It had not been dead long; its swim bladder was still intact.
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But in China, the totoaba's swim bladder is thought to have medicinal powers.
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Why do diners in China want to eat the swim bladder of that endangered fish?
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Fishermen target the totoaba for its swim bladder, which is prized in Asian cultures for making soup.
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Fishermen use the same method to detect fish by pinging the critter's buoyant air-filled swim bladder.
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"On the inside here right behind near the spine is its swim bladder," said crew member Adam Conniss.
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Vaquita populations have been decimated by illegal nets used to catch totoaba fish, whose swim bladder is prized in China.
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Demand in China for the endangered totoaba's swim bladder, considered to be a delicacy, drives a far-flung criminal network.
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Other fish are able to hear because of the swim bladder, a pouch inside their bodies that helps them stay afloat.
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The back part of the swim bladder works like an ear drum and, again, helps transmit sound waves to the inner ear.
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The totoaba is also critically endangered and prized in China for its swim bladder used in traditional Chinese medicine, according to Ben Goldfarb for Environment 360.
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Having a swim bladder would keep the mola mola from grazing the surface and then diving to depths down to 50 meters, which it often does.
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Poor poachers still use gillnets to catch the totoaba, whose swim bladder sells for $20,3003 on average in China for traditional medicine and even as investments.
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The fish's swim bladder is dried and smuggled to China, where wealthy diners pay thousands of dollars for the delicacy, believing it to have medicinal powers.
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These nets are designed to catch the giant totoaba fish, whose swim bladder is considered a culinary delicacy in China and sold for more than $4,500 per pound.
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According to officials, Chinese demand for a fish called the totoaba, which is prized for its swim bladder in black markets, has caused the most collateral damage to the vaquita.
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The totoaba swim bladder is considered a delicacy in China, and fishing for it has continued despite a government ban imposed in the name of preventing the vaquita going extinct.
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The problem can be traced to Chinese demand for a rare swim bladder from the endangered totoaba fish, which shares the vaquita's range, in the northern tip of the Gulf of California.
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That restricted range has made this species, the world's smallest porpoise, particularly vulnerable to fishing boats wielding gill nets — many supplying illicit Asian markets for the swim bladder of an endangered fish, the totoaba.
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The poachers' bounty is an organ from the totoaba called the swim bladder, which is considered a delicacy and status symbol in China and can sell for up to $50,000 on the black market.
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Each flake of ancient paint was treated with a tiny drop of isinglass, a natural collagen obtained from the swim bladder of a sturgeon, which was applied, heated and pressed down to match the surface.
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The middle-age seafood shop owner pointed to the picture and said it would cost about $203,220 U.S. The totoaba's swim bladder is the priciest dried fish item in Sheung Wan, a neighborhood in Hong Kong.
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Banning the killer The now banned nets, known as gill nets, are designed to catch the giant totoaba fish, whose swim bladder is considered a delicacy in China and sold for more than $4,500 per pound.
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The seemingly imminent demise of the smallest porpoise in the world is being blamed on illegal fishing to meet Chinese demand for the swim bladder of the totoaba fish, which also lives in the northern Gulf of California.
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The totoaba's swim bladder is dried, smuggled across the border to California and then shipped to China, where it is considered a delicacy and sells for as much as $10,000 per kilogram, or close to $5,000 a pound.
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When the swim bladder is deformed or infected by bacteria or parasites, the goldfish loses its floatation stability - which could result in a fish floating to the top of the water, heavily leaning toward one side, or even swimming upside down.
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The report also focused on an issue I've written on periodically — how the vaquita death rate has been driven up by unrelenting Chinese demand for the dried swim bladder of the totoaba, a large endangered fish found in the same waters.
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In recent decades, the sleek, wide-eyed vaquita porpoise has been pushed to the brink of extinction by poachers pursuing another critically endangered sea creature, the totoaba, a fish whose swim bladder sells on the Chinese black market for thousands of dollars.
