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125-624: 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 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 ),
250-614: A 2.6 km (1.0 sq mi) area. To maximize food intake at these ecologically important areas, bears have learned to minimize fighting and fatal interactions by developing a complex communication (both verbal and body posturing) and social structure. Usually, Kodiak bears attempt to avoid encounters with people. The most notable exceptions to this behavior pattern occur when bears are surprised, threatened, or attracted by human food, garbage, or hunter-killed game. However, there has been an increase in Kodiak encounters due to increases in
375-416: 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
500-459: 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
625-686: 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
750-476: A few programs, most notably the Chinese government's one-child per family policy, have resorted to coercive measures. In the 1970s, tension grew between population control advocates and women's health activists who advanced women's reproductive rights as part of a human rights -based approach. Growing opposition to the narrow population control focus led to a significant change in population control policies in
875-465: 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
1000-614: 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
1125-666: A hind foot measurement of 46 cm (18 in). A large male Kodiak bear stands up to 1.5 m (4.9 ft) tall at the shoulder when it is standing on all four legs. When standing fully upright on its hind legs, a large male could reach a height of 3 m (9.8 ft). The largest verified size for a captive Kodiak bear was for a specimen that lived at the Dakota Zoo in Bismarck, North Dakota . Nicknamed "Clyde", he weighed 966 kg (2,130 lb) when he died in June 1987 at
1250-579: A killer bear in the movie Grizzly , stood 3.4 metres (11 ft) tall on its hind legs and was the largest bear in captivity at the time. This brown bear population only occurs on the islands of the Kodiak Archipelago ( Kodiak , Afognak , Shuyak , Raspberry , Uganik , Sitkalidak , and adjacent islands). The Kodiak bear population was estimated to include 3,526 bears in 2005, yielding an estimated archipelago-wide population density of 270 bears per 1000 km (700 per 1000 sq. mi). During
1375-550: A logging road began on Afognak Island, and timber harvesting began in 1977. In 1979, work began on an environmental impact statement for the Terror Lake hydroelectric project on Kodiak Island. That project included an earthen dam on Terror Lake with Kodiak National Wildlife Refuge and a 10 km (6 mi) tunnel through a mountain ridge to a penstock and powerhouse in the Kizhuyak River drainage. The hydro project
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#17327732917561500-574: 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
1625-509: 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
1750-445: 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
1875-412: A population of grizzly bears . Physiologically and physically, the Kodiak bear is very similar to the other brown bear subspecies, such as the mainland grizzly bear ( Ursus arctos horribilis ) and the extinct California grizzly bear ( U. a. californicus ), with the main difference being size, as Kodiak bears are on average 1.5 to 2 times larger than their cousins. Despite this large variation in size,
2000-587: A result of ANCSA and ANILCA were reinstated into the refuge, either through direct purchase or utilizing conservation easements. Lands were also purchased in America, Westtown, and Shuyak Islands and transferred into state ownership. The Kodiak Brown Bear Trust coordinated a coalition of sportsmen and other wildlife conservation groups from around the nation to lobby for the use of settlement funds to acquire Kodiak lands. The groups also directly contributed funding to protect small parcels of important bear habitat around
2125-409: A segment on two brown bear attacks. Both incidents involved hunters who were hunting by themselves and were returning to game they had killed previously, and left alone in order to continue hunting. One of the attacks was fatal, with the hunter being killed by the bear, and occurred on Uganik Island (November 3, 1999), which is part of the Kodiak archipelago. In the other incident, after being attacked by
2250-428: A settlement with the state and federal governments. Paradoxically, the impacts of the oil spill and the subsequent cleanup and settlement proved to be beneficial to bears on Kodiak. Bear-safety training exposed thousands of workers to factual information about bears, and money from the settlement fund was used for funding land acquisitions. By the close of the 20th century, over 80% of the refuge lands that had been lost as
2375-523: A single species ( Ursus arctos ). Genetic samples from bears on Kodiak have shown that they are most closely related to brown bears on the Alaska Peninsula and Kamchatka , Russia, and all brown bears roughly north of the US. Kodiak bears have been genetically isolated since at least the last ice age (10,000 to 12,000 years ago) and very little genetic diversity exists within the population. Although
