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Palinurus Charlestoni
''Palinurus charlestoni'' is a species of spiny lobster which is endemic to the waters of Cape Verde. It grows to a total length of and can be distinguished from other Atlantic species in the genus by the pattern of horizontal bands on its legs. It was discovered by French fishermen in 1963, and has been the subject of small-scale fishery since. It is thought to be overexploited, and is listed as ''Near Threatened'' on the IUCN Red List. Description The total length of ''Palinurus charlestoni'' can reach , with the average size around . Like other spiny lobsters, it has five pairs of pereiopods (walking legs), but no chelae (claws). Forest & Postel (1964), p. 105. In life, ''P. charlestoni'' is red to violet, but quite variable in colour. The carapace is red with white spots, while the abdomen is red with sharp white stripes on either side of the midline. Forest & Postel (1964), p. 106. ''P. charlestoni'' can be distinguished from the other Atlantic species of ''Pali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiny Lobster
Spiny lobsters, also known as langustas, langouste, or rock lobsters, are a family (Palinuridae) of about 60 species of achelate crustaceans, in the Decapoda Reptantia. Spiny lobsters are also, especially in Australia, New Zealand, Ireland, South Africa, and The Bahamas, called crayfish, sea crayfish, or crawfish ("kreef" in South Africa), terms which elsewhere are reserved for freshwater crayfish. Classification The furry lobsters (''e.g.'' ''Palinurellus'') were previously separated into a family of their own, the Synaxidae, but are usually considered members of the Palinuridae. The slipper lobsters (Scyllaridae) are their next-closest relatives, and these two or three families make up the Achelata. Genera of spiny lobsters include ''Palinurus'' and a number of anagrams thereof: ''Panulirus'', ''Linuparus'', ''etc.'' (Palinurus was a helmsman in Virgil's ''Æneid''.) In total, 12 extant genera are recognised, containing around 60 living species: *''Jasus'' Parker, 1883 * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Maturity
Sexual maturity is the capability of an organism to reproduce. In humans it might be considered synonymous with adulthood, but here puberty is the name for the process of biological sexual maturation, while adulthood is based on cultural definitions. Most multicellular organisms are unable to sexually reproduce at birth (animals) or germination (e.g. plants): depending on the species, it may be days, weeks, or years until they have developed enough to be able to do so. Also, certain cues may trigger an organism to become sexually mature. They may be external, such as drought (certain plants), or internal, such as percentage of body fat (certain animals). (Such internal cues are not to be confused with hormones, which directly produce sexual maturity – the production/release of those hormones is triggered by such cues.) Role of reproductive organs Sexual maturity is brought about by a maturing of the reproductive organs and the production of gametes. It may also be accompanied ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Near Threatened
A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature as that may be vulnerable to endangerment in the near future, but it does not currently qualify for the threatened status. The IUCN notes the importance of re-evaluating near-threatened taxon at appropriate intervals. The rationale used for near-threatened taxa usually includes the criteria of vulnerable which are plausible or nearly met, such as reduction in numbers or range. Near-threatened species evaluated from 2001 onwards may also be ones which are dependent on conservation efforts to prevent their becoming threatened, whereas before this conservation-dependent species were given a separate category ("Conservation Dependent"). Additionally, the 402 conservation-dependent taxa may also be considered near-threatened. IUCN Categories and Criteria version 2.3 Before 2001, the IUCN used the version 2.3 Categories and Criteria ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maximum Sustainable Yield
In population ecology and economics, maximum sustainable yield (MSY) is theoretically, the largest yield (or catch) that can be taken from a species' stock over an indefinite period. Fundamental to the notion of sustainable harvest, the concept of MSY aims to maintain the population size at the point of maximum growth rate by harvesting the individuals that would normally be added to the population, allowing the population to continue to be productive indefinitely. Under the assumption of logistic growth, resource limitation does not constrain individuals' reproductive rates when populations are small, but because there are few individuals, the overall yield is small. At intermediate population densities, also represented by half the carrying capacity, individuals are able to breed to their maximum rate. At this point, called the maximum sustainable yield, there is a surplus of individuals that can be harvested because growth of the population is at its maximum point due to the la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Closed Season
A hunting season is the designated time in which certain game animals can be killed in certain designated areas. In the United States, each state determines and sets its own specific dates to hunt the certain game animal, such as California, in which they designate certain zones, in which each have their own separate dates in order to legally hunt. In the United States, each state has primary responsibility and authority over the hunting of wildlife that resides within state boundaries. State wildlife agencies that sell hunting licenses are the best source of information regarding hunting seasons, areas open/closed to hunting, etc. Hunting of migratory birds such as ducks and geese A goose ( : geese) is a bird of any of several waterfowl species in the family Anatidae. This group comprises the genera '' Anser'' (the grey geese and white geese) and ''Branta'' (the black geese). Some other birds, mostly related to the she ... is managed cooperatively by state fish and wild ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minimum Landing Size
