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Lake Char
''Salvelinus umbla'', also known as lake char, is a species of char found in certain lakes of the region of the Alps in Europe. This char species usually inhabits the deeper waters of the lakes, feeding on crustaceans, insects and benthic fauna. Larger specimens can be piscivores. They look for areas with pebbly or stony bottom on steep slopes, at depths between 30 and 120 m during the spawning season. Distribution This char species lives in alpine and subalpine glacial valley lakes of central Europe, between France and Austria and between Germany and Northern Italy. It has been introduced in high altitude lakes as well. Although it is assessed as a least concern species by IUCN, the eutrophication of the lakes in the Subalpine region, which began in the 1950s and peaked in 1979, badly affected ''Salvelinus umbla'' populations, which crashed during that period. The lake char became locally extinct in lakes such as Mondsee and other char species, such as ''Salvelinus profun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juvenile (organism)
A juvenile is an individual organism that has not yet reached its adult form, sexual maturity or size. Juveniles can look very different from the adult form, particularly in colour, and may not fill the same niche as the adult form. In many organisms the juvenile has a different name from the adult (see List of animal names). Some organisms reach sexual maturity in a short metamorphosis, such as eclosion in many insects. For others, the transition from juvenile to fully mature is a more prolonged process—puberty in humans and other species, for example. In such cases, juveniles during this transformation are sometimes called subadults. Many invertebrates, on reaching the adult stage, are fully mature and their development and growth stops. Their juveniles are larvae or nymphs. In vertebrates and some invertebrates (e.g. spiders), larval forms (e.g. tadpoles) are usually considered a development stage of their own, and "juvenile" refers to a post-larval stage that is not full ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IUCN
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natural resources. It is involved in data gathering and analysis, research, field projects, advocacy, and education. IUCN's mission is to "influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable". Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to sustainable development in its projects. IUCN does not itself aim to mobilize the public in support of nature conservation. It tries to influence the actions of governments, business and other stakeholders by providing information and advice and through building partnerships. The organization is best known to the wider ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cold Water Fish
Coldwater fish can have different meanings in different contexts. In the context of aquariums, it refers to fish species that do not require a heater to remain within tolerable temperatures in a typical indoor aquarium. However, most or all ornamental fish species are able to tolerate temperatures as low as or lower than room temperature, with most stenothermic tropical species having critical thermal minimums of around 10-12 °C. Although these fish are capable of surviving in unheated aquaria, their temperature preferences may vary. For example, koi, goldfish, and pond loaches are commonly considered to be cold-water fish because of their ability to survive at very low temperatures, but their temperature preferences and/or physiological optimal temperatures are 32 °C (90 °F), 24-31 °C (75-88 °F), and 26-28 °C (79-82 °F), respectively. Because many of the ornamental fish considered to be “coldwater fish” are more accurately eurythermal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Biology
Fish are Aquatic animal, aquatic, craniate, gill-bearing animals that lack Limb (anatomy), limbs with Digit (anatomy), digits. Included in this definition are the living hagfish, lampreys, and Chondrichthyes, cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a vertebrate, true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed placodermi, external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Ladoga
Lake Ladoga (; rus, Ла́дожское о́зеро, r=Ladozhskoye ozero, p=ˈladəʂskəjə ˈozʲɪrə or rus, Ла́дога, r=Ladoga, p=ˈladəɡə, fi, Laatokka arlier in Finnish ''Nevajärvi'' ; vep, Ladog, Ladoganjärv) is a freshwater lake located in the Republic of Karelia and Leningrad Oblast in northwestern Russia, in the vicinity of Saint Petersburg. It is the largest lake located entirely in Europe, the second largest lake after Baikal in Russia, and the 14th largest freshwater lake by area in the world. ''Ladoga Lacus'', a methane lake on Saturn's moon Titan, is named after the lake. Etymology In one of Nestor's chronicles from the 12th century a lake called "the Great Nevo" is mentioned, a clear link to the Neva River and possibly further to Finnish ''nevo'' 'sea' or ''neva'' 'bog, quagmire'. Evgeny Pospelov: ''Geographical names of the world. Toponymic dictionary.'' Second edition. Astrel, Moscow 2001, pp. 106f. Ancient Norse sagas and Hanseatic tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vättern
Vättern ( , ) is the second largest lake by surface area in Sweden, after Vänern, and the sixth largest lake in Europe. It is a long, finger-shaped body of fresh water in south central Sweden, to the southeast of Vänern, pointing at the tip of Scandinavia. Being a deep lake at or below sea level at its deepest point, Vättern is about 1/3 the surface area of Vänern but in spite of this contains roughly 1/2 of its water. Vättern drains into Motala ström through Bråviken into the Baltic Sea, but also has a downstream connection since 1832 through Göta Canal to Vänern and the Kattegat tributary of the Atlantic Ocean. The lake has plenty of sources from rivers and small lakes, with the highest located sources being near Nässjö on the South Swedish Highland near the southeastern shoreline. Name The name Vättern is closely related to "vatten", the Swedish word for water, and also means "water, lake". Geography The lake's total surface area is about , with a drainage ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sommen Charr
