Salmon /ˈsæmən/ is the common name for several species of ray-finned fish in the family Salmonidae. Other fish in the family include trout, grayling. Salmon are native to tributaries of the North Atlantic and Pacific Ocean, many species of salmon have been introduced into non-native environments such as the Great Lakes of North America and Patagonia in South America. Salmon are intensively farmed in parts of the world. Typically, salmon are anadromous, they are born in water, migrate to the ocean. However, populations of species are restricted to fresh water through their lives. Various species of salmon display anadromous life strategies while others display freshwater resident life strategies, folklore has it that the fish return to the exact spot where they were born to spawn, tracking studies have shown this to be mostly true. A portion of a salmon run may stray and spawn in different freshwater systems. The percent of straying depends on the species of salmon, homing behavior has been shown to depend on olfactory memory.
The term salmon comes from the Latin salmo, which in turn may have originated from salire, the nine commercially important species of salmon occur in two genera. The genus Salmo contains the Atlantic salmon, found in the north Atlantic, the genus Oncorhynchus contains eight species which occur naturally only in the North Pacific. As a group, these are known as Pacific salmon, Chinook salmon have been introduced in New Zealand and Patagonia. Coho, freshwater sockeye, and Atlantic salmon have established in Patagonia. † Both the Salmo and Oncorhynchus genera contain a number of species referred to as trout, within Salmo, additional minor taxa have been called salmon in English, i. e. the Adriatic salmon and Black Sea salmon. The steelhead anadromous form of the rainbow trout migrates to sea, a number of other species have common names which refer to them as being salmon. The British Columbia salmon fossil provides evidence that the divergence between Pacific and Atlantic salmon had not yet occurred 40 million years ago, Both the fossil record and analysis of mitochondrial DNA suggest the divergence occurred by 10 to 20 million years ago.
This independent evidence from DNA analysis and the fossil record rejects the theory of salmon divergence. Atlantic salmon reproduce in northern rivers on both coasts of the Atlantic Ocean, landlocked salmon live in a number of lakes in eastern North America and in Northern Europe, for instance in lakes Sebago, Ladoga, Saimaa, Vänern, and Winnipesaukee
The Arctic Ocean is the smallest and shallowest of the worlds five major oceans. Alternatively, the Arctic Ocean can be seen as the northernmost part of the all-encompassing World Ocean, located mostly in the Arctic north polar region in the middle of the Northern Hemisphere, the Arctic Ocean is almost completely surrounded by Eurasia and North America. It is partly covered by sea ice throughout the year and almost completely in winter, the summer shrinking of the ice has been quoted at 50%. The US National Snow and Ice Data Center uses satellite data to provide a record of Arctic sea ice cover. The Arctic may become ice free for the first time in human history within a few years or by 2040, for much of European history, the north polar regions remained largely unexplored and their geography conjectural. He was probably describing loose sea ice known today as growlers or bergy bits, his Thule was probably Norway, early cartographers were unsure whether to draw the region around the North Pole as land or water.
The makers of navigational charts, more conservative than some of the more fanciful cartographers, tended to leave the region blank and this lack of knowledge of what lay north of the shifting barrier of ice gave rise to a number of conjectures. In England and other European nations, the myth of an Open Polar Sea was persistent, john Barrow, longtime Second Secretary of the British Admiralty, promoted exploration of the region from 1818 to 1845 in search of this. In the United States in the 1850s and 1860s, the explorers Elisha Kane, even quite late in the century, the eminent authority Matthew Fontaine Maury included a description of the Open Polar Sea in his textbook The Physical Geography of the Sea. Nevertheless, as all the explorers who travelled closer and closer to the reported, the polar ice cap is quite thick. Fridtjof Nansen was the first to make a crossing of the Arctic Ocean. The first surface crossing of the ocean was led by Wally Herbert in 1969, in a dog sled expedition from Alaska to Svalbard, with air support.
