The Rae Craton is an Archean craton located in northern Canada , north of the Superior Craton .
61-613: The Ungava Peninsula , situated on the northeast portion of the Canadian Shield , is where the Rae Province connects with the Superior Province. This palaeogeography article is a stub . You can help Misplaced Pages by expanding it . This plate tectonics article is a stub . You can help Misplaced Pages by expanding it . Ungava Peninsula The Ungava Peninsula , officially Péninsule d'Ungava ,
122-416: A black bear sees a grizzly coming, it either turns tail and runs or climbs a tree. Black bears are not strong competition for prey because they have a more herbivorous diet. Confrontations are rare because of the differences in size, habitats, and diets of the bear species. When this happens, it is usually with the grizzly being the aggressor. The black bear will only fight when it is a smaller grizzly such as
183-460: A carcass, which is commonly an elk killed by wolves. The grizzly bear uses its keen sense of smell to locate the kill. As the wolves and grizzly compete for the kill, one wolf may try to distract the bear while the others feed. The bear then may retaliate by chasing the wolves. If the wolves become aggressive with the bear, it is normally in the form of quick nips at its hind legs. Thus, the bear will sit down and use its ability to protect itself in
244-687: A female scent difficult in such low population densities. Population fragmentation of grizzlies may destabilize the population from inbreeding depression . The gestation period for grizzly bears is approximately 180–250 days. Litter size varies between one and four cubs, typically comprising twins or triplets. Cubs are always born in the mother's winter den while she is in hibernation. Female grizzlies are fiercely protective of their cubs, being able to fend off predators including larger male bears. Cubs feed entirely on their mother's milk until summer comes, after which they still drink milk but begin to eat solid foods. Cubs gain weight rapidly during their time with
305-466: A full circle. Rarely do interactions such as these end in death or serious injury to either animal. One carcass simply is not usually worth the risk to the wolves (if the bear has the upper hand due to strength and size) or to the bear (if the wolves are too numerous or persistent). While wolves usually dominate grizzly bears during interactions at wolf dens, both grizzly and black bears have been reported killing wolves and their cubs at wolf dens even when
366-615: A grizzly in Colorado since 1979. Other provinces and the United States may use a combination of methods for population estimates. Therefore, it is difficult to say precisely what methods were used to produce total population estimates for Canada and North America, as they were likely developed from a variety of studies. The grizzly bear currently has legal protection in Mexico , European countries , some areas of Canada, and in all of
427-531: A local extinction in Beringia ~33,000 BP, two closely related lineages repopulated Alaska and northern Canada from Eurasia after the Last Glacial Maximum (>25,000 BP). In the 19th century, the grizzly was classified as 86 distinct species. By 1928 only seven grizzly species remained, and by 1953, only one species remained globally. However, modern genetic testing reveals the grizzly to be
488-580: A male in the summer, the female delays embryo implantation until hibernation, during which miscarriage can occur if the female does not receive the proper nutrients and caloric intake. On average, females produce two cubs in a litter and the mother cares for the cubs for up to two years, during which the mother will not mate. Once the young leave or are killed, females may not produce another litter for three or more years, depending on environmental conditions. Male grizzly bears have large territories , up to 4,000 km (1,500 sq mi), making finding
549-511: A more protein -enriched diet in coastal areas potentially grow larger than inland individuals. Grizzly bears also readily scavenge food or carrion left behind by other animals. Grizzly bears will also eat birds and their eggs, and gather in large numbers at fishing sites to feed on spawning salmon. They frequently prey on baby deer left in the grass, and occasionally they raid the nests of raptors such as bald eagles . Coastal Canadian and Alaskan grizzlies are larger than those that reside in
610-555: A parallel fashion. The peninsula was not deglaciated until 6,500 years ago (11,500 years after the Last Glacial Maximum ) and is believed to have been the prehistoric centre from which the vast Laurentide Ice Sheet spread over most of North America during the last glacial epoch. The Unavuk Peninsula is part of the Nunavik proposed autonomous area of Quebec. The Ungava Peninsula has an estimated population of 10,000 inhabitants. These are 90% Inuit , and live in 12 villages spread along