2500-545: A variety of experts from agencies and receiving extensive public input, developed more than 270 recommendations for managing and conserving Kodiak bears. Despite the diversity of viewpoints expressed by members of the group, all of the recommendations were by consensus. The underlying themes of the recommendations were continued conservation of the bear population at its current level, increased education programs to teach people how to live with bears on Kodiak, and protection of bear habitat with allowances for continued human use of
2625-490: 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
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#17327732917562750-607: 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
2875-498: 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
3000-913: Is also known therefore as a gamodeme. This also implies that all members belong to the same species. If the gamodeme is very large (theoretically, approaching infinity), and all gene alleles are uniformly distributed by the gametes within it, the gamodeme is said to be panmictic. Under this state, allele ( gamete ) frequencies can be converted to genotype ( zygote ) frequencies by expanding an appropriate quadratic equation , as shown by Sir Ronald Fisher in his establishment of quantitative genetics. This seldom occurs in nature: localization of gamete exchange – through dispersal limitations, preferential mating, cataclysm, or other cause – may lead to small actual gamodemes which exchange gametes reasonably uniformly within themselves but are virtually separated from their neighboring gamodemes. However, there may be low frequencies of exchange with these neighbors. This may be viewed as
3125-509: 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
3250-538: Is derived from the Late Latin populatio (a people, a multitude), which itself is derived from the Latin word populus (a people). In sociology and population geography , population refers to a group of human beings with some predefined feature in common, such as location, race , ethnicity , nationality , or religion . In ecology , a population is a group of organisms of the same species which inhabit
3375-438: 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
3500-497: Is during May and June. They are serially monogamous (having one partner at a time), staying together from two days to two weeks. As soon as the egg is fertilized and divides a few times, it enters a state of suspended animation until autumn when it finally implants on the uterine wall and begins to grow again. Cubs are born in the den during January or February. Weighing less than 450 g (1 lb) at birth with little hair and closed eyes, they suckle for several months, emerging from
3625-413: Is from 181 to 318 kg (399 to 701 lb), and for males (boars), it is 272 to 635 kg (600 to 1,400 lb). Mature males average 477–534 kg (1,052–1,177 lb) over the course of the year, and can weigh up to 680 kg (1,500 lb) at peak times. Females are typically about 20% smaller and 30% lighter than males, and adult sizes are attained when they are six years old. Bears weigh
3750-464: Is much like other brown bears in intelligence, although its tendency to feed in large dense groups leads to more complex social behaviors. Kodiak bears are generally solitary in nature; however, when food is concentrated in small areas, such as along salmon spawning streams, grass/sedge flats, berry patches, a dead whale, or even an open garbage dump, they often occur in large groups. Along a few streams on Kodiak, up to 60 bears can be seen simultaneously in
3875-609: Is not even known to the nearest million, so there is a considerable margin of error in such estimates. Researcher Carl Haub calculated that a total of over 100 billion people have probably been born in the last 2000 years. Population growth increased significantly as the Industrial Revolution gathered pace from 1700 onwards. The last 50 years have seen a yet more rapid increase in the rate of population growth due to medical advances and substantial increases in agricultural productivity, particularly beginning in
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4000-459: Is not fair to encourage bears to be close to people during the summer, only to allow them to be shot in the fall. The Kodiak bear plan recognized bear hunting as a legitimate, traditional, and biologically justifiable activity. It recommended that agencies find ways to make bear hunting and bear viewing compatible on the archipelago. The bear is important to the Alutiiq people. Its Alutiiq name
4125-746: Is not listed as an endangered species by the Endangered Species Act of the U.S. Fish and Wildlife Service . Kodiak bear research and habitat protection is done cooperatively by the ADF&;G and Kodiak National Wildlife Refuge. Bear hunting is managed by the ADF&G, and hunting regulations are established by the Alaska Board of Game. Currently, a finely tuned management system distributes hunters in 32 different areas during two seasons (spring: April 1 – May 15, and fall: October 25 – November 30). Each year, about 4,500 people apply for
4250-500: 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
4375-611: Is often referred to as the demographic transition . Human population planning is the practice of altering the rate of growth of a human population. Historically, human population control has been implemented with the goal of limiting the rate of population growth. In the period from the 1950s to the 1980s, concerns about global population growth and its effects on poverty, environmental degradation , and political stability led to efforts to reduce population growth rates. While population control can involve measures that improve people's lives by giving them greater control of their reproduction,