The first nautical transit of the pole was made in 1958 by the submarine USS Nautilus. Since 1937, Soviet and Russian manned drifting ice stations have extensively monitored the Arctic Ocean, scientific settlements were established on the drift ice and carried thousands of kilometres by ice floes. In World War II, the European region of the Arctic Ocean was heavily contested, the Arctic Ocean occupies a roughly circular basin and covers an area of about 14,056,000 km2, almost the size of Antarctica. The coastline is 45,390 km long and it is surrounded by the land masses of Eurasia, North America, and by several islands. It is connected to the Pacific Ocean by the Bering Strait and to the Atlantic Ocean through the Greenland Sea, countries bordering the Arctic Ocean are, Norway, Greenland and the United States. There are several ports and harbours around the Arctic Ocean In Alaska, in Canada, ships may anchor at Churchill in Manitoba, Nanisivik in Nunavut, Tuktoyaktuk or Inuvik in the Northwest territories
Gold is a chemical element with symbol Au and atomic number 79. In its purest form, it is a bright, slightly yellow, soft, malleable. Chemically, gold is a metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions, Gold often occurs in free elemental form, as nuggets or grains, in rocks, in veins, and in alluvial deposits. It occurs in a solid solution series with the element silver and naturally alloyed with copper. Less commonly, it occurs in minerals as gold compounds, often with tellurium, golds atomic number of 79 makes it one of the higher numbered, naturally occurring elements. It is thought to have produced in supernova nucleosynthesis, from the collision of neutron stars. Because the Earth was molten when it was formed, almost all of the present in the early Earth probably sank into the planetary core. Gold is resistant to most acids, though it does dissolve in aqua regia, a mixture of acid and hydrochloric acid. Gold dissolves in solutions of cyanide, which are used in mining and electroplating.
Gold dissolves in mercury, forming amalgam alloys, but this is not a chemical reaction, as a precious metal, gold has been used for coinage and other arts throughout recorded history. A total of 186,700 tonnes of gold is in existence above ground, the world consumption of new gold produced is about 50% in jewelry, 40% in investments, and 10% in industry. Gold is used in infrared shielding, colored-glass production, gold leafing, certain gold salts are still used as anti-inflammatories in medicine. As of 2014, the worlds largest gold producer by far was China with 450 tonnes, Gold is cognate with similar words in many Germanic languages, deriving via Proto-Germanic *gulþą from Proto-Indo-European *ǵʰelh₃-. The symbol Au is from the Latin, the Latin word for gold, the Proto-Indo-European ancestor of aurum was *h₂é-h₂us-o-, meaning glow. This word is derived from the root as *h₂éu̯sōs, the ancestor of the Latin word Aurora. This etymological relationship is presumably behind the frequent claim in scientific publications that aurum meant shining dawn, Gold is the most malleable of all metals, a single gram can be beaten into a sheet of 1 square meter, and an avoirdupois ounce into 300 square feet.
Gold leaf can be thin enough to become semi-transparent
Fishing is the activity of trying to catch fish. Fish are normally caught in the wild, techniques for catching fish include hand gathering, netting and trapping. Fishing may include catching aquatic animals other than fish, such as molluscs, crustaceans, the term is not normally applied to catching farmed fish, or to aquatic mammals, such as whales where the term whaling is more appropriate. According to United Nations FAO statistics, the number of commercial fishermen. Fisheries and aquaculture provide direct and indirect employment to over 500 million people in developing countries, in 2005, the worldwide per capita consumption of fish captured from wild fisheries was 14.4 kilograms, with an additional 7.4 kilograms harvested from fish farms. In addition to providing food, modern fishing is a recreational pastime, Fishing is an ancient practice that dates back to at least the beginning of the Upper Paleolithic period about 40,000 years ago. Isotopic analysis of the remains of Tianyuan man, a 40.