671-447: A period of hyperphagia , before going into hibernation. The bear often waits for a substantial snowstorm before it enters its den: such behavior lessens the chances that predators will find the den. The dens are typically at elevations above 1,800 meters (5,900 ft) on north-facing slopes. There is some debate among professionals as to whether grizzly bears technically hibernate: much of this debate revolves around body temperature and
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#1732772818416732-466: A subspecies of the brown bear ( Ursus arctos ). Biologist R.L. Rausch found that North America has but one species of grizzly. Therefore, everywhere it is the "brown bear"; in North America, it is the "grizzly", but these are all the same species, Ursus arctos . In 1963, Rausch reduced the number of North American subspecies to one, Ursus arctos middendorffi . Further testing of Y-chromosomes
793-492: A yearling or when the black bear has no other choice but to defend itself. There is at least one confirmed observation of a grizzly bear digging out, killing, and eating a black bear when the latter was in hibernation. The segregation of black bear and grizzly bear populations is possibly due to competitive exclusion. In certain areas, grizzly bears outcompete black bears for the same resources. For example, many Pacific coastal islands off British Columbia and Alaska support either
854-609: Is 48 km/h (30 mph). In addition, they can climb trees. Although grizzlies are of the order Carnivora and have the digestive system of carnivores, they are normally omnivores : their diets consist of both plants and animals. They have been known to prey on large mammals, when available, such as moose , elk , caribou , white-tailed deer , mule deer , bighorn sheep , bison , and even black bears , though they are more likely to take calves and injured individuals rather than healthy adults. Grizzly bears feed on fish such as salmon , trout , and bass , and those with access to
915-500: Is a longterm management plan to reintroduce the bears to North Cascades National Park . The grizzly bear's original range included much of the Great Plains and the southwestern states , but it has been extirpated in most of those areas. Combining Canada and the United States, grizzly bears inhabit approximately half the area of their historical range. Although the once-abundant California grizzly bear appears prominently on
976-512: Is between 198 cm (78 in) and 240 cm (94 in), with an average shoulder height of 102 cm (40 in) and hindfoot length of 28 cm (11 in). Newborn bears may weigh less than 500 g (18 oz). Although variable in color from blond to nearly black, grizzly bear fur is typically brown with darker legs and commonly white or blond tipped fur on the flank and back. Grizzly bears overlap with Black Bears in range, but there are numerous factors that can differentiate
1037-439: Is due to an influx of legumes , such as Hedysarum , which the grizzlies consume in massive amounts. When food sources become scarcer, however, they separate once again. The relationship between grizzly bears and other predators is mostly one-sided; grizzly bears will approach feeding predators to steal their kill. In general, the other species will leave the carcasses for the bear to avoid competition or predation. Any parts of
1098-634: Is extremely cold ( Dfc in the Köppen climate classification ) because the Labrador Current keeps the region (and all of northern Québec ) colder in the summer than other regions at comparable latitudes: Grizzly bear The grizzly bear ( Ursus arctos horribilis ), also known as the North American brown bear or simply grizzly , is a population or subspecies of the brown bear inhabiting North America . In addition to
1159-1133: Is in Denali National Park and Preserve , where grizzlies chase, pounce on, and dig up Arctic ground squirrels to eat. In some areas, grizzly bears prey on hoary marmots , overturning rocks to reach them, and in some cases preying on them when they are in hibernation . Larger prey includes bison and moose , which are sometimes taken by bears in Yellowstone National Park . Because bison and moose are dangerous prey, grizzlies usually use cover to stalk them and/or pick off weak individuals or calves. Grizzlies in Alaska also regularly prey on moose calves, which in Denali National Park may be their main source of meat. In fact, grizzly bears are such important predators of moose and elk calves in Alaska and Yellowstone that they may kill as many as 51 percent of elk or moose calves born that year. Grizzly bears have also been blamed in
