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Armstrong Reef
Armstrong Reef is a reef that encompasses many ice-free plutonic islets and rocks, extending for from the south-west end of Renaud Island, in the Biscoe Islands of Antarctica. It was first accurately shown on an Argentine government chart of 1957, and was named by the UK Antarctic Place-Names Committee for Terence Armstrong, a British sea ice specialist. Important Bird Area The reef has been identified as a 557 ha Important Bird Area by BirdLife International because it supports a breeding colony of over 500 pairs of Antarctic shag The Antarctic shag (''Leucocarbo bransfieldensis''), sometimes referred to as the imperial cormorant, king cormorant, imperial shag, blue-eyed shag or Antarctic cormorant, is the only species of the cormorant family found in the Antarctic. It is s ...s. References Reefs of Graham Land Landforms of the Biscoe Islands Important Bird Areas of Antarctica Seabird colonies {{Biscoes-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reef
A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock outcrops, etc.—but there are also reefs such as the coral reefs of tropical waters formed by biotic processes dominated by corals and coralline algae, and artificial reefs such as shipwrecks and other anthropogenic underwater structures may occur intentionally or as the result of an accident, and sometimes have a designed role in enhancing the physical complexity of featureless sand bottoms, to attract a more diverse assemblage of organisms. Reefs are often quite near to the surface, but not all definitions require this. Earth's largest coral reef system is the Great Barrier Reef in Australia, at a length of over . Biotic There is a variety of biotic reef types, including oyster reefs and sponge reefs, but the most massive and widely ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pluton
In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and compositions, illustrated by examples like the Palisades Sill of New York and New Jersey; the Henry Mountains of Utah; the Bushveld Igneous Complex of South Africa; Shiprock in New Mexico; the Ardnamurchan intrusion in Scotland; and the Sierra Nevada Batholith of California. Because the solid country rock into which magma intrudes is an excellent insulator, cooling of the magma is extremely slow, and intrusive igneous rock is coarse-grained (phaneritic). Intrusive igneous rocks are classified separately from extrusive igneous rocks, generally on the basis of their mineral content. The relative amounts of quartz, alkali feldspar, plagioclase, and feldspathoid is particularly important in classifying intrusive igneous rocks. Intrusions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Renaud Island
Renaud Island is an ice-covered island in the Biscoe Islands of Antarctica, long and from (average ) wide, lying between the Pitt Islands and Rabot Island. It is separated from the Pitt Islands to the northeast by Mraka Sound, and from Lavoisier Island to the southwest by Pendleton Strait. History The Biscoe Islands were discovered in 1832 by a British expedition under John Biscoe and were first roughly surveyed by the French Antarctic Expedition under Jean-Baptiste Charcot, 1903–05 and 1908–10. It was on this second expedition that Renaud Island was first charted and named. Renaud Island was again roughly surveyed in 1935-36 by the British Graham Land Expedition (BGLE). A number of the island's geographical features have been individually charted and named. The majority, except where noted below, were first accurately charted on an Argentine government chart of 1957, and named by the United Kingdom Antarctic Place-Names Committee (UK-APC) during the 1950s. Geography ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biscoe Islands
Biscoe Islands is a series of islands, of which the principal ones are Renaud, Lavoisier (named ''Serrano'' by Chile and ''Mitre'' by Argentina), Watkins, Krogh, Pickwick and Rabot, lying parallel to the west coast of Graham Land and extending between Southwind Passage on the northeast and Matha Strait on the southwest. Another group of islands are the Adolph Islands. The islands are named for John Biscoe, the commander of a British expedition which explored the islands in February 1832. See also * Bates Island * Composite Antarctic Gazetteer * List of Antarctic islands south of 60° S * SCAR * Southwind Passage * Territorial claims in Antarctica Seven sovereign states – Argentina, Australia, Chile, France, New Zealand, Norway, and the United Kingdom – have made eight territorial claims in Antarctica. These countries have tended to place their Antarctic scientific observation and st ... References * Archipelagoes of the Southern Ocean Islands of Antarct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost . Antarctica holds the record for the lowest measured temperature on Earth, . The coastal regions can reach temperatures over in summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where vegetation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argentine
Argentines (mistakenly translated Argentineans in the past; in Spanish (masculine) or (feminine)) are people identified with the country of Argentina. This connection may be residential, legal, historical or cultural. For most Argentines, several (or all) of these connections exist and are collectively the source of their being ''Argentine''. Argentina is a multiethnic and multilingual society, home to people of various ethnic, religious, and national origins, with the majority of the population made up of Old World immigrants and their descendants. As a result, Argentines do not equate their nationality with ethnicity, but with citizenship and allegiance to Argentina. Aside from the indigenous population, nearly all Argentines or their ancestors immigrated within the past five centuries. Among countries in the world that have received the most immigrants in modern history, Argentina, with 6.6 million, ranks second to the United States (27 million), and ahead of other immigr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UK Antarctic Place-Names Committee