Archaeology features such as middens, discarded fish bones, and cave paintings show that sea foods were important for survival. During this period, most people lived a lifestyle and were, of necessity. However, where there are examples of permanent settlements such as those at Lepenski Vir. The British dogger was a type of sailing trawler from the 17th century. The Brixham trawler that evolved there was of a build and had a tall gaff rig. They were sufficiently robust to be able to tow large trawls in deep water, the great trawling fleet that built up at Brixham, earned the village the title of Mother of Deep-Sea Fisheries. The small village of Grimsby grew to become the largest fishing port in the world by the mid 19th century, an Act of Parliament was first obtained in 1796, which authorised the construction of new quays and dredging of the Haven to make it deeper. It was only in the 1846, with the expansion in the fishing industry. The foundation stone for the Royal Dock was laid by Albert the Prince consort in 1849, the dock covered 25 acres and was formally opened by Queen Victoria in 1854 as the first modern fishing port.
The elegant Brixham trawler spread across the world, influencing fishing fleets everywhere, by the end of the 19th century, there were over 3,000 fishing trawlers in commission in Britain, with almost 1,000 at Grimsby. These trawlers were sold to fishermen around Europe, including from the Netherlands, twelve trawlers went on to form the nucleus of the German fishing fleet
Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east, the state of Hawaii is an archipelago in the mid-Pacific Ocean. The U. S. territories are scattered about the Pacific Ocean, the geography and wildlife of the country are extremely diverse. At 3.8 million square miles and with over 324 million people, the United States is the worlds third- or fourth-largest country by area, third-largest by land area. It is one of the worlds most ethnically diverse and multicultural nations, paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago. European colonization began in the 16th century, the United States emerged from 13 British colonies along the East Coast. Numerous disputes between Great Britain and the following the Seven Years War led to the American Revolution. On July 4,1776, during the course of the American Revolutionary War, the war ended in 1783 with recognition of the independence of the United States by Great Britain, representing the first successful war of independence against a European power.
The current constitution was adopted in 1788, after the Articles of Confederation, the first ten amendments, collectively named the Bill of Rights, were ratified in 1791 and designed to guarantee many fundamental civil liberties. During the second half of the 19th century, the American Civil War led to the end of slavery in the country. By the end of century, the United States extended into the Pacific Ocean. The Spanish–American War and World War I confirmed the status as a global military power. The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the sole superpower. The U. S. is a member of the United Nations, World Bank, International Monetary Fund, Organization of American States. The United States is a developed country, with the worlds largest economy by nominal GDP. It ranks highly in several measures of performance, including average wage, human development, per capita GDP. While the U. S. economy is considered post-industrial, characterized by the dominance of services and knowledge economy, the United States is a prominent political and cultural force internationally, and a leader in scientific research and technological innovations.
In 1507, the German cartographer Martin Waldseemüller produced a map on which he named the lands of the Western Hemisphere America after the Italian explorer and cartographer Amerigo Vespucci
Birds, a subgroup of Reptiles, are the last living examples of Dinosaurs. Birds live worldwide and range in size from the 5 cm bee hummingbird to the 2.75 m ostrich. They rank as the class of tetrapods with the most living species, at ten thousand. Birds are the closest living relatives of crocodilians, the fossil record indicates that birds evolved from feathered ancestors within the theropod group of saurischian dinosaurs. True birds first appeared during the Cretaceous period, around 100 million years ago, especially those in the southern continents, survived this event and migrated to other parts of the world while diversifying during periods of global cooling. Primitive bird-like dinosaurs that lie outside class Aves proper, in the broader group Avialae, have been found dating back to the mid-Jurassic period, around 170 million years ago. Birds have wings which are more or less developed depending on the species, the digestive and respiratory systems of birds are uniquely adapted for flight.
