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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. The closest relative of the capelin appears to have be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spawn (biology)
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of freely releasing eggs and sperm into a body of water (fresh or marine); the physical act is known as spawning. The vast majority of aquatic and amphibious animals reproduce through spawning. These include the following groups: * Bony fishes * Crustaceans (such as crabs, shrimps, etc.) *Mollusks (such as oysters, octopus, squid) *Echinoderms (such as sea urchins, sea stars, sea cucumbers, etc.) * Amphibians (such as frogs, toads, salamanders, newts) * Aquatic insects (such as dragonflies, mayflies, mosquitoes) *Coral, which are living colonies of tiny, aquatic organisms—not plants, as they are sometimes perceived to be. Corals, while appearing sedentary or botanical by nature, actually spawn by releasing clouds of sperm and egg cells into the water column, where the two mix. As a general rule, aquatic or semiaquatic reptiles, birds, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forage Fish
Forage fish, also called prey fish or bait fish, are small pelagic fish that feed on planktons (i.e. planktivores) and other small aquatic organisms (e.g. krill). They are in turn preyed upon by various predators including larger fish, seabirds and marine mammals, this making them keystone species in their aquatic ecosystems. The typical ocean forage fish feed at the lower trophic level of the food chain, 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, Atheriniformes, silversides, Smelt (fish), smelt such as capelin and goldband fusiliers. Forage fish compensate for their small size by forming shoaling and schooling, schools. Some swim in synchronised grids with their mouths open so they can efficiently filter plankton. These schools can become immense Shoaling and schooling, shoals which move along coastlines and Fish migration, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shoaling And Schooling
In biology, any group of fish that stay together for social reasons are shoaling, and if the group is swimming in the same direction in a coordinated manner, they are schooling. In common usage, the terms are sometimes used rather loosely. About one quarter of fish species shoal all their lives, and about one half shoal for part of their lives. Fish derive many benefits from shoaling behaviour including defence against predators (through better predator detection and by diluting the chance of individual capture), enhanced foraging success, and higher success in finding a mate. It is also likely that fish benefit from shoal membership through increased hydrodynamic efficiency. Fish use many traits to choose shoalmates. Generally they prefer larger shoals, shoalmates of their own species, shoalmates similar in size and appearance to themselves, healthy fish, and kin (when recognized). The oddity effect posits that any shoal member that stands out in appearance will be preferen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Migration
Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousands of kilometres. Such migrations are usually done for better feeding or to reproduce, but in other cases the reasons are unclear. Fish migrations involve movements of schools of fish on a scale and duration larger than those arising during normal daily activities. Some particular types of migration are ''anadromous'', in which adult fish live in the sea and migrate into fresh water to spawn; and ''catadromous'', in which adult fish live in fresh water and migrate into salt water to spawn. Marine forage fish often make large migrations between their spawning, feeding and nursery grounds. Their movements are associated with ocean currents and with the availability of food in different areas at different times of the year. The migratory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barents Sea
The Barents Sea ( , also ; , ; ) is a marginal sea of the Arctic Ocean, located off the northern coasts of Norway and Russia and divided between Norwegian and Russian territorial waters.World Wildlife Fund, 2008. It was known earlier among Russians as the Northern Sea, Pomorsky Sea or Murman Sea ("Norse Sea"); the current name of the sea is after the historical Netherlands, Dutch navigator Willem Barentsz. The Barents Sea is a rather shallow Continental shelf, shelf sea with an average depth of , and it is an important site for both fishing and hydrocarbon exploration.O. G. Austvik, 2006. It is bordered by the Kola Peninsula to the south, the shelf edge towards the Norwegian Sea to the west, the archipelagos of Svalbard to the northwest, Franz Josef Land to the northeast and Novaya Zemlya to the east. The islands of Novaya Zemlya, an extension of the northern end of the Ural Mountains, separate the Barents Sea from the Kara Sea. Although part of the Arctic Ocean, the Barents Sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic Cod
The Atlantic cod (: cod; ''Gadus morhua'') is a fish of the family Gadidae, widely consumed by humans. It is also commercially known as '' cod'' or ''codling''.''Atlantic Cod'' . Seafood Portal. In the western Atlantic Ocean, cod has a distribution north of Cape Hatteras, , and around both coasts of and the ; in the easte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enoplophthalmus
