|
Channichthys Rhinoceratus
''Channichthys rhinoceratus,'' the unicorn icefish, is a species of marine ray-finned fish belonging to the Family (biology), family Channichthyidae, the crocodile icefishes. It is Endemism, endemic to the Kerguelen Plateau, Kerguelen-Heard Plateau in the Southern Ocean. It is a Demersal fish, demersal species living from Pelagic zone, surface waters to depths up to . It is considered by some researchers as the only species in the genus ''Channichthys.'' Description Described by John Richardson (naturalist), Sir John Richardson in 1844 and being the type species of the genus ''Channichthys'', the unicorn icefish is generally pale brown, though smaller specimens have four dark cross-bars present on each side of the body, and dark spots are present on the body, sometimes with reddish patches and dark reticulations are present. Dark spots may be present on the blackish first dorsal fin. Other fins are colored pale or dusky. It grows up to a maximum length of 60 cm (24 inches) and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Richardson (naturalist)
Sir John Richardson Royal Society of London, FRS FRSE (5 November 1787 – 5 June 1865) was a Scotland, Scottish naval surgeon, natural history, naturalist and Arctic explorer. Life Richardson was born at Nith Place in Dumfries the son of Gabriel Richardson, Provost of Dumfries, and his wife, Anne Mundell. He was educated at Dumfries Grammar School. He was then apprenticed to his maternal uncle, Dr James Mundell, a surgeon in Dumfries. He studied medicine at Edinburgh University, and became a surgeon in the navy in 1807. He traveled with John Franklin in search of the Northwest Passage on the Coppermine Expedition of 1819–1822. Richardson wrote the sections on geology, botany and ichthyology for the official account of the expedition. Franklin and Richardson returned to Canada in 1825 and went overland by fur trade routes to the mouth of the Mackenzie River. Franklin was to go as far west as possible and Richardson was to go east to the mouth of the Coppermine River. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Channichthys Mithridatis
''Channichthys mithridatis'', the green icefish, is a species of marine ray-finned fish belonging to the family Channichthyidae, the crocodile icefishes. It is endemic to the Kerguelen Islands in the Southern Ocean. Taxonomy ''Channichthys mithridatis'' was first formally described in 2008 by Gennadiy A. Shandikov with the type locality given as Kerguelen Island. Fishbase treats ''C. mithridatis'' as a valid species but '' Catalog of Fishes'' treats it as a junior synonym of '' C. rhinoceratus''. The specific name ''mithridatis'' is a Latinisation of Mithridates, the King of Pontus in the Hellenistic period who ruled over Panticapaeum, the modern city of Kerch in the Crimea where the institute yugNIRO which staudied Antractic fisheries was based. Description ''Channichthys mithridatis'' attains a maximum total length of . The first dorsal fin has spines and there are 32-34 dorsal fin rays while the anal fin contains 30-32 soft rays. The overall colour of the body and head v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Of The Southern Ocean
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] |
Bycatch
Bycatch (or by-catch), in the fishing industry, is a fish or other marine species that is caught unintentionally while fishing for specific species or sizes of wildlife. Bycatch is either the wrong species, the wrong sex, or is undersized or juveniles of the target species. The term "bycatch" is also sometimes used for untargeted catch in other forms of animal harvesting or collecting. Non- marine species (freshwater fish not saltwater fish) that are caught (either intentionally or unintentionally) but regarded as generally "undesirable" are referred to as "rough fish" (mainly US) and " coarse fish" (mainly UK). In 1997, the Organisation for Economic Co-operation and Development (OECD) defined bycatch as "total fishing mortality, excluding that accounted directly by the retained catch of target species". Bycatch contributes to fishery decline and is a mechanism of overfishing for unintentional catch. The average annual bycatch rate of pinnipeds and cetaceans in the US from 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bottom Trawling
Bottom trawling is trawling (towing a trawl, which is a fishing net) along the seafloor. It is also referred to as "dragging". The scientific community divides bottom trawling into benthic trawling and demersal trawling. Benthic trawling is towing a net at the very bottom of the ocean and demersal trawling is towing a net just above the benthic zone. Bottom trawling can be contrasted with midwater trawling (also known as pelagic trawling), where a net is towed higher in the water column. Midwater trawling catches pelagic fish such as anchovies and mackerel, whereas bottom trawling targets both bottom-living fish (groundfish) and semi-pelagic species such as cod, squid, shrimp, and rockfish. Trawling is done by a trawler, which can be a small open boat with only or a large factory trawler with . Bottom trawling can be carried out by one trawler or by two trawlers fishing cooperatively (pair trawling). Global catch from bottom trawling has been estimated at over 30 million tonnes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commercial Fisheries
Commercial fishing is the activity of catching fish and other seafood for commercial profit, mostly from wild fisheries. It provides a large quantity of food to many countries around the world, but those who practice it as an industry must often pursue fish far into the ocean under adverse conditions. Large-scale commercial fishing is also known as industrial fishing. The major fishing industries are not only owned by major corporations but by small families as well. In order to adapt to declining fish populations and increased demand, many commercial fishing operations have reduced the sustainability of their harvest by fishing further down the food chain. This raises concern for fishery managers and researchers, who highlight how further they say that for those reasons, the sustainability of the marine ecosystems could be in danger of collapsing. Commercial fishermen harvest a wide variety of animals. However, a very small number of species support the majority of the world' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marion Island