Some bird species of aquatic environments, particularly seabirds and some waterbirds, have evolved for swimming. Many species annually migrate great distances, Birds are social, communicating with visual signals and bird songs, and participating in such social behaviours as cooperative breeding and hunting and mobbing of predators. The vast majority of species are socially monogamous, usually for one breeding season at a time, sometimes for years. Other species have breeding systems that are polygynous or, Birds produce offspring by laying eggs which are fertilised through sexual reproduction. They are usually laid in a nest and incubated by the parents, most birds have an extended period of parental care after hatching. Some birds, such as hens, lay eggs even when not fertilised, songbirds and other species are popular as pets. Guano is harvested for use as a fertiliser, Birds prominently figure throughout human culture. About 120–130 species have become extinct due to human activity since the 17th century, human activity threatens about 1,200 bird species with extinction, though efforts are underway to protect them.
Recreational birdwatching is an important part of the ecotourism industry, the first classification of birds was developed by Francis Willughby and John Ray in their 1676 volume Ornithologiae. Carl Linnaeus modified that work in 1758 to devise the taxonomic classification system currently in use, Birds are categorised as the biological class Aves in Linnaean taxonomy. Phylogenetic taxonomy places Aves in the dinosaur clade Theropoda, Aves and a sister group, the clade Crocodilia, contain the only living representatives of the reptile clade Archosauria
A mountain range is a geographic area containing numerous geologically related mountains. A mountain system or system of ranges, sometimes is used to combine several geological features that are geographically related. Mountain ranges are usually segmented by highlands or mountain passes and valleys, individual mountains within the same mountain range do not necessarily have the same geologic structure or petrology. They may be a mix of different orogenic expressions and terranes, for example thrust sheets, uplifted blocks, fold mountains, most geologically young mountain ranges on the Earths land surface are associated with either the Pacific Ring of Fire or the Alpide Belt. The Andes is 7,000 kilometres long and is considered the worlds longest mountain system. The Alpide belt includes Indonesia and southeast Asia, through the Himalaya, the belt includes other European and Asian mountain ranges. The Himalayas contain the highest mountains in the world, including Mount Everest, mountain ranges outside of these two systems include the Arctic Cordillera, the Urals, the Appalachians, the Scandinavian Mountains, the Altai Mountains and the Hijaz Mountains.
If the definition of a range is stretched to include underwater mountains. The mountain systems of the earth are characterized by a tree structure, the sub-range relationship is often expressed as a parent-child relationship. For example, the White Mountains of New Hampshire and the Blue Ridge Mountains are sub-ranges of the Appalachian Mountains, the Appalachians are the parent of the White Mountains and Blue Ridge Mountains, and the White Mountains and the Blue Ridge Mountains are children of the Appalachians. The position of mountains influences climate, such as rain or snow, when air masses move up and over mountains, the air cools producing orographic precipitation. As the air descends on the side, it warms again and is drier. Often, a shadow will affect the leeward side of a range. Mountain ranges are constantly subjected to forces which work to tear them down. Erosion is at work while the mountains are being uplifted and long after until the mountains are reduced to low hills, rivers are traditionally believed to be the principle erosive factor on mountain ranges, with their ability of bedrock incision and sediment transport.
The rugged topography of a range is the product of erosion. The basins adjacent to a mountain range are filled with sediments which are buried and turned into sedimentary rock. The early Cenozoic uplift of the Rocky Mountains of Colorado provides an example and this mass of rock was removed as the range was actively undergoing uplift
Gates of the Arctic National Park and Preserve
Gates of the Arctic National Park and Preserve is a U. S. National Park in Alaska. It is the northernmost national park in the U. S. the park consists primarily of portions of the Brooks Range of mountains. A large part of the park is protected in the Gates of the Arctic Wilderness which covers 7,167,192 acres, the wilderness area adjoins the Noatak Wilderness Area and together they form the largest contiguous wilderness in the United States. There are no roads in Gates of the Arctic National Park, in 2016, the park received just 10,047 visitors, while Grand Canyon National Park received nearly 6 million visitors in the same year. Camping is permitted throughout the park, but may be restricted by easements when crossing Native Corporation lands within the park, the park headquarters is in Fairbanks. Park Service operations in the park are managed from the Bettles Ranger Station, Gates of the Arctic National Park and Preserve lies to the west of the Dalton Highway, centered on the Brooks Range and covering the north and south slopes of the mountains.
