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Kasatochi Island
Kasatochi Island ( ale, Qanan-tanax̂; russian: Касаточий остров), also known as Kasatochi volcano, is an active stratovolcano and part of the Andreanof Islands subgroup of the Aleutian Islands of southwestern Alaska. On 7 August 2008, Kasatochi began erupting explosively with an ash plume reaching 45,000 feet. The eruption lasted for 24 hours and destroyed most life on the island. It currently does not support any consistent human population. Kasatochi Island is a member of the Aleutian Islands, which lie above a narrow ridge that separates the Bering Sea from the North Pacific.Gary S. Drew, Donald E. Dragoo, Martin Renner and John F. Piatt Arctic, Antarctic, and Alpine Research, Vol. 42, No. 3 (August 2010), pp. 325-334 It lies at the Atka Pass northwest of the western tip of Atka Island and east of Great Sitkin Island. It is at 52.177° N latitude and 175.508° W longitude, with a summit elevation of 314 m (1030 ft.) It has a land area of 1.9503 sq ...
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Volcanic Crater Lake
A volcanic crater lake is a lake in a crater that was formed by explosive activity or a collapse during a volcanic eruption. Formation Lakes in calderas fill large craters formed by the collapse of a volcano during an eruption. Lakes in maars fill medium-sized craters where an eruption deposited debris around a vent. Crater lakes form as the created depression, within the crater rim, is filled by water. The water may come from precipitation, groundwater circulation (often hydrothermal fluids in the case of volcanic craters) or melted ice. Its level rises until an equilibrium is reached between the rates of incoming and outgoing water. Sources of water loss singly or together may include evaporation, subsurface seepage, and, in places, surface leakage or overflow when the lake level reaches the lowest point on its rim. At such a saddle location, the upper portion of the lake is contained only by its adjacent natural volcanic dam; continued leakage through or surface outflow ac ...
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Fauna
Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is '' funga''. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Greek equivalent of fauna. ''Fauna'' is also the word for a book that catalogues the animals in such a manner. The term was first used b ...
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Volcanic Ash
Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, created during volcano, volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to refer to all explosive eruption products (correctly referred to as ''tephra''), including particles larger than 2 mm. Volcanic ash is formed during explosive volcanic eruptions when dissolved gases in magma expand and escape violently into the atmosphere. The force of the gases shatters the magma and propels it into the atmosphere where it solidifies into fragments of volcanic rock and glass. Ash is also produced when magma comes into contact with water during phreatomagmatic eruptions, causing the water to explosively flash to steam leading to shattering of magma. Once in the air, ash is transported by wind up to thousands of kilometres away. Due to its wide dispersal, ash can have a number of impacts on society, including animal a ...
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Pyroclastic Flows
A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of but is capable of reaching speeds up to . The gases and tephra can reach temperatures of about . Pyroclastic flows are the most deadly of all volcanic hazards and are produced as a result of certain explosive eruptions; they normally touch the ground and hurtle downhill, or spread laterally under gravity. Their speed depends upon the density of the current, the volcanic output rate, and the gradient of the slope. Origin of term The word ''pyroclast'' is derived from the Greek (''pýr''), meaning "fire", and (''klastós''), meaning "broken in pieces". A name for pyroclastic flows which glow red in the dark is (French, "burning cloud"); this was notably used to describe the disastrous 1902 eruption of Mount Pelée on Martinique, a Frenc ...
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Adak Island
Adak Island ( ale, Adaax, russian: Адак) or Father Island is an island near the western extent of the Andreanof Islands group of the Aleutian Islands in Alaska. Alaska's southernmost town, Adak, Alaska, Adak, is located on the island. The island has a land area of , measuring long and wide, making it the List of islands of the United States by area, 25th largest island in the United States. Due to harsh winds, frequent cloud cover, and cold temperatures, vegetation is mostly tundra (grasses, mosses, berries, low-lying flowering plants) at lower elevations. The highest point is Mount Moffett, near the northwest end of the island, at an elevation of 3,924 feet (1,196 m). It is snow covered the greater part of the year. Adak is its largest and principal city. The word ''Adak'' is from the Aleut language, Aleut word ''adaq'', which means "father". History Adak Island has been the home to Aleut people, Aleut peoples since antiquity. Russian explorers in the 18th century also v ...
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Ashfall
The Ashfall Fossil Beds of Antelope County in northeastern Nebraska are rare fossil sites of the type called lagerstätten that, due to extraordinary local conditions, capture an ecological "snapshot" in time of a range of well-preserved fossilized organisms. Ash from a Yellowstone hotspot eruption 10-12 million years ago created these fossilized bone beds. The ash depth was up to 1 foot. The site is protected as Ashfall Fossil Beds State Historical Park, a park that includes a visitor center with interpretive displays and working fossil preparation laboratory, and a protected ongoing excavation site, the Hubbard Rhino Barn, featuring fossil ''Teleoceras'' (native hippo-like ancestral rhinoceros) and ancestral horses. The Ashfall Fossil Beds are especially famous for fossils of mammals from the middle Miocene geologic epoch. The Ashfall Fossil Beds are stratigraphically part of the Serravallian-age Ogallala Group. Bruneau-Jarbidge event The Ashfall deposit preserves the f ...