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To produce the croaking sound, special muscles vibrate against the swim bladder. These muscles are called sonic muscle fibres, and run horizontally along the fish's body on both sides around the swim bladder, connected to a central tendon that surrounds the swim bladder ventrally. These sonic muscle fibres are repeatedly contracted against the swim bladder to produce the croaking sound that gives drum and croaker their common name, effectively using the swim bladder as a resonating chamber. The sciaenids' large swim bladder is more expansive and branched than other species, which aids in the croaking.
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The latency of swim bladder adaptation after a change in pressure affects hearing and other possible swim bladder functions, presumably making audition more difficult. Nevertheless, the presence of the swim bladder and a relatively complex auditory apparatus allows the channel catfish to discern different sounds and tell from which directions sounds have come.
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There is also a relationship between the interossicular ligament and the swim bladder that it originated from the swim bladder diverticulum. This was shown by comparing the fiber of the ligament and the tunica externa of the swim bladder that have the same histological composition of elastin and icthyocoll (a specific type I collagen).
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When swim-up begins, glue secretion stops. The posterior swim bladder becomes inflated. During this stage, the fish is suspended in the water column, and the yolk is almost depleted. The anterior swim bladder forms.
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In fish where the swim bladder is closed, the gas content is controlled through the rete mirabilis, a network of blood vessels serving as a countercurrent gas exchanger between the swim bladder and the blood. The Chondrostei such as sturgeons also have a swim bladder, but this appears to have evolved separately: other Actinopterygii such as the bowfin and the bichir do not have one, so swim bladders appear to have arisen twice, and the teleost swim bladder is not homologous with the chondrostean one.
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Female ryukin goldfish with swim bladder disease The gas bladder of a fish Swim bladder disease, also called swim bladder disorder or flipover, is a common ailment in aquarium fish. The swim bladder is an internal gas-filled organ that contributes to the ability of a fish to control its buoyancy, and thus to stay at the current water depth without having to waste energy in swimming. A fish with swim bladder disorder can float nose down tail up, or can float to the top or sink to the bottom of the aquarium.Johnson, Erik L. and Richard E. Hess (2006) Fancy Goldfish: A Complete Guide to Care and Collecting, Weatherhill, Shambhala Publications, Inc.
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After initial feeding, median and pelvic fins develop, and the anterior swim bladder inflates.
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In other fishes, sonic muscles are used to produce sound by agitating the swim bladder.
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Most species possess a swim bladder (except in Gonorynchus). The swim bladder is usually divided into two chambers. A smaller anterior chamber is partially or completely covered by a silvery peritoneal tunic. A larger posterior chamber may be reduced or absent in some groups.
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In most other bony fishes the swim bladder is supplied with blood by the dorsal aorta.
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Other identifying features are the lateral line scale count, which numbers between 73 and 77 in the species, and the vertebrae count which is 37 to 39. The swim bladder is almost transparent and much more delicate than other members of Sillago. The specimen examined by McKay had an elongate oval shaped swim bladder with two rudimentary posterior extensions and no anterior extension. A delicate ductile process is present on the posterior ventral surface of the swim bladder.
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With the added function of the swim bladder as a resonating chamber, signals are amplified to noticeable levels.
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Like many stomiiformes, its scales and caudal skeleton are poorly ossified and it lacks a gas-filled swim bladder.
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Fish with barotrauma will have their enormously swollen swim-bladder protruding from their mouth, bulging eyeballs, and often sustain other, more subtle but still very serious injuries. Upon release, fish with barotrauma will be unable to swim or dive due to the swollen swim-bladder. The common practice has been to deflate the swim bladder by pricking it with a thin sharp object before attempting to release the fish. Emerging research100% of Jew fish landed from water 15 to 20 meters deep have life-threatening injuries.