4500-460: 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 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
4625-715: Is very likely that the world's population will stop growing before the end of the 21st century. Further, there is some likelihood that population will actually decline before 2100. Population has already declined in the last decade or two in Eastern Europe, the Baltics and in the former Commonwealth of Independent States. The population pattern of less-developed regions of the world in recent years has been marked by gradually declining birth rates. These followed an earlier sharp reduction in death rates. This transition from high birth and death rates to low birth and death rates
4750-579: 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 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 ),
4875-587: 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
5000-589: 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 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 ,
5125-480: 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
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5250-488: 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
5375-744: 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 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
5500-531: The United States Fish and Wildlife Service to a lesser extent, closely monitor the size and health of the population and the number of bears hunted in the state. Taxonomist C.H. Merriam was the first to recognize the Kodiak bear as a unique subspecies of the brown bear, and he named it " Ursus middendorffi " in honor of the celebrated Baltic naturalist, Dr. A. Th. von Middendorff . Subsequent taxonomic work merged all North American brown bears into
5625-489: 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
5750-569: The 1960s, made by the Green Revolution . In 2017 the United Nations Population Division projected that the world's population would reach about 9.8 billion in 2050 and 11.2 billion in 2100. In the future, the world's population is expected to peak at some point, after which it will decline due to economic reasons, health concerns, land exhaustion and environmental hazards. According to one report, it
5875-519: The 1990s and 2000s, the proportion increased to almost 9%. In the past 20 years, bear viewing has become increasingly popular on Kodiak and other parts of Alaska. The most accessible bear-viewing location on Kodiak, Frazer River , had over 1,100 people come in 2007. Visitor numbers have been increasing at about 10% annually and development of additional bear viewing areas on Kodiak is planned. Also, other bear viewing opportunities exist through air-taxi, charter boat, remote lodge, and trekking operations on
6000-417: 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 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
6125-491: The 496 permits offered for Kodiak bear hunts (two-thirds to Alaska residents, one-third to non-residents). Nonresidents are required to hire a registered guide who is authorized to hunt in a particular area, and this can cost from $ 10,000 to $ 22,000. All hunters must come into the Alaska Department of Fish and Game office in Kodiak before going into the field for a brief orientation and must check out before they leave
6250-590: The ADF&G officers who often have the full support of the local community. Illegal hunting and fishing is frowned upon by the community which maintains a healthy respect for the island's environmental laws, as well. Stiff penalties accompany illegal hunting and fishing. The island's remote location makes trafficking in illegal pelts difficult for would-be poachers. Since statehood, the reported number of Kodiak bears killed by hunters has ranged from 77 (1968–1969) to 206 (1965–1966). From 2000 to 2006, an average of 173 Kodiak bears were killed by hunters each year (118 during
6375-489: 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
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#17327732917566500-480: The Kodiak bear population as human activity in its range increases. The IUCN classifies the brown bear ( Ursus arctos) , of which the Kodiak is a subspecies, as being of " least concern " in terms of endangerment or extinction , though the IUCN does not differentiate between subspecies and thus does not provide a conservation status for the Kodiak population. The Alaska Department of Fish and Game however, along with
6625-496: The United States Census Bureau, the world population hit 6.5 billion on 24 February 2006. The United Nations Population Fund designated 12 October 1999 as the approximate day on which world population reached 6 billion. This was about 12 years after the world population reached 5 billion in 1987, and six years after the world population reached 5.5 billion in 1993. The population of countries such as Nigeria
6750-602: 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
6875-600: 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
7000-658: 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
7125-580: 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
