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 polar bear is a large bear native to the Arctic and nearby areas. It is closely related to the brown bear, and the two species can interbreed. The polar bear is the largest extant species of bear and land carnivore, with adult males weighing 300–800 kg (660–1,760 lb). The species is sexually dimorphic, as adult females are much smaller. The polar bear is white- or yellowish-furred with black skin and a thick layer of fat. It is more slender than the brown bear, with a narrower skull, longer neck and lower shoulder hump. Its teeth are sharper and more adapted to cutting meat. The paws are large and allow the bear to walk on ice and paddle in the water.
The walrus is a large pinniped marine mammal with discontinuous distribution about the North Pole in the Arctic Ocean and subarctic seas of the Northern Hemisphere. It is the only extant species in the family Odobenidae and genus Odobenus. This species is subdivided into two subspecies: the Atlantic walrus, which lives in the Atlantic Ocean, and the Pacific walrus, which lives in the Pacific Ocean.
The cave bear is a prehistoric species of bear that lived in Europe and Asia during the Pleistocene and became extinct about 24,000 years ago during the Last Glacial Maximum.
The ringed seal is an earless seal inhabiting the Arctic and sub-Arctic regions. The ringed seal is a relatively small seal, rarely greater than 1.5 m in length, with a distinctive patterning of dark spots surrounded by light gray rings, hence its common name. It is the most abundant and wide-ranging ice seal in the Northern Hemisphere, ranging throughout the Arctic Ocean, into the Bering Sea and Okhotsk Sea as far south as the northern coast of Japan in the Pacific and throughout the North Atlantic coasts of Greenland and Scandinavia as far south as Newfoundland, and including two freshwater subspecies in northern Europe. Ringed seals are one of the primary prey of polar bears and killer whales, and have long been a component of the diet of indigenous people of the Arctic.
The dark-eyed junco is a species of junco, a group of small, grayish New World sparrows. The species is common across much of temperate North America and in summer it ranges far into the Arctic. It is a variable species, much like the related fox sparrow, and its systematics are still not completely resolved.
The Arctic wolf, also known as the white wolf, polar wolf, and the Arctic grey wolf, is a subspecies of grey wolf native to the High Arctic tundra of Canada's Queen Elizabeth Islands, from Melville Island to Ellesmere Island. Unlike some populations that move between tundra and forest regions, Arctic wolves spend their entire lives north of the northern treeline. Their distribution to south is limited to the northern fringes of the Middle Arctic tundra on the southern half of Prince of Wales and Somerset Islands. It is a medium-sized subspecies, distinguished from the northwestern wolf by its smaller size, its whiter colouration, its narrower braincase, and larger carnassials. Since 1930, there has been a progressive reduction in size in Arctic wolf skulls, which is likely the result of wolf-dog hybridization.
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 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.
An ursid hybrid is an animal with parents from two different species or subspecies of the bear family (Ursidae). Species and subspecies of bear known to have produced offspring with another bear species or subspecies include American black bears, grizzly bears, and polar bears, all of which are members of the genus Ursus. Bears not included in Ursus, such as the giant panda, are expected to be unable to produce hybrids with other bears. The giant panda bear belongs to the genus Ailuropoda.
A grizzly-polar-bear-hybrid is a rare ursid hybrid that has occurred both in captivity and in the wild. In 2006, the occurrence of this hybrid in nature was confirmed by testing the DNA of a unique-looking bear who had been shot near Sachs Harbour, Northwest Territories, on Banks Island in the Canadian Arctic. The number of confirmed hybrids has since risen to eight, all of them descending from the same female polar bear.
The Bølling–Allerød Interstadial, also called the Late Glacial Interstadial (LGI), was an interstadial period which occurred from 14,690 to c. 12,890 years Before Present, during the final stages of the Last Glacial Period. It was defined by abrupt warming in the Northern Hemisphere, and a corresponding cooling in the Southern Hemisphere, as well as a period of major ice sheet collapse and corresponding sea level rise known as Meltwater pulse 1A. This period was named after two sites in Denmark where paleoclimate evidence for it was first found, in the form of vegetation fossils that could have only survived during a comparatively warm period in Northern Europe. It is also referred to as Interstadial 1 or Dansgaard–Oeschger event 1.
