bear is a rather timid bear probably because during the Pleistocene he was forever scurrying up a tree. The grizzly, on the otherhand, like a kid growing up in a tough neighborhood, had to be a fighter. This is why Lewis and Clark discovered that the grizzly was a much more dangerous adversary than the bears they had known back east.
 *This image is copyright of its original author  *This image is copyright of its original author
In category 3, competition with other predators, the polar bear has been dealt an unfavorable hand. First of all, the polar bear is in fact the greatest of living bears in that he is the biggest and certainly the most carnivorous. As for being a survivor, all credit due him is shared by his ancestral grizzly grandparents. No other carnivore ( forget herbivores ) conquered the harshest of all earthly environments; the pure arctic. No wild dogs, no wild cats, no mustelids. As for our living bears, the polar bear is almost a shoe-in. But, his predator competition, those other predators who feed on seals and walrus, live in the sea. We must also remember that the arctic ocean is as much a part of the polar bear's environment as is the solid ice. Among the Greenland sharks and the Orcas, the polar bear is not the dominant predator.
It would, however, not hurt my feelings one iota if the polar bear was to somehow win this contest. If someone was to create a family tree of Ursus arctos, the tree would be incomplete without the polar bear. 
I premise that i don't know in depht the various species of bear, particulary the extinct bears.
I think that in terms of attitude the Polar Bear can quietly compete with the other species of his genus and emerge dominant, even if is a highly specialized bear, and is a very good hunter in the extreme conditions of his environment. My vote is for the Polar Bear. (10-31-2016, 05:09 AM)GuateGojira Wrote: Hello guys. Great topic!!! Over on the prehistoric animals section, on the topic 'Bears of the Pleistocene', I would love to learn something about Arctotherium bonariense. (10-26-2016, 08:46 PM)Polar Wrote:(10-26-2016, 07:32 PM)Pckts Wrote: In regards to the "prey category" I'd have to say the polar bear. Even if we were to compare prey of each species of bear, non solely survive off meat/blubber like the polar. This forces polar bears to tangle with prey much more often, add that to the fact that they must search endlessly through the harshest terrain imaginable to find the prey. They can't afford to be choosy and that probably means taking much more risk. I also read from some long ago forgotten source that the 'Tyrant Sea Bear' was a hunter of woolly mammoths. I personally reject the idea of any bear species hunting and killing pachyderms. Bears are simply not built for hunting prey animals of such proportions. Unlike the big cats, a bear cannot leap upon his prey and cling to it with 'Velcro paws'. When a bear fights a herbivore, it is a very basic wrestling match of brute strength vs brute strength. In the ancient Roman arena, a European grizzly was once pitted against a rhinoceros. It was not a fight, but simply a killing. The rhino plowed through the bear like a freight train over a dog.
The arena pitted match between grizzly and rhino is spoken of in the book, 'Bear, History of a Fallen King'. I have also read the actual contents of the ages-old records ( translated into English ) years ago found by the poster 'Charger1'. Search as I might online, I cannot find it.
Bear jaw srength: ( Asian bear likely a sloth bear ).  *This image is copyright of its original author
The Grizzly, Our Greatest Wild Animal by Enos Mills.
In the grizzly bear we have the leading animal of North America, and one who might well be put at the head of the wild life of the earth. He has brain and brawn. He is self-contained and is prepared for anything. He makes an impressive appearance. He looks capable. He is bulk, agility, strength, endurance, repose, courage, enthusiasm, and curiosity. He is a master fighter if forced to defend himself. But, a century ago, fifty years ago, or today, one could ramble the grizzly's territory in safety - unless attempting to kill a grizzly. The grizzly objects to being killed. If he is surprised or crowded so that he sees no escape, if the cubs are in danger or the mother thinks they are, or if the bear is wounded, there will be a fight or a retreat; and the grizzly will not be the one retreating. Almost every animal - wild or domestic - will fight if cornered or if he thinks himself cornered. Before the days of the repeating rifle the grizzly boldly wandered over his domain as absolute master; there was nothing for him to fear; not an aggressive foe existed. But, being ever curious, he hastened to examine whatever interested him. But is the grizzly ferocious? All the firsthand evidence I can find says he is not. Speaking from years of experience with him my answer is emphatically, "No!" Nearly every one whom a grizzly has killed went out with the special intention of killing a grizzly. The majority of people who hold the opinion that he is not ferocious are those who studied him without attempting to kill him; while the majority who say that he is ferocious are those who have killed or attempted to kill him. 
@BorneanTiger I pressed wrong icon here. Your posting about short-faced bear was relevant in this thread. You can copy that article from short-faced bear thread and put it back here if you like. My bad, sorry, when looking a bit of threads in order to keep right content in right places.
The South American short-faced bear was believed to have been the largest bear ever to have existed. A skeleton was found in Buenos Aires Province, Argentina, in 1935, and paleontologists Blaine Schubert (from East Tennessee State University in Johnson City, Tennessee, the United States of America) and Leopoldo Soibelzon (from Argentina), used its huge humerus, about the size of that of an elephant to estimate the bear's weight as being 3,500 lbs (1,587.6 kg). By contrast, the North American short-faced bear was estimated to have weighed up to 2,500 lbs (1,134.0 kg): https://news.nationalgeographic.com/news...s-science/
Paleontologist Leopoldo Soibelzon holds the humerus (upper arm bone) of a South American short-faced bear next to that of an elephant: North American short-faced bear: https://www.pinterest.co.uk/pin/369717450650972070/
yes, the South american short faced bear (Arctotherium Angustidens), that single specimen found in Buenos Aires, estimated at about 3500 lbs based on the humerus, is clearly the king of the bears in all of history.
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