7250-467: The age of 22. According to zoo director Terry Lincoln, Clyde probably weighed close to 1,089 kg (2,400 lb) a year earlier. He still had a fat layer of 9 in (23 cm) when he died. . Kodiak bears are the largest brown bear and are even comparable in size to polar bears . This makes Kodiak bears and polar bears both the two largest members of the bear family and the largest extant terrestrial carnivorans. The standard method of evaluating
7375-754: The archipelago as large areas were conveyed to the Native corporations. Federal management of the National Forest lands on Afognak was transferred to Native Corporation ownership with the passage of the Alaska National Interest Lands Conservation Act in 1980 (ANILCA), and the Kodiak National Wildlife Refuge lost control of 130,000 hectares (310,000 acres) of prime bear habitat (more than 17% of refuge lands). In 1975, construction of
7500-459: The archipelago they live. Almost a quarter of the adult bears forgo denning, staying somewhat active throughout the winter. Kodiak bears reach sexual maturity at age five, but most sows are over nine years old when they successfully wean their first litter. The average time between litters is four years. Sows continue to produce cubs throughout their lives, but their productivity diminishes after they are 20 years old. Mating season for Kodiak bears
7625-441: The archipelago when the land was locked into the ice age looked to the sea for their sustenance. At that time, Kodiak Natives (Alutiiqs) occasionally hunted bears, using their meat for food, hides for clothing and bedding, and teeth for adornment. Traditional stories often revolved around the similarity between bears and humans, and the mystical nature of bears because of their proximity to the spirit world. Russian hunters came to
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#17327732917567750-463: The archipelago, resulting in a surge of baseline and applied bear research on Kodiak through the 1980s and 1990s. Bears were not directly harmed by the Exxon Valdez oil spill in 1989, although some were displaced from traditional feeding and traveling areas by cleanup crews. No one was injured by a bear, and no Kodiak bears were killed. To mitigate the adverse impacts of the spill, Exxon reached
7875-417: The archipelago. Although bear-viewing is often considered a "nonconsumptive" use, it can have serious impacts on bear populations if it is not conducted properly. Most viewing occurs at places where bears congregate because of feeding opportunities that are critical to their survival. If some bears avoid these areas because people are there, those bears may not get the fat and protein they need to make it through
8000-423: The archipelago. Although the group's role is merely advisory, government management agencies expressed a commitment to implement all of the regulations that were feasible and within their legal jurisdictions. The International Union for Conservation of Nature Red List does not list subspecies. The brown bear species, of which the Kodiak subspecies is a member, is listed as Lower Risk or Least Concern. The Kodiak
8125-441: The area in the late 18th century to capitalize on the abundant fur resources. Bear hides were considered a "minor fur" and sold for about the same price as river otter pelts. The number of bears harvested increased substantially when sea otter populations declined and after the United States acquired Alaska in 1867, bear harvests on Kodiak increased, peaking at as many as 250 bears per year. Commercial fishing activities increased in
8250-458: The bear, the hunter stabbed it with a knife, then recovered their rifle and killed the attacking bear. This occurred on Raspberry Island, home to two full-service wilderness lodges. Prior to that, the last fatality was in 1921. About once every other year, a bear injures a person on Kodiak. In October 2021, a father and son hunting duo survived an attack from a Kodiak bear during an elk registration hunt on Afognak Island. Early human occupants of
8375-581: 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
8500-480: The brain, flesh, and eggs of salmon for their high nutritional value. In the late summer and early fall, bears consume several types of berries when they reach their ripest point, and have the highest levels of sugar. As climate change causes elderberries to ripen earlier, berry season is now overlapping with salmon season and some bears are abandoning salmon runs to focus on the berries. Bears also feed on wind-rowed seaweed and invertebrates on some beaches throughout
8625-480: The breaking up of a large sexual population (panmictic) into smaller overlapping sexual populations. This failure of panmixia leads to two important changes in overall population structure: (1) the component gamodemes vary (through gamete sampling) in their allele frequencies when compared with each other and with the theoretical panmictic original (this is known as dispersion, and its details can be estimated using expansion of an appropriate binomial equation ); and (2)
8750-421: 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
8875-597: 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
9000-536: 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
9125-500: The cubs die before they leave, with cannibalism by adult males being one of the major causes of death. Kodiak bears that have recently left their mothers, at ages 3–5 years, have high mortality rates with only 56% of males and 89% of females surviving. Most young female bears stay within or near their mother's home range, while most males move farther away. Most adult sows die of natural causes (56%), while most adult male bears are killed by hunters (91%). The oldest known male bear in