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Its walls are very thick and elastic, with the posterior section being thicker than the front one. The roof of the front section of the swim bladder is directly attached to the backbone and the muscles which are connected to it are able to compress and contract the swim bladder. The grunting sounds created by the swim bladder are most likely made by the vibration of its walls. The sound is a deep grunting sound that can be heard for up to five meters away.
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Other distinguishing features include 69 to 76 lateral line scales and a total of 34 to 36 vertebrae. Swim bladder morphology is the most effective way to distinguish it between related species S. maculata and S. aeolus. The swim bladder has far reduced anterolateral extensions of swim bladder compared to S. maculata and differs from S. aeolus in having two extensions, not three. The western trumpeter whiting has very similar in coloration to S. aeolus and S. maculata, with only minor differences between the species.
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The cycle of diffusion continues until the concentration of oxygen in the arterial capillaries is supersaturated (larger than the concentration of oxygen in the swim bladder). At this point, the free oxygen in the arterial capillaries diffuses into the swim bladder via the gas gland.Kardong, K. (2008). Vertebrates: Comparative anatomy, function, evolution, (5th ed.).
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A teleost swim bladder The body of a teleost is denser than water, so fish must compensate for the difference or they will sink. Many teleosts have a swim bladder that adjusts their buoyancy through manipulation of gases to allow them to stay at the current water depth, or ascend or descend without having to waste energy in swimming. In the more primitive groups like some minnows, the swim bladder is open to the esophagus and doubles as a lung. It is often absent in fast-swimming fishes such as the tuna and mackerel.
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Though the color of each sex varies little, in the development of anatomy in band cusk eels there is a noticeable difference. Both have a hardened swim bladder (suggesting that perhaps females use it for sound too) but males alone have a structure called a 'rocker'. All individuals possess a modified first vertebrae that makes a wing-like shape just above the swim bladder. However, in males there is a free floating bone that curves along a modification of the third through sixth vertebrae and attaches to the swim bladder.
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Stridulation sounds are predominantly from 1000–4000 Hz, though sounds modified by the swim bladder have frequencies lower than 1000 Hz.
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Like other early ray-finned fish, Palaeoniscum had air sacs connected to the mouth, which served as a primitive swim bladder.
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A fish's swim bladder controls buoyancy by adjusting the amount of gas in the swim bladder, allowing it to achieve neutral buoyancy at different depths. When a fish's overall density becomes higher or lower than the surrounding water due to volume change of the swim bladder following ascent or descent, it can correct this difference over time by a physiological process involving controlled absorption and elimination of gases via the blood circulation, the gills, and a gland adjacent to the swim bladder. The human brain exhibits approximately neutral buoyancy as a result of its suspension in cerebrospinal fluid. The actual mass of the human brain is about 1400 grams; however, the net weight of the brain suspended in the CSF is equivalent to a mass of 25 grams.
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Other distinguishing features include 70 to 73 lateral line scales and a total of 35 vertebrae. The species has a known maximum length of over 30 cm (11.8 in) . Like all species of sillaginid, the swim bladder is the most dependable diagnostic feature. Japanese whiting have a swim bladder characterised by a single, long posterior extension which tapers to a slender point.
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To attract mates, some teleosts produce sounds, either by stridulation or by vibrating the swim bladder. In the Sciaenidae, the muscles that attached to the swim blabber cause it to oscillate rapidly, creating drumming sounds. Marine catfishes, sea horses and grunts stridulate by rubbing together skeletal parts, teeth or spines. In these fish, the swim bladder may act as a resonator.
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The anal fin has 2 spines with between 21 and 23 soft rays posterior to the spines. The lateral line scales number between 67 and 70, while there are 34 vertebrae. The swim bladder morphology is also distinctive, with three anterior extensions, the middle one projecting forward and the anterolateral ones curving backward along the swim bladder. There is a single posterior extension toward the caudal region.
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Like most hawkfishes, the flame hawkfish lacks a swim bladder. It is a percher and a bottom-dweller, living on and about coral heads and stony reefs.
