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Bigeye Tuna
The bigeye tuna (''Thunnus obesus'') is a species of true tuna of the genus ''Thunnus'', belonging to the wider mackerel family Scombridae. In Hawaiian, it is one of two species known as ahi, the other being the yellowfin tuna. Bigeye tuna are found in the open waters of all tropical and temperate oceans, but not in the Mediterranean Sea. Description Bigeye tuna can grow up to 250 centimetres (98 inches) or 8 feet, in length. Maximum weight of individuals probably exceeds , with the all-tackle angling record standing at . They are large, deep-bodied, streamlined fish with large heads and eyes. The pectoral fins are very long, reaching back beyond the start of the second dorsal fin in juveniles and the space between the first and second dorsal fin in adults. They have 13 or 14 dorsal spines. Physiology Bigeye tuna have a unique physiology which allows them to forage in deeper colder waters and tolerate oxygen-poor waters. Bigeye tuna are reported to tolerate ambient oxygen levels ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The IUCN Red List Of Threatened Species
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biological species. It uses a set of precise criteria to evaluate the extinction risk of thousands of species and subspecies. These criteria are relevant to all species and all regions of the world. With its strong scientific base, the IUCN Red List is recognized as the most authoritative guide to the status of biological diversity. A series of Regional Red Lists are produced by countries or organizations, which assess the risk of extinction to species within a political management unit. The aim of the IUCN Red List is to convey the urgency of conservation issues to the public and policy makers, as well as help the international community to reduce species extinction. According to IUCN the formally stated goals of the Red List are to provide sc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsum (biology)
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axis, anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overfishing
Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing fish stock), resulting in the species becoming increasingly underpopulated in that area. Overfishing can occur in water bodies of any sizes, such as ponds, wetlands, rivers, lakes or oceans, and can result in resource depletion, reduced biological growth rates and low biomass levels. Sustained overfishing can lead to critical depensation, where the fish population is no longer able to sustain itself. Some forms of overfishing, such as the overfishing of sharks, has led to the upset of entire marine ecosystems. Types of overfishing include: growth overfishing, recruitment overfishing, ecosystem overfishing. The ability of a fishery to recover from overfishing depends on whether its overall carrying capacity and the variety of ecological conditions are suitable for t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Commission For The Conservation Of Atlantic Tunas
/ es, Comisión Internacional para la Conservación del Atún Atlántico (CICAA) , motto = , formation = , type = tuna regional fishery management organisation , status = , purpose = Fisheries management , headquarters = Madrid, Spain , membership = 52 members , coords = , area_served = Atlantic Ocean , founder = , leader_title = Executive Secretary , leader_name = Camille Jean Pierre Manel , website = The International Commission for the Conservation of Atlantic Tunas (ICCAT) is a tuna regional fishery management organisation, responsible for the management and conservation of tuna and tuna-like species in the Atlantic Ocean and adjacent seas. The organization was established in 1966, at a conference in Rio de Janeiro, Brazil, and operates in English, French and Spanish. The organisation has been strongly criticised by scientists for its repeated failure to conserve the sustainability ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Ocean Tuna Commission
, motto = , formation = , type = International organization , status = , purpose = Fisheries , headquarters = Victoria, Seychelles , membership = 32 state members , coords = , area_served = Indian Ocean , founder = , leader_title = Executive Secretary , leader_name = Chris O'Brien , website = The Indian Ocean Tuna Commission (IOTC; french: CTOI) is an intergovernmental organization that co-ordinates the regulation and management of tuna in the Indian Ocean. Conceived in 1993, it entered into existence in 1996. A multilateral treaty, the Agreement for the Establishment of the Indian Ocean Tuna Commission was approved by the Council of the Food and Agriculture Organization of the United Nations in November 1993. The agreement entered into force on 27 March 1996 after it had been accepted by a tenth party. The Agreement is ope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inter-American Tropical Tuna Commission
, motto = , formation = , type = tuna regional fishery management organisation , status = International organization , purpose = Fisheries management , headquarters = La Jolla, San Diego, United States , membership = 21 members , coords = , area_served = Eastern Pacific Ocean , founder = , leader_title = Director , leader_name = Arnulfo Franco , website = The Inter-American Tropical Tuna Commission (abbreviated IATTC) ( Sp.: ''Comisión Interamericana del Atún Tropical'') is a tuna regional fishery management organisation responsible for the conservation and management of tuna and other marine resources in the eastern Pacific Ocean. History The Inter-American Tropical Tuna Commission was created by the Convention for the Establishment of an Inter-American Tropical Tuna Commission, signed between the United States and Costa Rica on May 31, 1949. The Convention was signed by United States ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western And Central Pacific Fisheries Commission