''Enoplophthalmus'' is an extinct genus of prehistoric freshwater smelt that inhabited Europe during the Oligocene and early Miocene epoches, from the Rupelian to the Aquitanian. It appears to be closely related to the modern capelin (''Mallotus villosus''). Until the description of the Paleocene-aged '' Speirsaenigma'' from Canada, it was the oldest known fossil smelt genus. The following species are known: * †''E. alsaticus'' Gaudant, 1984 - Early Oligocene of France ( Pechelbronn Formation), potentially late Oligocene of Armenia * †''E. rhenanus'' (Weiler, 1963) - Early Miocene ( Aquitanian) of Germany ( Hydrobienkalk Formation) * †''E. robustus'' (Weiler, 1963) - Early Miocene (Aquitanian) of Germany (Hydrobienkalk Formation) * †''E. schlumbergeri'' Sauvage, 1880 (type species) - Early Oligocene of France ( Calcaires de Campagne-Calavon) Indeterminate otoliths of this genus are known from Romania. Alongside '' Dapalis'', ''Enoplopthalmus'' appears to have been on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Ocean
The Arctic Ocean is the smallest and shallowest of the world's five oceanic divisions. It spans an area of approximately and is the coldest of the world's oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, although some oceanographers call it the Arctic Mediterranean Sea. It has also been described as an estuary of the Atlantic Ocean. It is also seen as the northernmost part of the all-encompassing world ocean. The Arctic Ocean includes the North Pole region in the middle of the Northern Hemisphere and extends south to about 60°N. The Arctic Ocean is surrounded by Eurasia and North America, and the borders follow topographic features: the Bering Strait on the Pacific side and the Greenland Scotland Ridge on the Atlantic side. It is mostly covered by sea ice throughout the year and almost completely in winter. The Arctic Ocean's surface temperature and salinity vary seasonally as the ice cover melts and freezes; its salinity is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Atlantic
The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for separating the New World of the Americas (North America and South America) from the Old World of Afro-Eurasia (Africa, Asia, and Europe). Through its separation of Afro-Eurasia from the Americas, the Atlantic Ocean has played a central role in the development of human society, globalization, and the histories of many nations. While the Norse were the first known humans to cross the Atlantic, it was the expedition of Christopher Columbus in 1492 that proved to be the most consequential. Columbus's expedition ushered in an age of exploration and colonization of the Americas by European powers, most notably Portugal, Spain, France, and the United Kingdom. From the 16th to 19th centuries, the Atlantic Ocean was the center of both an epo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smelt (fish)
Smelts are a family of small fish, the Osmeridae, found in the North Atlantic and North Pacific oceans, as well as rivers, streams and lakes in Europe, North America and Northeast Asia. They are also known as freshwater smelts or typical smelts to distinguish them from the related Argentinidae (herring smelts or argentines), Bathylagidae (deep-sea smelts), and Retropinnidae (Australian and New Zealand smelts). Some smelt species are common in the North American Great Lakes, and in the lakes and seas of the northern part of Europe, where they run in large Shoaling and schooling, schools along the saltwater coastline during spring migration to their spawning streams. In some western parts of the United States, smelt populations have greatly declined in recent decades, leading to their protection under the Endangered Species Act. The Delta smelt (''Hypomesus transpacificus'') found in the Sacramento Delta of California, and the eulachon (''Thaleichthys pacificus'') found in the Nor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jan Mayen
Jan Mayen () is a Norway, Norwegian volcanic island in the Arctic Ocean with no permanent population. It is long (southwest-northeast) and in area, partly covered by glaciers (an area of around the Beerenberg volcano). It has two parts: larger northeast Nord-Jan and smaller Sør-Jan, linked by a wide isthmus. It lies northeast of Iceland (495 km [305 mi] NE of Kolbeinsey), east of central Greenland, and northwest of Vesterålen, Norway. The island is mountainous, the highest summit being the Beerenberg volcano in the north. The isthmus is the location of the two largest lakes of the island, Sørlaguna (South Lagoon) and Nordlaguna (North Lagoon). A third lake is called Ullerenglaguna (Ullereng Lagoon). Jan Mayen was formed by the Jan Mayen hotspot and is defined by geologists as a Continental fragment, microcontinent. Although administered separately, in the ISO 3166-1 standard, Jan Mayen and Svalbard are collectively designated as ''Svalbard and Jan Mayen'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenland
Greenland is an autonomous territory in the Danish Realm, Kingdom of Denmark. It is by far the largest geographically of three constituent parts of the kingdom; the other two are metropolitan Denmark and the Faroe Islands. Citizens of Greenland are full Danish nationality law, citizens of Denmark and European Union citizenship, of the European Union. Greenland is one of the Special territories of members of the European Economic Area#Overseas countries and territories, Overseas Countries and Territories of the European Union and is part of the Council of Europe. It is the List of islands by area, world's largest island, and lies between the Arctic Ocean, Arctic and Atlantic oceans, east of the Arctic Archipelago, Canadian Arctic Archipelago. It is the location of the northernmost point of land in the world; Kaffeklubben Island off the northern coast is the world's Northernmost point of land, northernmost undisputed point of land—Cape Morris Jesup on the mainland was thought to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