The Sommen charr ( sv, Sommenröding) is a population or subspecies of Arctic charr found in Lake Sommen. It is one of twenty-two species of fish found in the lake. This population and other Arctic charrs in southern Sweden are regarded as relict populations at the southern edge of the natural distribution of Arctic charrs. Survival of Arctic charrs at the southern edge of their natural range is explained by Lake Sommens having a great depth () with cold and oxygen-rich bottom waters. Sommen charr may also draw benefits from the lake's richness in fish species and the complex ecology it implies. Populations of Sommen charr declined over the 20th century, leading to the fish being declared endangered in 1970. The causes of the decline are likely to include overfishing, fishing of immature individuals, unnatural lake level changes (as the lake is regulated), and competition from introduced species. The largest known Sommen charr weighed almost , and was for a while the largest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salvelinus Alpinus
The Arctic char or Arctic charr (''Salvelinus alpinus'') is a cold-water fish in the family Salmonidae, native to alpine lakes and arctic and subarctic coastal waters. Its distribution is Circumpolar North. It spawns in freshwater and populations can be lacustrine, riverine, or anadromous, where they return from the ocean to their fresh water birth rivers to spawn. No other freshwater fish is found as far north; it is, for instance, the only fish species in Lake Hazen which extend up to on Ellesmere Island in the Canadian Arctic. It is one of the rarest fish species in Great Britain and Ireland, found mainly in deep, cold, glacial lakes, and is at risk there from acidification. In other parts of its range, such as the Nordic countries, it is much more common, and is fished extensively. In Siberia, it is known as ''golets'' () and it has been introduced in lakes where it sometimes threatens less hardy endemic species, such as the small-mouth char and the long-finned char ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sweden
Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, Finland to the east, and is connected to Denmark in the southwest by a bridgetunnel across the Öresund. At , Sweden is the largest Nordic country, the third-largest country in the European Union, and the fifth-largest country in Europe. The capital and largest city is Stockholm. Sweden has a total population of 10.5 million, and a low population density of , with around 87% of Swedes residing in urban areas in the central and southern half of the country. Sweden has a nature dominated by forests and a large amount of lakes, including some of the largest in Europe. Many long rivers run from the Scandes range through the landscape, primarily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence. More than 99% of all species that ever lived on Earth, amounting to over five billion species, are estimated to have died out. It is estimated that there are currently around 8.7 million species of eukaryote globally, and possibly many times more if microorganisms, like bacteria, are included. Notable extinct animal species include non-avian dinosaurs, saber-toothed cats, dodos, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salvelinus Profundus
''Salvelinus profundus'' (german: Tiefseesaibling 'Deepwater char') is a deepwater char species found only in deep areas of Lake Constance. This fish can reach in length and has a blunt snout with the mouth in subinferior position. Its lower fins have no white margins and its flanks are silvery to yellowish with pale blue spots; the belly can have a reddish color. History ''Salvelinus profundus'' was still a commercial species in the 1960s but the eutrophication of Lake Constance, which began in the 1950s and peaked in 1979, is thought to have affected egg development. Surveys undertaken in the last ten years failed to find any evidence of the survival of this deep-water trout, as well as of the Lake Constance whitefish ('' Coregonus gutturosus''), another fish species driven recently to extinction. The species had been reported extinct since the late 1970s but was officially declared so by the IUCN only in 2008. However, the fish species was rediscovered in 2016 during 'Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mondsee (lake)
Mondsee (''Moon Lake'') is a lake in the Upper Austrian part of the Salzkammergut and near the larger Attersee. Its southwestern shore marks the border between the states of Upper Austria and Salzburg and also between the Northern Limestone Alps in the south and the Sandstone zone of the northern Alps. The Drachenwand (''Dragonwall'') at the southern shore of the lake is an impressive sight. Mondsee is one of Austria's last privately owned lakes. In August 2008, owner Nicolette Wächter announced it was up for sale. In 1864, remains of neolithic pile dwellings were discovered in the lake. New species discovered in Lake Mondsee Two bacterial strains isolated from Lake Mondsee were recognized as new species and described as '' Polynucleobacter cosmopolitanus'' and '' Polynucleobacter duraquae'', respectively. Both species are non- pathogenic and dwell in the lake as part of its bacterioplankton. Fish community of Lake Mondsee Fish living in the lake: * esox * lake trout * brown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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