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The reduced swim bladder and modified pelvic fin indicates that this species is demersal and may use the pelvic fin pads somewhat like sled runners on the substrate.
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The cycle of diffusion continues until the partial pressure of oxygen in the arterial capillaries exceeds that in the swim bladder. At this point, the dissolved oxygen in the arterial capillaries diffuses into the swim bladder via the gas gland. The rete mirabile allows for an increase in muscle temperature in regions where this network of vein and arteries is found. The fish is able to thermoregulate certain areas of its body.
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Tarpon swimming One of the unique features of Megalops is the swim bladder, which functions as a respiratory pseudo-organ. This gas structure can be used for buoyancy, as an accessory respiratory organ, or both. In Megalops, this unpaired air-holding structure arises dorsally from the posterior pharynx. Megalops uses the swim bladder as a respiratory organ and the respiratory surface is coated with blood capillaries with a thin epithelium over the top.
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Other distinguishing features include 69 to 76 lateral line scales and a total of 32 to 34 vertebrae. The species has a known maximum length of 33 cm. The swim bladder morphology is nearly identical to that of S. bassensis, shaped by a short, blunt anterior median projection with no posterior projection. Swim bladder morphology is useless for distinguishing between this species and S. bassensis, with the external colour the most reliable method.
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They also have two anal fins which can be used for identification between species. The lateral line on this species is prominent, with a hump above the pectoral fin and extends the length of the fish toward the caudal fin. Illustration of white marlin Internally, white marlin do not have a swim bladder, but instead have small, bubble-shaped chambers that act as a swim bladder. Similarly to most vertebrates, they have symmetrical gonads.
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The bloat eventually damages their liver, swim bladder, and kidneys so much that they die in 24–78 hours. Acei have bicuspid teeth like the rest of the genus Pseudotropheus.
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Like other saccopharyngiforms, these fish have large mouths and long, slender bodies with long tails that have a bioluminescent organ at the tip. The function of this organ is currently unknown. Saccopharynx ampullaceus lacks a traditional gas-filled swim bladder, presumably due to the pressures at the depths they live in. Instead, the function of the swim bladder has been replaced by lymphatic spaces that run along the spine which are filled with a gelatinous substance.
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Notothenioids display a morphology that is largely typical of other coastal perciform fishes. They are not distinguished by a single physical trait, but rather a distinctive set of morphological traits. These include the presence of three flat pectoral fin radials, nostrils located laterally on each side of the head, the lack of a swim bladder, and the presence of multiple lateral lines. Because notothenioids lack a swim bladder, the majority of species are benthic or demersal in nature.
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The inferior division of the inner ear, most prominently the utricle, is considered the primary area of hearing in most fishes. The hearing ability of the channel catfish is enhanced by the presence of the swim bladder. It is the main structure that reverberates the echo from other individuals’ sounds, as well as from sonar devices. The volume of the swim bladder changes if fish move vertically, thus is also considered to be the site of pressure sensitivity.
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Spring viraemia of carp, also known as swim bladder inflammation, is caused by Carp sprivivirus, also called Rhabdovirus carpio. It is listed as a notifiable disease under the World Organisation for Animal Health.
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Besides breathing in the normal way through its gills, the reticulated knifefish is able to breathe air at the surface of the water. For this purpose the swim bladder acts as a lung; it is an elongated structure that extends for the length of the body cavity and has finger-like side projections. This adaptation allows the fish to live in swamps where the water would otherwise be too low in oxygen content. The swim bladder can also be used to create sounds.
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This allows the transmission of vibrations to the inner ear. A fully functioning Weberian apparatus consists of the swim bladder, the Weberian ossicles, a portion of the anterior vertebral column, and some muscles and ligaments.