The Western and Central Pacific Fisheries Commission (WCPFC) is both a general and a tuna regional fisheries management organisation established to conserve and manage tuna and other highly migratory fish stocks across the western and central areas of the Pacific Ocean. Its full name is Commission for the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean. It commenced operations in late 2005, and its secretariat is based in Pohnpei, in the northern Pacific state of the Federated States of Micronesia. It was established by the international treaty ''Convention on the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean'' (WCPF Convention), which entered into force on . The WCPF Convention is the second regional fisheries management agreement negotiated since the conclusion of the 1995 U.N. Fish Stocks Agreement. Operation The WCPF Convention was based on the 1995 UN Fish Stocks Agr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thunnus Obesus
The bigeye tuna (''Thunnus obesus'') is a species of true tuna of the genus ''Thunnus'', belonging to the wider mackerel family Scombridae. In Hawaiian, it is one of two species known as ahi, the other being the yellowfin tuna. Bigeye tuna are found in the open waters of all tropical and temperate oceans, but not in the Mediterranean Sea. Description Bigeye tuna can grow up to 250 centimetres (98 inches) or 8 feet, in length. Maximum weight of individuals probably exceeds , with the all-tackle angling record standing at . They are large, deep-bodied, streamlined fish with large heads and eyes. The pectoral fins are very long, reaching back beyond the start of the second dorsal fin in juveniles and the space between the first and second dorsal fin in adults. They have 13 or 14 dorsal spines. Physiology Bigeye tuna have a unique physiology which allows them to forage in deeper colder waters and tolerate oxygen-poor waters. Bigeye tuna are reported to tolerate ambient oxygen levels ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephalopods
A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles (muscular hydrostats) modified from the primitive molluscan foot. Fishers sometimes call cephalopods "inkfish", referring to their common ability to squirt ink. The study of cephalopods is a branch of malacology known as teuthology. Cephalopods became dominant during the Ordovician period, represented by primitive nautiloids. The class now contains two, only distantly related, extant subclasses: Coleoidea, which includes octopuses, squid, and cuttlefish; and Nautiloidea, represented by ''Nautilus'' and ''Allonautilus''. In the Coleoidea, the molluscan shell has been internalized or is absent, whereas in the Nautiloidea, the external shell remains. About 800 living species of cephalopods have been identified. Tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustaceans
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans (Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sound Scattering Layer
The deep scattering layer, sometimes referred to as the sound scattering layer, is a layer in the ocean consisting of a variety of marine animals. It was discovered through the use of sonar, as ships found a layer that scattered the sound and was thus sometimes mistaken for the seabed. For this reason it is sometimes called the false bottom or phantom bottom. It can be seen to rise and fall each day in keeping with diel vertical migration. Sonar operators, using the newly developed sonar technology during World War II, were puzzled by what appeared to be a false sea floor 300–500 metres (980–1,640 ft) deep at day, and less deep at night. Initially, this mysterious phenomenon was called the ECR layer using the initials of its three discoverers. It turned out to be due to millions of marine organisms, most particularly small mesopelagic fish, with swim bladders that reflected the sonar. These organisms migrate up into shallower water at dusk to feed on plankton. The layer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diel Vertical Migration
Diel vertical migration (DVM), also known as diurnal vertical migration, is a pattern of movement used by some organisms, such as copepods, living in the ocean and in lakes. The word ''diel'' comes from the Latin ''dies'' day, and means a 24-hour period. The migration occurs when organisms move up to the uppermost layer of the sea at night and return to the bottom of the daylight zone of the oceans or to the dense, bottom layer of lakes during the day. It is important to the functioning of deep-sea food webs and the biologically driven sequestration of carbon. In terms of biomass, it is the largest synchronous migration in the world. It is not restricted to any one taxon as examples are known from crustaceans (copepods), molluscs (squid), and ray-finned fishes (trout). The phenomenon may be advantageous for a number of reasons, most typically to access food and avoid predators. It is triggered by various stimuli, the most prominent being response to changes in light i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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