The Prince Edward Islands are two small uninhabited islands in the sub-Antarctic Indian Ocean that are part of South Africa. The islands are named Marion Island (named after Marc-Joseph Marion du Fresne, 1724–1772) and Prince Edward Island (named after Prince Edward, Duke of Kent and Strathearn, 1767–1820). The islands in the group have been declared Special Nature Reserves under the South African Environmental Management: Protected Areas Act, No. 57 of 2003, and activities on the islands are therefore restricted to research and conservation management. Further protection was granted when the area was declared a marine protected area in 2013. The only human inhabitants of the islands are the staff of a meteorological and biological research station run by the South African National Antarctic Programme on Marion Island. History The islands were discovered on 4 March 1663 by Barent Barentszoon Lam of the Dutch East India Company ship ''Maerseveen'' and were named ''Dina' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gentoo Penguin
The gentoo penguin ( ) (''Pygoscelis papua'') is a penguin species (or possibly a species complex) in the genus ''Pygoscelis'', most closely related to the Adélie penguin (''P. adeliae'') and the chinstrap penguin (''P. antarcticus''). The earliest scientific description was made in 1781 by Johann Reinhold Forster with a type locality in the Falkland Islands. The species calls in a variety of ways, but the most frequently heard is a loud trumpeting, which the bird emits with its head thrown back. Names The application of "gentoo" to the penguin is unclear. '' Gentoo'' was an Anglo-Indian term to distinguish Hindus from Muslims. The English term may have originated from the Portuguese ''gentio'' ("pagan, gentile"). Some speculate that the white patch on the bird's head was thought to resemble a turban. It may also be a variation of another name for this bird, "Johnny penguin", with Johnny being in Spanish and sounds vaguely like gentoo. The Johnny rook, a predator, is likely ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otolith
An otolith ( grc-gre, ὠτο-, ' ear + , ', a stone), also called statoconium or otoconium or statolith, is a calcium carbonate structure in the saccule or utricle of the inner ear, specifically in the vestibular system of vertebrates. The saccule and utricle, in turn, together make the ''otolith organs''. These organs are what allows an organism, including humans, to perceive linear acceleration, both horizontally and vertically (gravity). They have been identified in both extinct and extant vertebrates. Counting the annual growth rings on the otoliths is a common technique in estimating the age of fish. Description Endolymphatic infillings such as otoliths are structures in the saccule and utricle of the inner ear, specifically in the vestibular labyrinth of all vertebrates (fish, amphibians, reptiles, mammals and birds). In vertebrates, the saccule and utricle together make the ''otolith organs''. Both statoconia and otoliths are used as gravity, balance, movement, and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black-browed Albatross
The black-browed albatross (''Thalassarche melanophris''), also known as the black-browed mollymawk,Robertson, C. J. R. (2003) is a large seabird of the albatross family Diomedeidae; it is the most widespread and common member of its family. Taxonomy Mollymawks are albatrosses in the family Diomedeidae and order Procellariiformes, which also includes shearwaters, fulmars, storm petrels, and diving petrels. These birds share certain identifying features. They have nasal passages that attach to the upper bill called naricorns, although the nostrils on the albatross are on the sides of the bill. The bills of Procellariiformes are also unique in that they are split into between seven and nine horny plates. They produce a stomach oil made up of wax esters and triglycerides that is stored in the proventriculus. This is used against predators as well as being an energy-rich food source for chicks and also for the adults during their long flights. The albatross also has a salt gland a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algae
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as ''Chlorella,'' ''Prototheca'' and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to in length. Most are aquatic and autotrophic (they generate food internally) and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the ''Charophyta'', a division of green algae which includes, for example, ''Spirogyra'' and stoneworts. No definition of algae is generally accepted. One definition is that algae "have chlorophyll ''a'' as their primary photosynthetic pigment and lack a sterile covering of cells around thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harpagifer
''Harpagifer'', the spiny plunderfishes is a genus of marine ray-finned fishes, belonging to the family Harpagiferidae, it is the only genus in this monotypic family. They are found in the Southern Ocean. Taxonomy The genus ''Harpagifer'' was described in 1844 by the Scottish naval surgeon, naturalist and Arctic explorer John Richardson, with ''Batrachus bispinis'', a species which had been described in 1801 by Johann Reinhold Forster, as its type species by monotypy. In 1961 the American ichthyologist Theodore Nicholas Gill realised that these fishes were different enough from other Notothenioid fishes that they should be placed in their own family which called Harpagiferoidae, although this is now spelled Harpagiferidae. The name of the genus ''Harpagifer'' compounds ''harpagos'' which means "hook" and ''fero'' meaning "to bear", a reference to the spine on the operculum of ''H. bispinis''. Species There are currently 12 recognized species in this genus: * '' Harpagifer and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