1220-448: Is not uncommon to encounter grizzlies in Alaska weighing 540 kg (1,200 lb). Grizzlies in Alaska supplement their diet of salmon and clams with sedge grass and berries . In areas where salmon are forced to leap waterfalls, grizzlies gather at the base of the falls to feed on and catch the fish. Salmon are at a disadvantage when they leap waterfalls because they cluster together at their bases and are therefore easier targets for
1281-412: Is required to yield an accurate new taxonomy with different subspecies. Coastal grizzlies, often referred to by the popular but geographically redundant synonym of "brown bear" or "Alaskan brown bear" are larger and darker than inland grizzlies, which is why they, too, were considered a different species from grizzlies. Kodiak Grizzly Bears were also at one time considered distinct. Therefore, at one time
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#17327728184161342-537: Is situated on the northeast portion of the Canadian Shield where the Rae Province connects with the Superior Province. The region is composed of Archean rocks (ca. 2.7–2.9 Ga) from the Douglas Harbour Domain (see Superior Craton ). The Archean rocks are overlain by Paleoproterozoic supracrustal sequences (ca. 1.8–2.1 Ga) and intruded by Paleoproterozoic diabase dykes (ca. 2.0–2.2 Ga). The supracrustal rocks comprise nappes that form part of
1403-595: Is the far northwestern part of the Labrador Peninsula of the province of Quebec , Canada. Bounded by Hudson Bay to the west, Hudson Strait to the north, and Ungava Bay to the east, it covers about 252,000 km (97,000 sq mi). Its northernmost point is Cape Wolstenholme , which is also the northernmost point of Quebec. The peninsula is also part of the Canadian Shield , and consists entirely of treeless tundra dissected by large numbers of rivers and glacial lakes, flowing generally east–west in
1464-434: Is unique because it is the only example where Rocky Mountain grizzlies feed on spawning salmonid fish. However, grizzly bears themselves and invasive lake trout threaten the survival of the trout population and there is a slight chance that the trout will be eliminated. Grizzly bears occasionally prey on small mammals, such as marmots , ground squirrels , lemmings , and voles . The most famous example of such predation
1525-589: The Alaska Peninsula brown bear ( U. a. gyas ), Kodiak bear ( U. a. middendorffi ), Mexican grizzly bear ( U. a. nelsoni ), ABC Islands bear ( U. a. sitkensis ), and Stickeen brown bear ( U. a. stikeenensis ). One study based on mitochondrial DNA recovered no distinct genetic groupings of North American brown bears, implying that previous grizzly bear subspecies designations are unwarranted and these bears should all be considered populations of U. a. horribilis . The only genetically anomalous grouping
1586-590: The Kamchatka brown bear than to other North American brown bears. Until the systematics of North American brown bears is studied in more depth, other North American subspecies have been provisionally considered separate from U. a. horribilis . Grizzly bears are some of the largest subspecies of brown bear, only being beaten by the Kamchatka brown bears and the Kodiak bears . Grizzly bears vary in size depending on timing and populations. The largest populations are
1647-489: The Rocky Mountains . This is due, in part, to the richness of their diets. In Yellowstone National Park in the United States, the grizzly bear's diet consists mostly of whitebark pine nuts , tubers , grasses, various rodents , army cutworm moths, and scavenged carcasses. None of these, however, match the fat content of the salmon available in Alaska and British Columbia. With the high fat content of salmon, it
1708-492: The salmon spawn . Females (sows) produce one to four young (usually two) that are small and weigh only about 450 g (16 oz) at birth. A sow is protective of her offspring and will attack if she thinks she or her cubs are threatened. Grizzly bears have one of the lowest reproductive rates of all terrestrial mammals in North America. This is due to numerous ecological factors. Grizzly bears do not reach sexual maturity until they are at least five years old. Once mated with
1769-492: The European settlers arrived. However, population size has since significantly decreased due to hunting and habitat loss. In 2008, it was estimated there were 16,000 grizzly bears. A revised Grizzly bear count in 2012 for British Columbia was 15,075. Population estimates for British Columbia are based on hair-snagging, DNA-based inventories, mark-and-recapture , and a refined multiple regression model. In 2003, researchers from
1830-708: The Ungava and Labrador troughs . In the zone east of the Labrador Trough axis, the Paleoproterozoic deformation reworked the Archean rocks of the Douglas Harbour Domain, as well as the Paleoproterozoic diabase dykes. The metamorphic conditions which parallel the deformation increase from west to east and from middle amphibolite to granulite facies . U–Pb isotope analyses of zircon yield secondary ages around 1790 Ma. These results are interpreted as