The UK Antarctic Place-Names Committee (or UK-APC) is a United Kingdom government committee, part of the Foreign and Commonwealth Office, responsible for recommending names of geographical locations within the British Antarctic Territory (BAT) and the South Georgia and the South Sandwich Islands (SGSSI). Such names are formally approved by the Commissioners of the BAT and SGSSI respectively, and published in the BAT Gazetteer and the SGSSI Gazetteer maintained by the Committee. The BAT names are also published in the international Composite Gazetteer of Antarctica maintained by Scientific Committee on Antarctic Research, SCAR. The Committee may also consider proposals for new place names for geographical features in areas of Antarctica outside BAT and SGSSI, which are referred to other Antarctic place-naming authorities, or decided by the Committee itself if situated in the unclaimed sector of Antarctica. Names attributed by the committee * Anvil Crag, named for descriptive featu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Ice
Sea ice arises as seawater freezes. Because ice is less dense than water, it floats on the ocean's surface (as does fresh water ice, which has an even lower density). Sea ice covers about 7% of the Earth's surface and about 12% of the world's oceans. Much of the world's sea ice is enclosed within the polar ice packs in the Earth's polar regions: the Arctic ice pack of the Arctic Ocean and the Antarctic ice pack of the Southern Ocean. Polar packs undergo a significant yearly cycling in surface extent, a natural process upon which depends the Arctic ecology, including the ocean's ecosystems. Due to the action of winds, currents and temperature fluctuations, sea ice is very dynamic, leading to a wide variety of ice types and features. Sea ice may be contrasted with icebergs, which are chunks of ice shelves or glaciers that calve into the ocean. Depending on location, sea ice expanses may also incorporate icebergs. General features and dynamics Sea ice does not simply grow and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Important Bird Area
An Important Bird and Biodiversity Area (IBA) is an area identified using an internationally agreed set of criteria as being globally important for the conservation of bird populations. IBA was developed and sites are identified by BirdLife International. There are over 13,000 IBAs worldwide. These sites are small enough to be entirely conserved and differ in their character, habitat or ornithological importance from the surrounding habitat. In the United States the Program is administered by the National Audubon Society. Often IBAs form part of a country's existing protected area network, and so are protected under national legislation. Legal recognition and protection of IBAs that are not within existing protected areas varies within different countries. Some countries have a National IBA Conservation Strategy, whereas in others protection is completely lacking. History In 1985, following a specific request from the European Economic Community, Birdlife International ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BirdLife International
BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding important sites for birds, maintaining and restoring key bird habitats, and empowering conservationists worldwide. It has a membership of more than 2.5 million people across 116 country partner organizations, including the Royal Society for the Protection of Birds, the Wild Bird Society of Japan, the National Audubon Society and American Bird Conservancy. BirdLife International has identified 13,000 Important Bird and Biodiversity Areas and is the official International Union for Conservation of Nature’s Red List authority for birds. As of 2015, BirdLife International has established that 1,375 bird species (13% of the total) are threatened with extinction ( critically endangered, endangered or vulnerable). BirdLife International p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Colony
A bird colony is a large congregation of individuals of one or more species of bird that nest or roost in proximity at a particular location. Many kinds of birds are known to congregate in groups of varying size; a congregation of nesting birds is called a breeding colony. Colonial nesting birds include seabirds such as auks and albatrosses; wetland species such as herons; and a few passerines such as weaverbirds, certain blackbirds, and some swallows. A group of birds congregating for rest is called a communal roost. Evidence of colonial nesting has been found in non- neornithine birds ( Enantiornithes), in sediments from the Late Cretaceous (Maastrichtian) of Romania. Variations on colonial nesting in birds Approximately 13% of all bird species nest colonially. Nesting colonies are very common among seabirds on cliffs and islands. Nearly 95% of seabirds are colonial, leading to the usage, seabird colony, sometimes called a rookery. Many species of terns nest in colonie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctic Shag
The Antarctic shag (''Leucocarbo bransfieldensis''), sometimes referred to as the imperial cormorant, king cormorant, imperial shag, blue-eyed shag or Antarctic cormorant, is the only species of the cormorant family found in the Antarctic. It is sometimes considered conspecific with the Imperial shag (''Leucocarbo atriceps''). Description The adult Antarctic shag is about 75–77 cm tall, has a wingspan of 124 cm, and weighs 1.5-3.5 kg. When looking at individuals within this species, the most defining characteristic is the warty yellow caruncle found on the forehead. Additionally, the blue "eye", which is actually blue skin surrounding the eye, is a distinct trait that stands out. The head, wings, and outside of the thighs are black. While the underparts and central back are white. White is also found on the wing bars that line the upper wing. The bill is dark ranging from brown to yellow. As the bill hooks, the lower mandible becomes lighter. The species has nak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