The wildlife of Alaska is both diverse and abundant. The Alaskan Peninsula provides an important habitat for fish, mammals, reptiles, and birds. At the top of the food chain are the bears. Alaska contains about 70% of the total North American brown bear population and the majority of the grizzly bears, as well as black bears and Kodiak bears. In winter, polar bears can be found in the Kuskokwim Delta, St. Matthew Island, and at the southernmost portion of St. Lawrence Island. Other major mammals include moose and caribou, bison, wolves and wolverines, foxes, otters and beavers. Fish species are extensive, including: salmon, graylings, char, rainbow and lake trout, northern pike, halibut, pollock, and burbot. The bird population consists of hundreds of species, including: bald eagles, owls, falcons, ravens, ducks, geese, swans, and the passerines. Sea lions, seals, sea otters, and migratory whales are often found close to shore and in offshore waters. The Alaskan waters are home to two species of turtles, the leatherback sea turtle and the green sea turtle. Alaska has two species of frogs, the Columbia spotted frog and wood frog, plus two introduced species, the Pacific tree frog and the red-legged frog. The only species of toad in Alaska is the western toad. There are over 3,000 recorded species of marine macroinvertebrates inhabiting the marine waters, the most common being the various species of shrimp, crab, lobster, and sponge.
The Alexander Archipelago wolf, also known as the Islands wolf, is a subspecies of the gray wolf. The coastal wolves of southeast Alaska inhabit the area that includes the Alexander Archipelago, its islands, and a narrow strip of rugged coastline that is biologically isolated from the rest of North America by the Coast Mountains.
On Your Knees Cave (49-PET-408) is an archaeological site located in southeastern Alaska. Human remains were found at the site in 1996 that dated between 9,730 ±60 and 9,880±50 radiocarbon YBP or a calendrical date of 10,300 YBP. In addition to human skeletal remains, stone tools and animal bones were discovered. DNA analyses performed on the human skeletal remains document the presence of mitochondrial haplogroup D which occurs widely in the Americas. Isotopic analysis indicated that the individual had a primarily marine based diet.
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 northern and southern hemispheres of the earth have a dynamic history of advancing and retreating ice sheets. The glacial and interglacial periods are linked to regular eccentricities in the Earth's orbit and correspond to approximately 100 kyr cycles. The advancing, or glacial periods can cause a massive displacement of flora and fauna as it drives them away from the poles, with the most recent glacial maximum having occurred about 20,000 years ago.,
The Beringian wolf is an extinct population of wolf that lived during the Ice Age. It inhabited what is now modern-day Alaska, Yukon, and northern British Columbia. Some of these wolves survived well into the Holocene. The Beringian wolf is an ecomorph of the gray wolf and has been comprehensively studied using a range of scientific techniques, yielding new information on their prey species and feeding behaviors. It has been determined that these wolves are morphologically distinct from modern North American wolves and genetically basal to most modern and extinct wolves. The Beringian wolf has not been assigned a subspecies classification and its relationship with the extinct European cave wolf is not clear.
The Arctic ringed seal is a subspecies of ringed seals. Arctic ringed seals inhabit the Arctic Ocean, and are the most abundant and wide-ranging seal in the Northern Hemisphere. The ringed seal species is the smallest true seal, and gets its name from a distinctive patterning of light spots on dark grey colored fur. The ringed seal is commonly preyed upon by Polar bears, Arctic foxes, and Killer whales. Population estimates and survival rates are unknown, but average life expectancy is 15-28 years. Ringed seals have long been a component of the diet of indigenous people of the Arctic. Arctic ringed seals have been listed as threatened on the Endangered Species Act since 2012, and increasingly face loss of their habitat due to shrinking ice and snow cover.
The Haida ermine is a mustelid species endemic to a few islands off the Pacific Northwest of North America, namely Haida Gwaii in Canada and the southern Alexander Archipelago in the U.S. state of Alaska.
