A large boar gives its salmon prey a hug before "processing" it for ingestion.
Grizzlies use a number of different handling techniques when feeding on salmon. In most cases, the savvy “fisherbear” will grasp its prize in its jaws and carry it from the waterway to the shore, a gravel bar or surrounding grassy meadow/woodland (subordinate grizzlies, in the presence of conspecifics, are often more likely to move farther from the capture site than larger, more dominant bears). They then place their catch on the ground and stand on it with the fore paws. How the prey fish is processed may vary from one individual to the next or from one location to another. In many cases the first thing a bear will do is bite down on the posterior region of the fish and remove the tail section. Another body tissue targeted early in the handling process is the skin. To skin its quarry, the bear will grasp the skin with the incisors and pull upward, peeling the integument from the salmon’s body.
If food is in short supply (e.g., it is early in the salmon run or if fish numbers are down) the bear will consume the entire fish. If food is abundant, the bruin may select the choicest parts of the fish and leave much of its behind for scavenging birds, other mammals or even other bears (e.g., subordinate individuals or those that are poor at fishing). As mentioned in other posts, the skin is preferred as are the brains, but rather than ingesting the entire head, the bear often bites through the top of the cranium and laps out the brain or plucks them out with its incisors (see video footage below).
Not all bears take the time to leave the stream to eat their prize. It is not uncommon to see a bear, standing in knee deep water, clamping the fish against the front foreleg with the opposite paw (some bears employ this technique when eating fish on shore). The bear then rips the fish apart, one bite at a time. If the water where a fish is captured is shallow enough, some bears will pin the fish to the stream bed, while in a state of repose, and then stick their head underwater and rip pieces from their piscine prize (the bear will raise its head to masticate and then submerge to take another bite).
I have noticed that in many cases the fish rarely struggle much after being trapped in the bear’s jaws. They seem to go limp. They may flop about if the bear should drop them on the shore before pinning them down to eat, but otherwise they resist very little while in the jaws of the bruin. (I did see occasions where they fish would struggle if a bear bit down on the upper back.)
In the video featured below, you will see various fishing methods and some of these handling methods employed by a number of different Katmai brown bears. A few things to look for: there is a sequence of video that shows a big brown bear deftly removing the brain from a fish. There is a scarred, big boar diving into a deep river pool from the shoreline and submerging in an attempt to capture its slippery quarry (he finally succeeds in capturing a "spent" fish in the video and stands on its hind feet as it tears the fish apart). Toward the end of the video, you will see a large boar launching some of its great bulk from the river and plunging back into the water with fore legs outstretched. At one point, it has herded a big school of salmon along the river bank and appears to be trying to push some of the fish onto the shoreline. Turn up the sound and enjoy!
A sow with her older cubs attempts to teach them to fish, although they prefer to play and loot their mother's catch.
Geographic’s fishing grounds were also home to a vivacious family unit, consisting of a sow and a pair of ~ 2 1/2 year olds. The mother was an efficacious “fisherbear,” while her cubs did little fishing. Instead, they spent much of their time grappling with each other like hairy Sumo wrestlers! When they were not playing, they were shadowing their mom and stealing any fish that she hauled in. Most of the time she would let them take off with her catch, although she did occasionally attempt to wolf down some of her piscine prey before she was looted by her greedy brood. On one occasion she lost her patience and cuffed one of her overzealous offspring before giving in and letting go of her fish (see video below). Occasionally, the two hooligans attempted to include mom in their frolicsome behavior. She complied a couple of times, jawing at her young assailants.
A trio of grizzlies: a sow with her two offspring (these to youngsters are probably 32 months old). Note how she does all of the fishing, while they benefit from the fruits of her labor! Compare these two laggards with the adolescent fishing machine below.
In contrast to these impish, 2.5-year olds, we observed an amazing young bear that was a fishing machine! This bruin was a ~ 1.5 year old (usually referred to as a yearling) with a light colored (nearly blonde) mother. The pair initially made their presence known when the mother, with the cub trailing behind, were observed chasing another bear. They gave up their half-hearted chase and began to slowly meander toward the prime fishing area. Once they arrived at the river bank, it was not long before the yearling was chasing and even catching salmon! (There were few other bears in the area at the time.) The mother bear seemed to lag behind the young bear, keeping close enough to protect its progeny if the need arised, but yet far enough away to allow it to learn some life skills. The young bear was such an enthusiastic piscator that at one point it had a fish in its mouth, while it attempted to capture a second salmonid (see the video below)!
The fishing exploits of an ~ 1.5-year old (yearling) bear - this young bruin was a very effective fisherman, as you will see in the video above.
This series of photos is intended to demonstrate just how variable the brown bear is in a single population - all of these bears were photographed last year in early August along the Katmai coast. A young adult brown bear is shown above (sex unknown). Photo by Scott W. Michael.
An adult female known as Ms. Hook (she had two spring cubs at this time). Photo by Scott W. Michael.
Queenie, an elderly sow. Photo by Scott W. Michael.
A young adult male. Photo by Scott W. Michael.
Adult boar named Mickey. Photo by Scott W. Michael.
A large boar (in his prime) dubbed Pythagoras. Photo by Scott W. Michael.
A very large, older boar. Dripping saliva is visible resulting from jaw injury. Scott W. Michael.
Although sporting some nicks and cuts, this boar is in his prime - this is Tank. Scott W. Michael.