9250-403: The current population is healthy, productive, and has shown no overt adverse signs of inbreeding , it may be more susceptible to new diseases or parasites than other, more diverse brown bear populations. Hair colors range from pale blonde to orange (typically females or bears from southern parts of the archipelago) to dark brown. Cubs will often retain a white "natal ring" around their neck for
9375-495: 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
9500-493: The den in May or June, weighing 6.8–9.1 kilograms (15–20 pounds). Typical litter sizes on Kodiak are two or three cubs, with a long-term average of 2.4 cubs per litter. However, Kodiak bears have six functional nipples and can litter up to six cubs have been reported. Sows are sometimes seen with five or six cubs in tow, probably due to adopting cubs from other litters. Most cubs stay with their mothers for three years. Almost half of
9625-528: The diet and lifestyle of the Kodiak bear do not differ greatly from those of other brown bears. Kodiak bears have interacted with humans for centuries, especially hunters and other people in the rural coastal regions of the archipelago. The bears are hunted for sport and are encountered by hunters pursuing other species. Less frequently, Kodiak bears are killed by people whose property (such as livestock) or person are threatened. In recent history there has been an increasing focus on conservation and protection of
9750-532: 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
9875-513: The dilemma of conserving bears while protecting cattle, salmon, and people, President Franklin D. Roosevelt created the Kodiak National Wildlife Refuge by executive order in 1941. The 7,700 km (1,900,000 acres) refuge roughly encompasses the southwestern two-thirds of Kodiak Island, Uganik Island, the Red Peaks area on northwestern Afognak Island, and all of Ban Island. Alaska achieved statehood in 1959 and assumed responsibility for managing
10000-508: The early 1980s. Kodiak bear The Kodiak bear ( Ursus arctos middendorffi ), also known as the Kodiak brown bear and sometimes the Alaskan brown bear , inhabits the islands of the Kodiak Archipelago in southwest Alaska . It is one of the largest recognized subspecies or population of the brown bear , and one of the two largest bears alive today, the other being the polar bear . They are also considered by some to be
10125-424: 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
10250-461: 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
10375-405: The fall season and 55 in the spring season). Over 75% of those were males. An additional nine bears were reported killed annually in defense of life or property during the same time. The number of large, trophy-sized bears (total skull size at least 70 cm [28 inches]) killed by hunters in recent years has been increasing. In the 1970s, only 2.5% of the bears killed on Kodiak were trophy-sized; in
10500-465: The first few years of life. The Kodiak bear's color is similar to that of its close relatives, the mainland American Grizzly bear and Eurasian brown bears . While there is generally much variation in size between brown bears in different areas, most usually weigh between 115 and 360 kg (254 and 794 lb); the Kodiak bear illustrates island gigantism , commonly reaching sizes of 300 to 600 kg (660 to 1,320 lb). The size range for females (sows)
10625-407: The first to go to dens; males are the last. Males begin emerging from their dens in early April, while sows with new cubs may stay in dens until late June. Bears living on the north end of Kodiak Island tend to have longer denning periods than bears in the southern areas. Most Kodiak bears dig their dens in hill or mountain sides and they use a wide variety of denning habitats depending on which part of
10750-433: 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 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
10875-533: 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 the coast also forage for razor clams , and frequently dig into
11000-571: 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 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
11125-403: The island. Every bear that is legally killed on the archipelago must be inspected by an ADF&G wildlife biologist before it can be taken from the islands. Pelts receive a stamp from an ADF&G officer if the hunter and guide provide proper documentation to prove licensing. Pelts cannot be transported or legally preserved or sold without the official stamp. Hunting laws are strictly enforced by
11250-474: The islands. In 2001, a citizens advisory committee was established to work closely with the Alaska Department of Fish and Game (ADF&G), with the cooperation of Kodiak NWR, to develop a management plan addressing several problems that affect bears, including hunting, habitat, and viewing. The resulting Kodiak Archipelago Bear Conservation and Management Plan was crafted over several months by representatives from 12 diverse user groups, which, after hearing from
11375-485: The late 1880s and canneries proliferated throughout the archipelago. Bears were viewed as competitors for the salmon resource and were routinely shot when seen on streams or coasts. At the same time, sportsmen and scientists had recognized the Kodiak bear as the largest in the world, and they voiced concerns about overharvesting the population. Professional interest in guided Kodiak bear hunts and concern for unregulated resource use in frontier lands such as Alaska prompted