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The study signified that the characterization of the zebrafish swim bladder should not contain any expression fructose-1,6-bisphosphatase gene. The tissue of the swim bladder is known to be very high in glycogenic activity and lacking in gluconeogenesis, yet a predominant amount of Fbp was found to be expressed. This finding suggests that in the gas gland cell, Fbp forms an ATP-dependent metabolic futile cycle. Generation of heat is critically important for the gas gland cells to synthesize lactic acid because the process is strongly inhibited if ATP is accumulated.
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California corbina are uniformly grey in color with some iridescence and have an elongated and slightly compressed body shape in comparison to other croakers. Like all members of the genus Menticirrhus, the California corbina lacks a swim bladder and is unable to produce a croaking sound. It is believed that the loss of the swim bladder evolved to facilitate living in a turbulent environment. This species and the yellowfin croaker are the only two of the eight coastal croakers found in California waters to exhibit a single barbel on the lower jaw.
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The pelvic fins are colourless, but the pectoral fins and the outer margins of the anal fin and caudal fin are dusky. There are no scales, the lateral line is complete, and the swim bladder has two chambers.
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These bones grow to physically connect the auditory system, specifically the inner ear, to the swim bladder. The structure acts as an amplifier of sound waves that would otherwise be only slightly perceivable by the inner ear structure alone.
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The head is as long as it is broad. The adipose fin is long and rounded at the end, and is connected to the caudal fin. The dorsal and pectoral fins have spines. The swim bladder in these fish is reduced.
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Schultz, Ken. Essentials of Fishing. 2010. Published by John Wiley & Sons, Inc. Rockfish have a gland that produces and absorbs gas as needed, to expand or deflate the swim bladder, which enables the fish to move through different water depths.
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Bony fish have a swim bladder which helps them maintain a constant depth in the water column, but not a cloaca. They mostly spawn a large number of small eggs with little yolk which they broadcast into the water column.
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Other distinguishing features include 67 to 72 lateral line scales and a total of 34 vertebrae. Swim bladder morphology is the most effective way to distinguish it between related species S. maculata and S. burrus. The swim bladder has three anterolateral extensions; not four and it differs from S. maculata in lacking well developed anterolateral extensions reaching to the level of the vent. The colour of the oriental trumpeter whiting is similar to both S. burrus and S. maculata, having blotches that are like oblique bars, but the most posterior mid-lateral dark brown blotch is elongate and reaches caudal flexure.
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The swim bladder has three large anterior protrusions, the two lateral most extensions having a branch of which one lobe extends posteriorly for over half the length of the swim bladder. There is a single simple posterior projection. The ventral surface of the bladder has a narrow duct like process extending to the urogenital opening. The colour of the body is an olive-yellow dorsally, while paler on the sides and abdomen; the cheeks and part of the operculum are orange-yellow with one or two stripes of orange-yellow running along the sides of the body.
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Together, the structure interacts anteriorly with the lagenar otolith set within the skull and posteriorly with the swim bladder via the pleural rib. Postero-ventrally, it is the tripus, the os suspensorium and the third rib that interact directly with the anterior chamber of the swim bladder. The Weberian apparatus functions by transmitting auditory signals straight from the gas bladder, through the Weberian ossicles and then straight into the labyrinth structures of the inner ear. The structure essentially acts as an amplifier of sound waves that would otherwise be only slightly perceivable by the inner ear structure alone.
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The claustrum, an element in modern apparati, is noticeably absent from the Weberian apparatus of S. diasii. Only the first four vertebrae are involved in the Weberian apparatus of Santanichthys; There are no signs of involvement from the elements of the fifth vertebra unlike in modern otophysans. An important feature within the formation of the Weberian apparatus, which is a synapomorphy of the Otocephala, is the attachment of the anterior Pleural cavity(rib) to the Swim bladder. Another crucial feature is the anterior otophysic diverticula of the swim bladder and contacting the inner ear, seen in extant Clupeiformes.