The minimum landing size (MLS) is the smallest fish measurement at which it is legal to keep or sell a fish. The MLS depends on the species of fish. Sizes also vary around the world, as they are legal definitions which are defined by the local regulatory authority. Commercial trawl and seine fisheries can control the size of their catch by adjusting the mesh size of their nets. Effect of selection on fish sizes The idea behind this limitation is that only the older, mature fish get taken, leaving juveniles behind to continue breeding and propagating their species. There is some criticism of this legal requirement, however, as it applies selection pressure to the fish: as the larger fish get taken, the genes for larger size are reduced or removed from the gene pool, while fish that mature at a smaller size continue breeding. The average size of fish shrinks over time. This has led to a collapse in the amount of fish being caught in some fisheries. Aboriginal Australians around Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic Horse Mackerel
The Atlantic horse mackerel (''Trachurus trachurus''), also known as the European horse mackerel or common scad, is a species of jack mackerel in the family Carangidae, the jacks, pompanos and trevallies. It is found in the eastern Atlantic Ocean off Europe and Africa and into the south-eastern Indian Ocean. It is an important species in commercial fisheries and is listed as a Vulnerable species on The IUCN Red List of Threatened Species. Description The Atlantic horse mackerel has quite a slender, quite compressed body with a large head in which the rear of the upper jaw reaches the front of the eye and the lower jaw projects beyond the upper jaw. The eye has a well developed adipose eyelid. It has two dorsal fins, the first is tall and has seven thin spines, with the final spine being much shorter than the others. The second dorsal fin is separated from the first by a narrow gap and is considerably longer than the first with 29-33 soft rays. The anal fin is about as long as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic Mackerel
The Atlantic mackerel (''Scomber scombrus''), also known as Boston mackerel, Norwegian mackerel, Scottish mackerel or just mackerel, is a species of mackerel found in the temperate waters of the Mediterranean Sea, the Black Sea, and the northern Atlantic Ocean, where it is extremely common and occurs in huge shoals in the epipelagic zone down to about . It spends the warmer months close to shore and near the ocean surface, appearing along the coast in spring and departing with the arrival of colder weather in the fall and winter months. During the fall and winter, it migrates out into deeper and more southern water, seeking warmer temperatures. The Atlantic mackerel's body is elongate, steel-blue marked with wavy black lines dorsally and silvery-white ventrally, its snout long and pointed. It possesses two spiny dorsal fins, which are spaced far apart, two pectoral fins, and small caudal and anal fins, also spaced far apart. 4-6 dorsal finlets and 5 anal finlets are typical among ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wire Netting
Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm A wire is a flexible strand of metal. Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Wire gauges come in various standard sizes, as expressed in terms of a gauge number. Wires are used to bear mechanical loads, often in the form of wire rope. In electricity and telecommunications signals, a "wire" can refer to an electrical cable, which can contain a "solid core" of a single wire or separate strands in stranded or braided forms. Usually cylindrical in geometry, wire can also be made in square, hexagonal, flattened rectangular, or other cross-sections, either for decorative purposes, or for technical purposes such as high-efficiency voice coils in loudspeakers. Edge-wound coil springs, such as the Slinky toy, are made of special flattened wire. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lobster Trap
A lobster trap or lobster pot is a portable trap that traps lobsters or crayfish and is used in lobster fishing. In Scotland (chiefly in the north), the word creel is used to refer to a device used to catch lobsters and other crustaceans. A lobster trap can hold several lobsters. Lobster traps can be constructed of wire and wood, or metal and netting or rigid plastic. An opening permits the lobster to enter a tunnel of netting or other one-way device. Pots are sometimes constructed in two parts, called the "chamber" or "kitchen", where there is bait, and exits into the "parlour", which prevents escape. Lobster pots are usually dropped to the sea floor, one or more at a time, sometimes up to 40 or more, and are marked by a buoy so they can be picked up later. Description The trap can consist of a wood frame surrounded by mesh. The majority of the newer traps found in the Northeast of the US and the Canadian Maritimes consist of a plastic-coated metal frame. A piece of bait, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Territorial Waters
The term territorial waters is sometimes used informally to refer to any area of water over which a sovereign state has jurisdiction, including internal waters, the territorial sea, the contiguous zone, the exclusive economic zone, and potentially the extended continental shelf. In a narrower sense, the term is used as a synonym for the territorial sea. Baseline Normally, the baseline from which the territorial sea is measured is the low-water line along the coast as marked on large-scale charts officially recognized by the coastal state. This is either the low-water mark closest to the shore, or alternatively it may be an unlimited distance from permanently exposed land, provided that some portion of elevations exposed at low tide but covered at high tide (like mud flats) is within of permanently exposed land. Straight baselines can alternatively be defined connecting fringing islands along a coast, across the mouths of rivers, or with certain restrictions across the mou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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