Ursus arctos is one of the most revered and feared beasts on earth. This mammal has been given numerous appellations, including grizzly, brown, coastal brown, Alaska brown and Kodiak bear. As a neophyte to bear classification, I found myself very confused by the common vernacular, as well as the scientific nomenclature applied to this bruin. How many species or subspecies are there and do these common names represent disparate populations?
It turns out that all of these common names refer to a single species - Ursus arctos. Typically, the term brown bear (as well as coastal and Alaskan brown bear) is applied to U. arctos populations that live in coastal Alaska, while Kodiak bear is used for “brownie” populations that live in the Kodiak Island archipelago (this includes the islands of Kodiak, Afognak, and Shuyak). Grizzly is usually reserved for U. arctos populations in the interior of Alaska, in Canada and the lower 48 states. While you can call them whatever common name you wish, they are all Ursus arctos.
OK - HOW MANY SUBSPECIES?
So they all fall under the single binomial Ursus arctos - but are brown and grizzly bears different enough to warrant distinct subspecies status? And how about the Kodiak bear – doesn’t it represent a different subspecies? (OK, I know many of you are starting to suffer from brain fog because of taxonomic overload, but I enjoy this stuff, so bear with me!)
Traditionally, subspecies have been defined as populations that differ slightly from one another, but that are not disparate enough to be elevated to the level of distinct species. In most cases, a subspecies represents a group of individuals that has been isolated from the main population long enough to exhibit some degree of change, but yet if they breed with members of the original population they will still produce viable offspring.
There has been much debate about how many subspecies of U. arctos actually exist in North America. In the early twentieth century (1918 to be exact) it was proposed that there were 86 subspecies of U. arctos in North America alone! This classification scheme was soon shot to pieces by the taxonomically-inclined, leading bruin biologists to recognize only two subspecies: the mainland populations, which were recognized as Ursus arctos horribilis, and the bear population of the Kodiak Island archipelago, which were referred to as U. a. middendorffi.
So, everything appeared to be as clear as mud until DNA analysis came on the scene. DNA has a biochemical signature that enables scientists to distinguish species and study their degree of relatedness. Recently, using mitochondrial DNA, researchers struck a body blow to the widely accepted North American-Ursus arctos classification scheme. These molecular surveys indicate that there is actually only one subspecies of brown bear in all of North America – this subspecies should be called Ursus arctos arctos (no more horribilis or middendorffi).
In a nutshell, this means that the grizzly bear, Kodiak bear and brown bear are all the same beast. It is a wide-ranging subspecies that does not only roam throughout North America, it is also found over much of Eurasia as well. That’s right, U. arctos arctos is a circum-global species, having been reported from the Balkans, Caucasus, Carpathians, Pyrenees, Italy (Abruzzo and the Benta Mountains), the Baltic States, Scandinavia (excluding Denmark), Greece, Syria, Russia and the countries of the Tibetan plateau (China, Tibet and Nepal). That said, there are a number of other valid subspecies on the European and Asian continents. (A side note: another very odd conclusion the molecule purveyors came to is that certain populations of brown bears are more closely related to the polar bear [Ursus maritimus] then they are to other brown bears! Now my head hurts!)
AMAZING VARIABILITY
While it may be that brown and grizzly bears are not distinct on the molecular level, some bear buffs still insist that the inland grizzly and coastal brown bears are different animals. There is no doubt, that some individuals from coastal regions do not look like their inland kin. A male coastal brown bear often has a more elongated neck, longer legs, and more protuberant face than its landlocked “cousin,” while inland boars are often more compact, with a shorter neck, shorter appendages and more concave face. But when it comes to physical appearances, there are no hard fast rules that can be consistently used to separate the coastal and inland populations.
This incredible variability in U. arctos populations is acutely demonstrated by the studies of Dr. Ian Sterling and Andrew DeRocher. These researchers examined a set of male U. arctos skulls from the Caucus Mountains, Russia. They noted that while some skulls looked like those of a “classic” brown bear, there was also a skull that resembled a panda (with short face and high profile) and another that looked more like a wolf cranium (i.e., it was more elongate and slender)!
Above, I mentioned that in 1918, a researcher described 86 different “species” of brown and grizzly bears in North America. Most of his research was based on the examination of skulls at the National Museum (sometimes only a single specimen of a particular “species”). Another researcher came-up with an even more elaborate classification scheme – he concluded that the skeletons of extinct and modern day brown bears he examined represented 232 distinct ursid species. In actual fact they all belonged to the highly variable U. arctos!
You only have to look at the photos of the brown bears in this blog (I have included a number of shots above) to see that most grizzlies do not look exactly alike. In fact, individuals are often so unique in appearance that bear-viewers regularly name them and readily recognize them from one year to the next. Some individuals have big ears; in others the ears are relatively petite. The bodies of some are long and lanky, while those of others are short and squat. Some have a long, prominent snout; others have the “classic” grizzly “dish” (concave) face. Some of these characteristics also change from spring to fall (e.g., bears get girthy as they pile on weight for the winter) and as the bears age (e.g., subadult males tend to be more gracile and finely built than males in their prime). The color of the pelage is not a constant either -there are blond, brunette, black furred and, on rare occasions, even white brown bears! In conclusion, while there may be differences between some individuals in coastal and inland population, you cannot consistently distinguish between the different populations.
A large boar gives its salmon prey a hug before "processing" it for ingestion. 