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Fish And Wildlife Service
The United States Fish and Wildlife Service (USFWS or FWS) is an agency within the United States Department of the Interior dedicated to the management of fish, wildlife, and natural habitats. The mission of the agency is "working with others to conserve, protect, and enhance fish, wildlife, plants and their habitats for the continuing benefit of the American people." Among the responsibilities of the USFWS are enforcing federal wildlife laws; protecting endangered species; managing migratory birds; restoring nationally significant fisheries; conserving and restoring wildlife habitats, such as wetlands; helping foreign governments in international conservation efforts; and distributing money to fish and wildlife agencies of U.S. states through the Wildlife Sport Fish and Restoration Program. The vast majority of fish and wildlife habitats are on state or private land not controlled by the United States government. Therefore, the USFWS works closely with private groups such a ...
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Pyroclastic Flows
A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of but is capable of reaching speeds up to . The gases and tephra can reach temperatures of about . Pyroclastic flows are the most deadly of all volcanic hazards and are produced as a result of certain explosive eruptions; they normally touch the ground and hurtle downhill, or spread laterally under gravity. Their speed depends upon the density of the current, the volcanic output rate, and the gradient of the slope. Origin of term The word ''pyroclast'' is derived from the Greek (''pýr''), meaning "fire", and (''klastós''), meaning "broken in pieces". A name for pyroclastic flows which glow red in the dark is (French, "burning cloud"); this was notably used to describe the disastrous 1902 eruption of Mount Pelée on Martinique, a Frenc ...
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Steller Sea Lion
The Steller sea lion (''Eumetopias jubatus''), also known as the Steller's sea lion and northern sea lion, is a near-threatened species of sea lion in the northern Pacific. It is the sole member of the genus ''Eumetopias'' and the largest of the eared seals (Otariidae). Among pinnipeds, only the walrus and the two species of elephant seals are bigger. The species is named for the naturalist Georg Wilhelm Steller, who first described them in 1741. The Steller sea lion has attracted considerable attention in recent decades, owing to significant and largely unexplained declines in their numbers over an extensive portion of their northern range in Alaska. Description Adult animals are lighter in color than most sea lions, ranging from pale yellow to tawny and occasionally reddish. Steller sea lion pups are born almost black, weighing around , and remain dark in coloration for several months. Females and males both grow rapidly until the fifth year, after which female growth slow ...
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Peregrine Falcons
The peregrine falcon (''Falco peregrinus''), also known as the peregrine, and historically as the duck hawk in North America, is a cosmopolitan bird of prey (raptor) in the family Falconidae. A large, crow-sized falcon, it has a blue-grey back, barred white underparts, and a black head. The peregrine is renowned for its speed, reaching over during its characteristic hunting stoop (high-speed dive), making it the fastest bird in the world, as well as the fastest member of the animal kingdom. According to a ''National Geographic'' TV program, the highest measured speed of a peregrine falcon is . As is typical for bird-eating raptors, peregrine falcons are sexually dimorphic, with females being considerably larger than males. The peregrine's breeding range includes land regions from the Arctic tundra to the tropics. It can be found nearly everywhere on Earth, except extreme polar regions, very high mountains, and most tropical rainforests; the only major ice-free landmass from w ...
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Bald Eagles
The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as the bald eagle in the Palearctic. Its range includes most of Canada and Alaska, all of the contiguous United States, and northern Mexico. It is found near large bodies of open water with an abundant food supply and old-growth trees for nesting. The bald eagle is an opportunistic feeder which subsists mainly on fish, which it swoops down upon and snatches from the water with its talons. It builds the largest nest of any North American bird and the largest tree nests ever recorded for any animal species, up to deep, wide, and in weight. Sexual maturity is attained at the age of four to five years. Bald eagles are not actually bald; the name derives from an older meaning of the word, "white headed". The adult is mainly brown with a white ...
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Ancient Murrelet
The ancient murrelet (') is a bird in the auk family. The English term "murrelet" is a diminutive of "murre", a word of uncertain origins, but which may imitate the call of the common guillemot. Ancient murrelets are called "ancient" because they have grey on the back like a shawl, as worn by the elderly.Attenborough, D. 1998. ''The Life of Birds''. BBC Books. . Taxonomy The ancient murrelet was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's ''Systema Naturae''. He placed it with the auks in the genus '' Alca'' and coined the binomial name ''Alca antiqua''. Gmelin based his description on the "ancient auk" that had been described in 1785 by both the English ornithologist John Latham and the Welsh naturalist Thomas Pennant. Both authors mention a specimen in the Leverian Museum and give the location as the west of North America, the Kuril Islands and the Kamchatka Peninsula. The ancient murrelet ...
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