|
Salvelinus Umbla
''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 profund ... [...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] |