11500-723: 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
11625-464: The least when they emerge from their dens in the spring, and can increase their weight by 20–30% during late summer and fall. As with other animals, captive Kodiak bears can sometimes weigh considerably more than their wild counterparts. An average adult male measures 244 cm (8 ft 0 in) in length, and stands 133 cm (4 ft 4 in) tall at the shoulder. The largest recorded wild male weighed 751 kg (1,656 lb), and had
11750-463: The level of homozygosity rises in the entire collection of gamodemes. The overall rise in homozygosity is quantified by the inbreeding coefficient (f or φ). All homozygotes are increased in frequency – both the deleterious and the desirable. The mean phenotype of the gamodemes collection is lower than that of the panmictic original – which is known as inbreeding depression. It is most important to note, however, that some dispersion lines will be superior to
11875-415: The local population as well as increased hunting of Kodiak bears. Bear safety precautions aim at avoiding such situations, understanding bear needs and behavior, and learning how to recognize the warning signs bears give when stressed. One fatal bear attack on a person on the Kodiak archipelago occurred in 1999. The National Geographic Society filmed a television program about brown bears, which included
12000-470: 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
12125-504: The northeastern part of Kodiak Island. About half of the archipelago is included in the Kodiak National Wildlife Refuge . Bears live throughout the archipelago, adapting to local resources and retaining relatively small home ranges and comparable densities in most habitats. With such a variety and abundance of food sources, bears are surprisingly intelligent in their eating habits. The first foods bears eat in
12250-413: The northern islands, to steep, glaciated mountains rising to Koniag Peak's 1,360 m (4,470 ft) along the central spine of Kodiak Island, to rolling hills and flat tundra on the south end of the archipelago. About 14,000 people live on the archipelago, primarily in and around the city of Kodiak and six outlying villages. Roads and other human alterations are generally limited to Afognak Island and
12375-615: 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 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
12500-418: The panmictic original, while some will be about the same, and some will be inferior. The probabilities of each can be estimated from those binomial equations. In plant and animal breeding , procedures have been developed which deliberately utilize the effects of dispersion (such as line breeding, pure-line breeding, backcrossing). Dispersion-assisted selection leads to the greatest genetic advance (ΔG=change in
12625-500: The past decade, the population has been slowly increasing. Bears on Kodiak are naturally active during the day , but when faced with competition for food or space, they adopt a more nocturnal (active at night) lifestyle. This behavior is especially evident in the bears that live near and within Kodiak City. Kodiak bears do not defend territories, but they do have traditional areas that they use each year (home ranges). Because of
12750-771: The phenotypic mean), and is much more powerful than selection acting without attendant dispersion. This is so for both allogamous (random fertilization) and autogamous (self-fertilization) gamodemes. According to the UN, the world's population surpassed 8 billion on 15 November 2022, an increase of 1 billion since 12 March 2012. According to a separate estimate by the United Nations, Earth's population exceeded seven billion in October 2011. According to UNFPA , growth to such an extent offers unprecedented challenges and opportunities to all of humanity. According to papers published by
12875-471: The population of a certain species in a certain area can be estimated using the Lincoln index to calculate the total population of an area based on the number of individuals observed. In genetics, a population is often defined as a set of organisms in which any pair of members can breed together. They can thus routinely exchange gametes in order to have usually fertile progeny, and such a breeding group
13000-519: 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
13125-471: The rich variety of foods available on Kodiak, the bears on the archipelago have some of the smallest home ranges of any brown bear populations in North America and a great deal of overlap occurs among the ranges of individual bears. Home ranges of adult sows on Kodiak Island average 130 km (50 sq mi), while boar home ranges average 250 km (97 sq mi). Kodiak bears begin entering their dens in late October. Pregnant sows are usually
13250-410: The same geographical area and are capable of interbreeding . The area of a sexual population is the area where interbreeding is possible between any opposite-sex pair within the area and more probable than cross-breeding with individuals from other areas. In humans , interbreeding is unrestricted by racial differences, as all humans belong to the same species of Homo sapiens. In ecology,