The park includes the Endicott Mountains and part of the Schwatka Mountains, the majority of Gates of the Arctic is designated as national park, in which only subsistence hunting by local rural residents is permitted. Sport hunting is permitted in the national preserve. To hunt and trap in the preserve, a person must have all required licenses and permits, the eastern boundary of the park generally follows the Dalton Highway at a distance of a few miles, with the westernmost part of the Arctic National Wildlife Refuge 10 miles farther east. Kanuti National Wildlife Refuge is near the parks southeast boundary, Noatak National Preserve adjoins the western boundary, and the National Petroleum Reserve–Alaska adjoins the northwest corner of the park. Almost all of the park is designated as wilderness, with the exception of areas around Anaktuvuk Pass, a detached portion of the park surrounds the outlying Fortress Mountain and Castle Mountain to the north of the park. Ten small communities outside the boundaries are classified as resident zone communities.
They are Alatna, Ambler, Anaktuvuk Pass, Bettles/Evansville, Kobuk, Shungnak, there are no established roads, visitor facilities, or campgrounds in the park. The Dalton Highway comes within five miles of the eastern boundary. About 259,000 acres of the park and preserve are owned by corporations or the State of Alaska. 7,263,000 acres are protected in the Gates of the Arctic Wilderness, the park contains mountains such as the Arrigetch Peaks and Mount Igikpak. It extends to the east as far as the Middle Fork of the Koyukuk River, which is paralleled by the Dalton Highway, the park straddles the continental divide, separating the drainages of the Pacific and Arctic Oceans. The northernmost section of the park includes portions of the Arctic foothills tundra
The Arctic Circle is the most northerly of the abstract five major circles of latitude as shown on maps of the Earth. The region north of this circle is known as the Arctic, the position of the Arctic Circle is not fixed, as of 7 April 2017, it runs 66°33′46. 6″ north of the Equator. Its latitude depends on the Earths axial tilt, which fluctuates within a margin of 2° over a 40, 000-year period, the Arctic Circle is currently drifting northwards at a speed of about 15 m per year. The word arctic comes from the Greek word ἀρκτικός and that from the word ἄρκτος, directly on the Arctic Circle these events occur, in principle, exactly once per year, at the June and December solstices, respectively. That is true at sea level, those limits increase with elevation above sea level, tens of thousands of years ago, waves of people migrated from eastern Siberia across the Bering Strait into North America to settle. Much later, in the period, there has been migration into some Arctic areas by Europeans.
The largest communities north of the Arctic Circle are situated in Russia and Norway, Norilsk, Tromsø, rovaniemi in Finland is the largest settlement in the immediate vicinity of the Arctic Circle, lying slightly south of the line. In contrast, the largest North American community north of the Arctic Circle, of the Canadian and United States Arctic communities, Alaska is the largest settlement with about 4,000 inhabitants. The Arctic Circle is roughly 16,000 kilometres, the area north of the Circle is about 20,000,000 km2 and covers roughly 4% of Earths surface. The Arctic Circle passes through the Arctic Ocean, the Scandinavian Peninsula, North Asia, Northern America, the land within the Arctic Circle is divided among eight countries, Sweden, Russia, the United States, Canada and Iceland. In the interior, summers can be warm, while winters are extremely cold
Arctic National Wildlife Refuge
The Arctic National Wildlife Refuge is a national wildlife refuge in northeastern Alaska, United States. It consists of 19,286,722 acres in the Alaska North Slope region and it is the largest National Wildlife Refuge in the country, slightly larger than the Yukon Delta National Wildlife Refuge. The refuge is administered from offices in Fairbanks, just across the border in Yukon, are two Canadian National Parks and Vuntut. Collins and Sumner recruited Wilderness Society President Olaus Murie and his wife Margaret Murie into an effort to protect the area. It takes a lot of territory to keep alive, a living wilderness, for scientific observation. The Far North is a fragile place, the region first became a federal protected area in 1960 by order of Fred Andrew Seaton, Secretary of the Interior under U. S. President Dwight D. Eisenhower. In 1980, Congress passed the Alaska National Interest Lands Conservation Act, eight million acres of the refuge, the Mollie Beattie Wilderness, are designated as wilderness area.