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In Pogonopoma, the diverticulum is similar to a swim bladder and may be used as a hydrostatic organ; the first part of the diverticulum is greatly reduced and the second part is larger and has a smooth interior surface and less vascularized.
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It uses its swim bladder to amplify sounds. Roosterfish can reach over in length and over in weight. The weight of the average fish hooked is about . The fish is popular as a game fish, but it is considered a good eating fish.
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The western scorpionfish (Scorpaena onaria) is a fish belonging to the family Scorpaenidae. It is red in color. It grows to about 30 inches in length with large, broad pectoral fins and no swim bladder. They are found in the Pacific Ocean near Japan.
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A remedy, which can work within hours, perhaps by countering constipation, is to feed green pea to affected fish. Fish surgeons can also adjust the buoyancy of the fish by placing a stone in the swim bladder or performing a partial removal of the bladder.
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The following is the full list of the extant species in Class Chondrichthyes, or the cartilaginous fish. Members of this class have a backbone, gills, no swim bladder, jaws, and a skeleton made of cartilage, a soft, strong material as a replacement for bone.
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The pectoral fins are placed low on the sides. Its swim bladder is large. Speedy and dynamic, they are slim, with small scales. Barracudas also have two well-separated dorsal fins, a protruding lower jaw, and a large mouth with many large, sharp teeth.
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Bony fishes typically have fin rays rather than a fleshy makeup that you see in cartilaginous fishes. Often, you will also see a swim bladder within bony fishes which acts as a floatation tool, allowing the fish to adjust its depth in the water.
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As the fish begins its life as an embryo, its cement glands begin to develop. As a non feeding larva, glue is secreted from the cement glands and the posterior swim bladder forms. The gills, mouth, and gut lining form. The yolk sac becomes streamlined.
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Barotrauma injury to tiger angelfish – head end. Note distended swim bladder and gas space in abdominal cavity Barotrauma injury to tiger angelfish – tail end Fish with isolated swim bladders are susceptible to barotrauma of ascent when brought to the surface by fishing. The swim bladder is an organ of buoyancy control which is filled with gas extracted from solution in the blood, and which is normally removed by the reverse process. If the fish is brought upwards in the water column faster than the gas can be resorbed, the gas will expand until the bladder is stretched to its elastic limit, and may rupture.
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It is the largest of the Sillaginid fishes with 129 to 147 lateral line scales, and like all fishes in the family is best distinguished by the shape of its swim bladder. In plan view, the swim bladder has a land slug-like appearance, with a posteriorly tapering extension and two anterolateral extensions or ‘horns’. There are no duct-like processes on the ventral surface unlike taxa in the genus Sillago. In situations where identification is needed quickly, the colour of the King George whiting is also very distinctive, with a pale golden brown to olive brown top colour and white to silver colour on its underside.
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This fish reaches up to 43 to 47 centimeters long. It is reddish brown in color with many brown and black spots, especially on the fins. The head is spiny. It does not have a swim bladder; it spends most of its time on the ocean floor.
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A review of the holotype by McKay led to the correct identification, with the author noting that the swim bladder morphology and vertebrae count were beyond any variation in S. japonica. The name is derived from 'Asiaticus', meaning Asiatic, which is also reflected in the species' common name.
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The spinous dorsal fin is situated above the pelvis. The hind end of the caudal fin is forked or concave, and it is set at the end of a stout peduncle. The pectoral fins are placed low down on the sides. The barracuda has a large swim bladder.
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Its diet includes small fish and crustaceans. It has been recorded at up to in length and weighing up to . A tarpon is capable of filling its swim bladder with air, like a primitive lung. This gives it a predatory advantage when oxygen levels in the water are low.
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Yunnanilus longibulla is a species of ray-finned fish, a stone loach, in the genus Yunnanilus. The type locality for this species is Chenghai Lake in Yunnan. The specific name longibulla means "long bubble" and refers to the elongated shape of the swim bladder compared to closely related species.
