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Colville Delta
Colville Delta is a river delta in northern Alaska that flows into Harrison Bay. The delta is so flat that it has been said that it is indiscernible where the river ends and the ocean begins. The powerful outflow of the Colville River creates a shallow region that is rich with nutrients, making it ecologically significant for wildlife. Geography The Colville River, approximately long, flows from the De Long Mountains until it reaches the Alaska Native community of Nuiqsut, where it forms a broad delta. Fauna The waters of the Colville delta, along with the waters of Harrison Bay, make an ideal refuge for long-tailed ducks, king eiders, red-throated loons, Arctic terns, surf scoters, brant geese, and glaucous gulls. In summer and fall, migrating red-throated and yellow-billed loons and king and spectacled eiders stop in to rest and feed. Nearshore forage fish are important in Arctic food webs, linking energy from smaller prey items to larger predators like birds and marine mamm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harrison Bay (Beaufort Sea)
Harrison Bay is an estuary located north of Alaska that opens into the Beaufort Sea. It is adjacent to the Colville Delta. The powerful outflow of the Colville River creates a shallow region that is rich with nutrients, making it ecologically significant for wildlife. Geography Harrison Bay is bordered by Cape Halkett near Teshekpuk Lake on the western side and Oliktok Point on the eastern side. From Oliktok Point, a long chain of barrier islands head east and cross through Prudhoe Bay. Fauna The waters of Harrison Bay make an ideal refuge for long-tailed ducks, king eiders, red-throated loons, Arctic terns, surf scoters, brant geese, and glaucous gulls. In summer and fall, migrating red-throated and yellow-billed loons and king and spectacled eiders stop in to rest and feed. Nearshore forage fish are important in Arctic food webs, linking energy from smaller prey items to larger predators like birds and marine mammals. Harrison Bay is important habitat for forage fish, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River Delta
A river delta is a landform shaped like a triangle, created by deposition of sediment that is carried by a river and enters slower-moving or stagnant water. This occurs where a river enters an ocean, sea, estuary, lake, reservoir, or (more rarely) another river that cannot carry away the supplied sediment. It is so named because its triangle shape resembles the Greek letter Delta. The size and shape of a delta is controlled by the balance between watershed processes that supply sediment, and receiving basin processes that redistribute, sequester, and export that sediment. The size, geometry, and location of the receiving basin also plays an important role in delta evolution. River deltas are important in human civilization, as they are major agricultural production centers and population centers. They can provide coastline defense and can impact drinking water supply. They are also ecologically important, with different species' assemblages depending on their landscape posi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capelin
The capelin or caplin (''Mallotus villosus'') is a small forage fish of the smelt family found in the North Atlantic, North Pacific and Arctic oceans. In summer, it grazes on dense swarms of plankton at the edge of the ice shelf. Larger capelin also eat a great deal of krill and other crustaceans. Among others, whales, seals, Atlantic cod, Atlantic mackerel, squid and seabirds prey on capelin, in particular during the spawning season while the capelin migrate south. Capelin spawn on sand and gravel bottoms or sandy beaches at the age of two to six years. When spawning on beaches, capelin have an extremely high post-spawning mortality rate which, for males, is close to 100%. Males reach in length, while females are up to long. They are olive-coloured dorsally, shading to silver on sides. Males have a translucent ridge on both sides of their bodies. The ventral aspects of the males iridesce reddish at the time of spawn. Capelin migration Capelin populations in the Barents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Cod
''Arctogadus glacialis'', known also with ambiguous common names Arctic cod and polar cod, is an Arctic species of fish in the cod family Gadidae, related to the true cod (genus ''Gadus''). ''Arctogadus glacialis'' is found in icy water. They grow to about 30 cm long, and are favorite food of narwhals and other arctic whales. Common names and taxonomy The common names "Arctic cod" and "polar cod" can refer to either ''Arctogadus glacialis'' or '' Boreogadus saida'', and "Arctic cod" may also refer to ''Eleginus nawaga''. Another Arctic gadid, the East Siberian cod (''Arctogadus borisovi''), was until recently considered the closest relative of ''A. glacialis''. It has, however, been found not to be distinct from ''A. glacialis'', and should be included in this species. According to this result, ''Arctogadus'' is a monotypic genus. However, ''Arctogadus'' is a close relative of '' Boreogadus'', and should perhaps be included in that genus. Appearance Arctic cod have bee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broad Whitefish
The broad whitefish (''Coregonus nasus'') is a freshwater whitefish species. Dark silvery in colour, and like a herring in its shape, its distinctive features include a convex head, short gill rakers, and a mild overbite. It is found in the Arctic-draining streams, lakes, and rivers of far eastern Russia and North America. Its prey includes larval insects, snails, and shellfish. It is eaten by humans and brown bears. Description The broad whitefish is a herring-shaped fish with a more compressed body and convex head than other whitefishes. It is iridescent, with a dark olive-brown back, silvery grey sides, and a whitish bottom.Froese and Pauly, 2010 Features that distinguish it from other species include a mild overbite and 18–25 short gill rakers. The fins of adults are grey, while those of young fish are grey.Alaska Natural Heritage Program, 2005 It reaches a maximum length of , and a maximum weight of . Distribution and habitat The broad whitefish is found in Arctic-dr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salmonidae