The expansion of the refuge in 1980 designated 1.5 million acres of the plain as the 1002 area and mandated studies of the natural resources of this area. Congressional authorization is required before oil drilling may proceed in this area, the remaining 10.1 million acres of the refuge are designated as minimal management, a category intended to maintain existing natural conditions and resource values. These areas are suitable for wilderness designation, although there are no proposals to designate them as wilderness. There are currently no roads within or leading into the refuge, on the northern edge of the refuge is the Inupiat village of Kaktovik and on the southern boundary the Gwichin settlement of Arctic Village. A popular wilderness route and historic passage exists between the two villages, traversing the refuge and all its ecosystems from boreal, interior forest to Arctic Ocean coast. Generally, visitors access to the land by aircraft. In the United States, the location most remote from human trails, roads, or settlements is found here.
The refuge supports a variety of plant and animal life than any other protected area in the Arctic Circle. A continuum of six different ecozones spans about 200 miles north to south, fish such as dolly varden and Arctic cisco are found in nearshore waters. Coastal lands and sea ice are used by caribou seeking relief from biting insects during summer, the Arctic coastal plain stretches southward from the coast to the foothills of the Brooks Range. This area of rolling hills, small lakes, and north-flowing, braided rivers is dominated by tundra vegetation consisting of low shrubs, caribou travel to the coastal plain during June and July to give birth and raise their young
Wildlife of Alaska
The wildlife of Alaska is diverse and abundant. This article gives information on a selection of the animal species in Alaska. For a complete list of mammals in Alaska, see List of Alaska mammals Alaska contains about 98% of the U. S. brown bear population, an estimated 30,000 brown bears live in Alaska. Of that number, about 1,450 are harvested by hunters yearly, most brown bears in Alaska are grizzly bears, but Kodiak Island is home to Kodiak bears, another subspecies that is the largest type of brown bear in the world. The brown bear is the top predator in Alaska, the density of brown bear populations in Alaska varies according to the availability of food, and in some places is as high as one bear per square mile. Alaska’s McNeil River Falls has one of the largest brown bear population densities in the state, brown bears can be dangerous if they are not treated with respect. Between the years 1998 and 2002, there were an average of 14.6 brown bear attacks per year in the state, brown bears are most dangerous when they have just made a fresh kill, and when a sow has cubs.
The black bear is smaller than the brown bear. They are found in numbers on the mainland of Alaska, but are not found on the islands off of the Gulf of Alaska. Black bears have seen in Alaska in a few different shades of colors such as black, cinnamon. They are widely scattered over Alaska, and pose more of a problem to humans because they come in contact with them on a regular basis. They are considered a nuisance because they frequently stroll through local towns, backyards, while black bear attacks are exceedingly rare, they can pose a risk to public safety when food conditioned and habituated to humans due to an availability of human food sources. As many as 100,000 black bears live in Alaska, alaskas polar bear populations are concentrated along its Arctic coastlines. In the winter, they are most common in the Kuskokwim Delta, St. Matthew Island, during the summer months, they migrate to the coastlines of the Arctic Ocean and the Chukchi Sea. There are two polar bear populations in Alaska.
The Chukchi population is found off in the part of Alaska near the Wrangell Islands. Until the late 1940s, polar bears were hunted almost exclusively for subsistence by Inupiats and dogs teams, though from the late 1940s until 1972, sport hunting by others took place. The 1959 Statehood Act set up a program for polar bear management, polar bear populations may be threatened by oil development and global warming