The brown bear is a large bear native to Eurasia and North America. It is one of the largest land carnivorans, rivaled in size only by its closest relative, the polar bear, which is much less variable in size and slightly bigger on average. The brown bear is a sexually dimorphic species, as adult males average around 30% larger in most populations. Brown bears are often not fully brown; the pelage can be reddish to yellowish-brown, and dark brown to cream in color. They are the only extant bears with a hump formed entirely of muscle on their shoulders. The paws are large and allow the bear to effectively dig through dirt. Its teeth are similar to those of other bears and reflect its dietary plasticity.
The American black bear, also known as the black bear, is a species of medium-sized bear endemic to North America. It is the continent's smallest and most widely distributed bear species. The American black bear is an omnivore, with a diet varying greatly depending on season and location. It typically lives in largely forested areas but will leave forests in search of food and is sometimes attracted to human communities due to the immediate availability of food.
The sloth bear, also known as the Indian bear, is a myrmecophagous bear species native to the Indian subcontinent. It feeds on fruits, ants and termites. It is listed as vulnerable on the IUCN Red List, mainly because of habitat loss and degradation. It is the only species in the genus Melursus.
The California grizzly bear, also known as the California golden bear, is an extinct population of the brown bear, generally known as the grizzly bear. "Grizzly" could have meant "grizzled" – that is, with golden and grey tips of the hair – or "fear-inspiring". Nonetheless, after careful study, naturalist George Ord formally classified it in 1815 – not for its hair, but for its character – as Ursus horribilis. Genetically, North American brown bears are closely related; in size and coloring, the California grizzly bear was much like the Kodiak bear of the southern coast of Alaska. The grizzly became a symbol of the Bear Flag Republic, a moniker that was attached to the short-lived attempt by a group of U.S. settlers to break away from Mexico in 1846. Later, this rebel flag became the basis for the state flag of California, and then California was known as the "Bear State".
The Kodiak bear, also known as the Kodiak brown bear, 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 a population of grizzly bears.
The Atlas bear or North African bear was a population of brown bear native to North Africa that became extinct in historical times.
The Eurasian brown bear is one of the most common subspecies of the brown bear, and is found in much of Eurasia. It is also called the European brown bear, common brown bear, common bear, and colloquially by many other names. The genetic diversity of present-day brown bears has been extensively studied over the years and appears to be geographically structured into five main clades based upon analysis of the mtDNA.
The Syrian brown bear is a medium-sized and endangered subspecies of Eurasian brown bear native to the Middle East and West-Central Asia, particularly around the Caucasus Mountains.
The Himalayan brown bear, also known as the Himalayan red bear or isabelline bear, is a subspecies of the brown bear occurring in the western Himalayas. It is the largest mammal in the region, males reaching up to 2.2 m long, while females are a little smaller. It is omnivorous and hibernates in dens during the winter.
The Gobi bear, known in Mongolian as the Mazaalai (Мазаалай), is a subspecies of the brown bear that is found in the Gobi Desert of Mongolia. It is listed as critically endangered by the Mongolian Redbook of Endangered Species and by IUCN standards. Currently, there are only 31 bears left in the Mongolian Gobi Desert; through long-term genetic monitoring it is known that the population is relatively stable, however, the sex ratio is highly skewed towards males. Gobi bears are separated by enough distance from other brown bear populations to achieve reproductive isolation. In 1959, hunting of the animal was prohibited in order to preserve the dying subspecies.
The Kamchatka brown bear, also known as the Far Eastern brown bear, or in Russian: камчатский бурый медведь, romanized: kamchatsky bury medved, is a subspecies of brown bear native to the Russian Kamchatka Peninsula.
The Cantabrian brown bear, Iberian brown bear, or Iberian bear is a population of Eurasian brown bears living in the Cantabrian Mountains of Spain.
The Ussuri brown bear, also known as the Ezo brown bear, Russian grizzly bear, or the black grizzly bear, is a subspecies of the brown bear or a population of the Eurasian brown bear. One of the largest brown bears, a very large Ussuri brown bear may approach the Kodiak bear in size. It is not to be confused with the North American grizzly bear.
The grizzly bear, also known as the North American brown bear or simply grizzly, is a population or subspecies of the brown bear inhabiting North America.
The Alaska Peninsula brown bear or "peninsular grizzly" is a colloquial nomenclature for a possible brown bear subspecies that lives in the coastal regions of southern Alaska. It may be a population of the mainland grizzly bear subspecies.
The ABC Islands bear or Sitka brown bear is a subspecies or population of brown bear that resides in Southeast Alaska and is found on Admiralty Island, Baranof Island, and Chichagof Island in Alaska, and a part of the Alexander Archipelago. It has a unique genetic structure that relates them not only to brown bears, but also to polar bears. Its habitat exists within the Tongass National Forest, which is part of the perhumid rainforest zone.
The steppe brown bear is a disputed extinct subspecies of brown bear that lived in Eurasia during either the Pleistocene or the early Holocene epochs, but its geological age is uncertain. Fossils of the bear have been found in various caves in Slovakia, particularly those of Vazec, Vyvieranie, Lisková, Kupcovie Izbicka, and Okno. It is argued that the subspecies should be rendered invalid, as its geological age is unclear and "its skull is identical to modern U. arctos."
Formerly or currently considered subspecies or populations of brown bears have been listed as follows:
The brown bear is one of the most omnivorous animals in the world and has been recorded to consume the greatest variety of foods of any bear. Throughout life, this species is regularly curious about the potential of eating virtually any organism or object that they encounter. Certainly no other animal in their given ecosystems, short perhaps of other bear species and humans, can claim to feed on as broad a range of dietary opportunities. Food that is both abundant and easily obtained is preferred. Their jaw structure has evolved to fit their dietary habits. Their diet varies enormously throughout their differing areas based on opportunity. In spring, winter-provided carrion, grasses, shoots, sedges and forbs are the dietary mainstays for brown bears from almost every part of their distribution. Fruits, including berries, become increasingly important during summer and early autumn. Roots and bulbs become critical in autumn for some inland bear populations if fruit crops are poor. The dietary variability is illustrated in the western United States, as meat made up 51% of the average year-around diet for grizzly bears from Yellowstone National Park, while it made up only 11% of the year-around diet for grizzlies from Glacier National Park a few hundred miles to the north.