13375-548: The same ranges and potential solutions included poisons, fences to isolate cattle ranges, and aerial shooting of bears. Again, sport hunters voiced their support for Kodiak bears. Despite public pressure, the state continued actively pursuing and dispatching problem bears until 1970. In 1971, the Alaska Native Claims Settlement Act (ANCSA) resolved many long-standing land issues with Aboriginal Alaskans statewide. The impacts were felt strongly on
13500-565: 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 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
13625-420: The size of bears is by measuring their skulls . Most North American hunting organizations and management agencies use calipers to measure the length of the skull (back of sagittal crest on the back of the skull to the front tooth), and the width (maximum width between the zygomatic arches — "cheek bones"). The total skull size is the sum of these two measurements. The largest bear ever killed in North America
13750-486: The spring are emerging vegetation (such as grasses and forbs) and animals that may have died during the winter. This allows the bear to quickly replace the weight that was lost during hibernation. As summer progresses, a wide variety of vegetation supplies nutritional needs until salmon return. Salmon runs extend from May through September on most of the archipelago and bears consume the five species of Pacific salmon that spawn in local streams and lakes. Bears often prioritize
13875-770: 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
14000-408: The state's wildlife. The Alaska Board of Game reduced bear-hunting seasons on Afognak and Raspberry Islands and on the Kodiak National Wildlife Refuge, but liberalized bear seasons on nonrefuge lands on Kodiak. During the 1960s, state biologists worked with ranchers along the Kodiak road system to examine and reduce the predation problem. Biologists reported that cattle and bears were not compatible on
14125-1257: 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 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
14250-511: The territorial government's newly established Alaska Game Commission to abolish commercial bear hunting (selling the hides) on the archipelago in 1925. The impacts of the new regulations seemed to restore bear populations on the Kodiak Islands. By the 1930s, ranchers in northeast Kodiak reported an increase in bear problems and demanded action. Bears were wrongly seen as a threat to the expanding commercial salmon-fishing industry. To address
14375-568: 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
14500-508: 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 ,
14625-403: The upcoming winter. Consequently, unmanaged bear viewing could affect several bears, especially productive sows with cubs. Often, bear-viewing and bear-hunting are considered incompatible. Even if the bear population is healthy and bear hunting is sustainable, ethical questions arise especially if hunting occurs near viewing areas and either during or soon after the viewing season. Many feel that it
14750-503: The wild was 27 years old, and the oldest female was 35. The islands of the Kodiak Archipelago have a subpolar oceanic climate with cool temperatures, overcast skies, fog, windy conditions, and moderate to heavy precipitation throughout most of the year. Although the archipelago only covers about 13,000 km (5,000 sq mi), a rich variety of topography and vegetation ranges from dense forests of Sitka spruce on
14875-570: 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
15000-431: The year. When eating deer , mountain goats , elk , or cattle, internal organs are eaten first for their high-fat content, however even though there is an abundance of the animals found on the archipelago, few Kodiak bears actively prey on them as other methods of finding food are more energy efficient. Another food source available year-round is the garbage made by the human population of Kodiak Island. The Kodiak bear
15125-401: 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
15250-479: Was from Kodiak Island, with a total skull size of 78.1 cm (30.7 in), and eight of the top 10 brown bears listed in the Boone and Crockett record book are from Kodiak. The average skull size of Kodiak bears that were killed by hunters in the first five years of the 21st century was 63.8 cm (25.1 in) for boars, and 55.4 cm (21.8 in) for sows. Also, an individual named Teddy, which portrayed
15375-484: 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
15500-526: Was the first significant invasion of inland bear habitat on Kodiak Island. To address the opposition encountered from the public and agencies, a mitigation settlement was negotiated in 1981 which included brown bear research and the establishment of the Kodiak Brown Bear Trust. The hydroelectric project was completed in 1985. Human alteration of bear habitat on Kodiak and Afognak Islands spurred renewed interest and funding for bear research on
15625-478: Was unable to determine whether it was a large American black bear or a grizzly bear. Population Population is the term typically used to refer to the number of people in a single area. Governments conduct a census to quantify the size of a resident population within a given jurisdiction. The term is also applied to non-human animals , microorganisms , and plants , and has specific uses within such fields as ecology and genetics . The word population
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