Salmonidae is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes . It includes salmon (both Atlantic and Pacific species), trout (both ocean-going and landlocked), chars, freshwater whitefishes, graylings, taimens and lenoks, which are collectively known as the salmonids ("salmon-like fish"). The Atlantic salmon (''Salmo salar''), whose Latin name became that of its genus '' Salmo'', is also the source of the family and order names. Salmonids have a relatively primitive appearance among the teleost fish, with the pelvic fins being placed far back, and an adipose fin towards the rear of the back. They have slender bodies, with rounded scales and forked tails, and their mouths contain a single row of sharp teeth. Although the smallest species is just long as an adult, most are much larger, with the largest reaching . All salmonids spawn in fresh water of upper reaches of rivers and creeks, but in many cases, the fish spend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Cisco
Arctic cisco (''Coregonus autumnalis''), also known as omul russian: Омуль, is an anadromous species of freshwater whitefish that inhabits the Arctic parts of Siberia, Alaska and Canada. It has a close freshwater relative in several lakes of Ireland, known as the pollan, alternatively regarded as conspecific with it, or as a distinct species. Taxonomy The freshwater omul of Lake Baikal, formerly considered a subspecies ''Coregonus autumnalis migratorius'' of the Arctic cisco, has no close genetic relationship to it and is now classified as a separate species, ''Coregonus migratorius''. Description The Arctic cisco have a relatively small head with a non-prominent snout. They have metallic silver body, a brown or dark green back, and nearly colorless fins. They have neither spots nor teeth on their jaws. They do have a patch of teeth on their tongue. They can reach 50 cm (20 in) in length and can weight up to 2 kg (4.4 lbs), but are usually less than 40 cm (16 in) in le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forage Fish
Forage fish, also called prey fish or bait fish, are small pelagic fish which are preyed on by larger predators for food. Predators include other larger fish, seabirds and marine mammals. Typical ocean forage fish feed near the base of the food chain on plankton, often by filter feeding. They include particularly fishes of the order Clupeiformes (herrings, sardines, shad, hilsa, menhaden, anchovies, and sprats), but also other small fish, including halfbeaks, silversides, smelt such as capelin and goldband fusiliers. Forage fish compensate for their small size by forming schools. Some swim in synchronised grids with their mouths open so they can efficiently filter plankton. These schools can become immense shoals which move along coastlines and migrate across open oceans. The shoals are concentrated energy resources for the great marine predators. The predators are keenly focused on the shoals, acutely aware of their numbers and whereabouts, and make migrations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glaucous Gull
The glaucous gull (''Larus hyperboreus'') is a large gull, the second-largest gull in the world. It breeds in Arctic regions of the Northern Hemisphere and winters south to shores of the Holarctic. The genus name is from Latin ''larus'', which appears to have referred to a gull or other large seabird. The specific name ''hyperboreus'' is Latin for "northern" from the Ancient Greek ''Huperboreoi'' people from the far north " Glaucous" is from Latin ''glaucus'' and denotes the grey colour of the gull. An older English name for this species is burgomaster. This gull is migratory, wintering from in the North Atlantic and North Pacific Oceans as far south as the British Isles and northernmost states of the United States, also on the Great Lakes. A few birds sometimes reach the southern USA and northern Mexico. Description This is a large and powerful gull, second-largest of all gull species and very pale in all plumage, with no black on either the wings or the tail. Adults are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brant (goose)
The brant or brent goose (''Branta bernicla'') is a small goose of the genus ''Branta''. There are three subspecies, all of which winter along temperate-zone sea-coasts and breed on the high-Arctic tundra. The Brent oilfield was named after the species. Description The brant is a small goose with a short, stubby bill. It measures long, across the wings and weighs . The under-tail is pure white, and the tail black and very short (the shortest of any goose). The species is divided into three subspecies: * Dark-bellied brant goose ''B. b. bernicla'' (Linnaeus, 1758) * Pale-bellied brant goose ''B. b. hrota'' (Müller, 1776) (also known as light-bellied brent goose in Europe, and Atlantic brant in North America) * Black brant goose ''B. b. nigricans'' ( Lawrence, 1846) (sometimes also known as the Pacific brant in North America) Some DNA evidence suggests that these forms are genetically distinct; while a split into three separate species has been proposed, it is not widel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surf Scoter
The surf scoter (''Melanitta perspicillata'') is a large sea duck native to North America. Adult males are almost entirely black with characteristic white patches on the forehead and the nape and adult females are slightly smaller and browner. Surf scoters breed in Northern Canada and Alaska and winter along the Pacific and Atlantic coasts of North America. Those diving ducks mainly feed on benthic invertebrates, mussels representing an important part of their diet. Taxonomy In 1750 the English naturalist George Edwards included an illustration and a description of the surf scoter in the third volume of his ''A Natural History of Uncommon Birds''. He used the English name "The great black duck from Hudson's Bay". Edwards based his hand-coloured etching on a preserved specimen that had been brought to London from the Hudson Bay area of Canada by James Isham. When in 1758 the Swedish naturalist Carl Linnaeus updated his ''Systema Naturae'' for the tenth edition, he placed the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Tern
The Arctic tern (''Sterna paradisaea'') is a tern in the family Laridae. This bird has a circumpolar breeding distribution covering the Arctic and sub-Arctic regions of Europe (as far south as Brittany), Asia, and North America (as far south as Massachusetts). The species is strongly migratory, seeing two summers each year as it migrates along a convoluted route from its northern breeding grounds to the Antarctic coast for the southern summer and back again about six months later. Recent studies have shown average annual round-trip lengths of about for birds nesting in Iceland and Greenland and about for birds nesting in the Netherlands. These are by far the longest migrations known in the animal kingdom. The Arctic tern nests once every one to three years (depending on its mating cycle). Arctic terns are medium-sized birds. They have a length of and a wingspan of . They are mainly grey and white plumaged, with a red/orange beak and feet, white forehead, a bla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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