1891-604: The United States. However, it is expected that repopulating its former range will be a slow process, due to various reasons, including the bear's slow reproductive habits and the effects of reintroducing such a large animal to areas prized for agriculture and livestock. Grizzly bears hibernate for five to seven months each year (except where the climate is warm—the California grizzly did not hibernate). During this time, female grizzly bears give birth to their offspring, who then consume milk from their mother and gain strength for
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1952-603: The University of Alberta spotted a grizzly on Melville Island in the high Arctic, which is the most northerly sighting ever documented. Around 60,000 wild grizzly bears are located throughout North America, 30,000 of which are found in Alaska . and up to 29,000 live in Canada. The Alaskan population of 30,000 individuals is the highest population of any province / state in North America. Populations in Alaska are densest along
2013-660: The Yukon, the Northwest Territories, Nunavut , and the northern part of Manitoba . An article published in 1954 suggested they may be present in the tundra areas of the Ungava Peninsula and the northern tip of Labrador - Quebec . In British Columbia, grizzly bears inhabit approximately 90% of their original territory. There were approximately 25,000 grizzly bears in British Columbia when
2074-583: The ability of the bears to move around during hibernation on occasion. Grizzly bears can "partially" recycle their body wastes during this period. Although inland or Rocky Mountain grizzlies spend nearly half of their life in dens, coastal grizzlies with better access to food sources spend less time in dens. In some areas where food is very plentiful year round, grizzly bears skip hibernation altogether. Except for females with cubs, grizzlies are normally solitary , active animals, but in coastal areas, grizzlies gather around streams, lakes, rivers, and ponds during
2135-474: The age of metamorphism and indicate a reactivation of the northeastern margin of the Superior Province during a Paleoproterozoic tectono - metamorphic event, resulting from probable continental collision. (Madore, 2001). Pingualuit impact crater is located on the peninsula. The Ungava brown bear , an extinct population of the grizzly bear , is named after this peninsula. The climate
2196-583: The black bear or the grizzly, but rarely both. In regions where both species coexist, they are divided by landscape gradients such as the age of forest, elevation, and land openness. Grizzly bears tend to favor old forests with high productivity, higher elevations and more open habitats compared with black bears. However, a bear shot in autumn 1986 in Michigan was thought by some to be a grizzly×black bear hybrid , due to its unusually large size and its proportionately larger braincase and skull, but DNA testing
2257-457: The brown bear around the world. Meriwether Lewis and William Clark first described it as grisley , which could be interpreted as either " grizzly " (i.e., "grizzled"—that is, with grey-tipped hair) or " grisly " ("fear-inspiring", now usually "gruesome"). The modern spelling supposes the former meaning; even so, naturalist George Ord formally classified it in 1815 as U. horribilis for its character. Several studies have been conducted on
2318-422: The carcass left uneaten are scavenged by smaller animals. With the reintroduction of gray wolves to Yellowstone, many visitors have witnessed a once common struggle between a keystone species , the grizzly bear, and its historic rival, the gray wolf. The interactions of grizzly bears with the wolves of Yellowstone have been under considerable study. Typically, the conflict will be in the defence of young or over
2379-460: The coast also forage for razor clams , and frequently dig into the sand to seek them. During the spring and fall, directly before and after the salmon runs, berries and grass make up the mainstay of the diets of coastal grizzlies. Inland grizzlies may eat fish too, most notably in Yellowstone grizzlies eating Yellowstone cutthroat trout . The relationship with cutthroat trout and grizzlies
2440-750: The coast tend to be larger while inland grizzlies tend to be smaller. The Ussuri brown bear ( U. a. lasiotus ), inhabiting the Ussuri Krai , Sakhalin , the Amur Oblast , the Shantar Islands , Iturup Island , and Kunashir Island in Siberia , northeastern China , North Korea , and Hokkaidō in Japan , is sometimes referred to as the "black grizzly", although it is no more closely related to North American brown bears than other subspecies of
2501-601: The coast, where food supplies such as salmon are more abundant. The Admiralty Island National Monument protects the densest population: 1,600 bears on a 1,600 square-mile island. The majority of Canada's grizzlies live in British Columbia. In the lower 48 United States, around 1,000 are found in the Northern Continental Divide in northwestern Montana . About 1,000 more live in the Greater Yellowstone Ecosystem in
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2562-580: The coast. The largest village, Kuujjuaq , is the capital of the Kativik Regional Government , which includes all of the peninsula. The peninsula's offshore islands are part of the Nunavut Territory . The region is accessible by air services, with links to southern Québec, and seasonal shipping when sea-ice breaks up. Thick permafrost prevents the use of conventional building techniques in some areas. The Ungava Peninsula
2623-538: The coastal grizzlies in the Alaskan peninsula, with males weighing 389 kilograms (858 lb) and females weighing 207 kilograms (456 lb). The populations in northern interior Canada are much smaller, with males weighing 139 kilograms (306 lb) and females weighing 95 kilograms (209 lb). This is actually similar to the American black bear population of the area. Average total length in this subspecies
2684-425: The decline of elk in Yellowstone National Park when the actual predators were thought to be gray wolves . In northern Alaska, grizzlies are a significant predator of caribou , mostly taking sick or old individuals or calves. Several studies show that grizzly bears may follow the caribou herds year-round in order to maintain their food supply. In northern Alaska, grizzly bears often encounter muskox . Despite
2745-533: The diets of grizzly bears vary extensively based on seasonal and regional changes, plants make up a large portion of them, with some estimates as high as 80–90%. Various berries constitute an important food source when they are available. These can include blueberries , blackberries ( Rubus fruticosus ), salmon berries ( Rubus spectabilis ), cranberries ( Vaccinium oxycoccos ), buffalo berries ( Shepherdia argentea ), soapberries ( Shepherdia canadensis ), and huckleberries ( Vaccinium parvifolium ), depending on
2806-487: The dominant mitochondrial grouping south of subarctic North America. Genetic divergences suggest brown bears first migrated south during MIS-5 (~92,000 - 83,000 BP) upon the opening of the ice-free corridor, with the first fossils being near Edmonton (26,000 BP). Other mitochondrial lineages appear later- the Alexander and Haida Gwaii archipelagoes have an endemic lineage, which first appears around 20,000 BP. After
2867-425: The environment. Insects such as ladybugs , ants, and bees are eaten if they are available in large quantities. In Yellowstone National Park, grizzly bears may obtain half of their yearly caloric needs by feeding on miller moths that congregate on mountain slopes. When food is abundant, grizzly bears will feed in groups. For example, many grizzly bears will visit meadows right after an avalanche or glacier slide. This
2928-464: The fact that muskox do not usually occur in grizzly habitat and that they are bigger and more powerful than caribou, predation on muskox by grizzlies has been recorded. Grizzlies along the Alaskan coast also scavenge on dead or washed up whales. Usually such incidents involve only one or two grizzlies at a carcass, but up to ten large males have been seen at a time eating a dead humpback whale . Dead seals and sea lions are also consumed. Although
2989-674: The genetic history of the grizzly bear. Classification has been revised along genetic lines. There are two morphological forms of Ursus arctos : the grizzly and the coastal brown bears, but these morphological forms do not have distinct mtDNA lineages. The genome of the grizzly bear was sequenced in 2018 and found to be 2,328.64Mb (mega-basepairs) in length, and contain 30,387 genes. Brown bears originated in Eurasia , and first migrated to North America between 177,000 BP ~ 111,000 BP. Most grizzly bears belong to this initial population of North American brown bear (clade 4), which continues to be
3050-471: The grizzlies. Grizzly bears are well-documented catching leaping salmon in their mouths at Brooks Falls in Katmai National Park and Preserve in Alaska. They are also very experienced in chasing the fish around and pinning them with their claws. At such sites such as Brooks Falls and McNeil Falls in Alaska, big male grizzlies fight regularly for the best fishing spots. Grizzly bears along
3111-725: The late 19th and early 20th centuries, of cougars and grizzly bears killing each other in fights to the death. The other big cat present in the United States which might pose a threat to bears is the jaguar ; however, both species have been extirpated in the regions of the Southwest where their former habitats overlapped, and grizzlies remain so far absent from the regions along the U.S.-Mexico border, where jaguars appear to be returning. Black bears generally stay out of grizzly territory , but grizzlies may occasionally enter black bear terrain to obtain food sources both bears enjoy, such as pine nuts, acorns, mushrooms, and berries. When
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#17327728184163172-472: The mainland grizzly ( Ursus arctos horribilis ), other morphological forms of brown bear in North America are sometimes identified as grizzly bears. These include three living populations—the Kodiak bear ( U. a. middendorffi ), the Kamchatka bear ( U. a. beringianus ), and the peninsular grizzly ( U. a. gyas )—as well as the extinct California grizzly ( U. a. californicus †) and Mexican grizzly (formerly U. a. nelsoni †). On average, grizzly bears near
3233-472: The mother—their weight will have increased from 4.5 to 45 kg (9.9 to 99.2 lb) in the two years spent with the mother. Mothers may see their cubs in later years but both avoid each other. The average lifespan for a male is estimated at 22 years, with that of a female being slightly longer at 26. Females live longer than males due to their less dangerous life; they do not engage in seasonal breeding fights as males do. The oldest known wild inland grizzly
3294-521: The remainder of the hibernation period. To prepare for hibernation, grizzlies must prepare a den and consume an immense amount of food because they do not eat during hibernation. Grizzly bears also do not defecate or urinate throughout the entire hibernation period. The male grizzly bear's hibernation ends in early to mid-March, while females emerge in April or early May. In preparation for winter, bears can gain approximately 180 kg (400 lb), during
3355-772: The state flag of California and was the symbol of the Bear Flag Republic before the state of California's admission to the Union in 1850, the subspecies or population is currently extinct. The last known grizzlies in California were killed in the Sierra foothills east of Fresno in the early 1920s. The killing of the last grizzly bear in Arizona in 1936 at Escudilla Mountain is included in Aldo Leopold 's Sand County Almanac . There has been no confirmed sighting of
3416-421: The thought was there were five different "species" of brown bear, including three in North America. It remains an open question how many subspecies of Ursus arctos are present in North America. Traditionally, the following have been recognized alongside U. a. horribilis proper: Alaskan brown bear ( U. a. alascensis ), California grizzly bear ( U. a. californicus ), Dall Island brown bear ( U. a. dalli ),
3477-570: The tri-state area of Wyoming, Idaho and Montana. There are an estimated 70–100 grizzly bears living in northern and eastern Idaho . In September 2007, a hunter produced evidence of one bear in the Selway-Bitterroot Wilderness ecosystem , by killing a male grizzly bear there. In the North Cascades ecosystem of northern Washington , grizzly bear populations are estimated to be fewer than 20 bears, but there
3538-510: The two: In North America, grizzly bears previously ranged from Alaska down to Mexico and as far east as the western shores of Hudson Bay ; the species is now found in Alaska , south through much of western Canada , and into portions of the northwestern United States (including Washington , Idaho , Montana , and Wyoming ), extending as far south as Yellowstone and Grand Teton National Parks . In Canada, there are approximately 25,000 grizzly bears occupying British Columbia , Alberta ,
3599-573: The wolves were acting in defence. Cougars generally give the bears a wide berth. Grizzlies have less competition with cougars than with other predators, such as coyotes, wolves, and other bears. When a grizzly descends on a cougar feeding on its kill, the cougar usually gives way to the bear. When a cougar does stand its ground, it will use its superior agility and its claws to harass the bear, yet stay out of its reach until one of them gives up. Grizzly bears occasionally kill cougars in disputes over kills. There have been several anecdotes, primarily from
3660-405: Was about 34 years old in Alaska; the oldest known coastal bear was 39, but most grizzlies die in their first year of life. Captive grizzlies have lived as long as 44 years. They have a tendency to chase fleeing animals, and although it has been said anecdotally that grizzly bears ( Ursus arctos horribilis ) can run at 56 km/h (35 mph), the maximum speed reliably recorded at Yellowstone
3721-540: Was the ABC Islands bear , which bears genetic introgression from the polar bear . A formal taxonomic revision was not performed, however, and the implied synonymy has not been accepted by taxonomic authorities. Furthermore, a recent whole-genome study suggests that certain Alaskan brown bears, including the Kodiak and Alaskan Peninsula grizzly bears, are members of a Eurasian brown bear lineage, more closely related to
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