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The pectoral fin has 11 or 12 soft rays, the pelvic fin 6 and the anal fin 13. There are several short post-abdominal spines. The swim bladder is gas-filled and well-developed. This fish has a dark-coloured back and silvery sides, with darker pigment along the lateral line.
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Anglers let big cash bonanza get away. Retrieved 18 May 2019. The fishing is prompted by the value placed on the swim bladders of this fish for use in traditional Chinese medicine. In some markets, notably the Chinese markets, a good specimen swim bladder fetches more than its weight in gold.
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They reach a maximum of 3 inches. They are found closer to the surface because they retain a swim bladder. Their diet consists of small invertebrates such as mayfly nymphs and blackfly larvae. They have been observed feeding off submerged surfaces and strategically waiting for food to get washed downstream.
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Crawford, R. H. 1974. Structure of an air-breathing organ and the swim bladder in the Alaska Blackfish, Dallia Pectoralis Bean. Canadian Journal of Zoology 52(10):1221-1225. www.nrcresearchpress.com/doi/pdf/10.1139/z74-162. Specifically, the esophagus of a blackfish can be subdivided into a non- respiratory and a respiratory section.
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Remoras sometimes attach to small boats. They swim well on their own, with a sinuous, or curved, motion. When the remora reaches about , the disc is fully formed and the remora can then attach to other animals. The remora's lower jaw projects beyond the upper, and the animal lacks a swim bladder.
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The cypriniformes (family Cyprinidae) are traditionally grouped with the Characiformes, Siluriformes, and Gymnotiformes to create the superorder Ostariophysi, since these groups share some common features. These features include being found predominantly in fresh water and possessing Weberian ossicles, an anatomical structure derived from the first five anterior-most vertebrae, and their corresponding ribs and neural crests. The third anterior-most pair of ribs is in contact with the extension of the labyrinth and the posterior with the swim bladder. The function is poorly understood, but this structure is presumed to take part in the transmission of vibrations from the swim bladder to the labyrinth and in the perception of sound, which would explain why the Ostariophysi have such a great capacity for hearing.
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The anal fin has 2 spines followed by 14 to 17 soft rays. Over the distribution of the species, the vertebrae number differs, with fish in Western Australia having 33 and those in south east Queensland having one or two additional modified vertebrae. Also varying over the range is the lateral line scale count, with Western Australian fish having less than Queensland fish, with the range for the species between 54 and 61 scales. The swim bladder of the species is very similar and in some cases indistinguishable from a related species, Sillago ciliata, with the anterior part of the swim bladder having rudimentary tubules projecting anteriorly and a lateral series of tubules that diminishes in size and become sawtooth-like, projecting posteriorly.
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The bonefishes' closest relatives are the tarpons and ladyfishes in the order Elopiformes. Bonefishes are unlike tarpons in that their mouths are under the snout rather than the end of it. Like tarpons and ladyfishes, bonefishes can breathe air via a modified swim bladder and are found in brackish waters. Bonefish larvae are leptocephalic.
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The lung/swim bladder originated as an outgrowth of the gut, forming a gas-filled bladder above the digestive system. In its primitive form, the air bladder was open to the alimentary canal, a condition called physostome and still found in many fish. The primary function is not entirely certain. One consideration is buoyancy.
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Freshwater butterfly fish are small, no more than in length, with very large pectoral fins. It has a large and well-vascularized swim bladder, enabling it to breathe air at the surface of the water. It is carnivorous, feeding primarily on aquatic insects and smaller fishes. The freshwater butterflyfish is a specialized surface hunter.
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Some evidence indicates sound production in hardhead catfish is differentiated both mechanistically and contextually. Mechanistically, sound can be produced in different ways. Thin bones by the swim bladder can be vibrated by specialized sonic muscles. Also, grinding of the pharyngeal teeth and rubbing of the pectoral spines against the pectoral girdle can produce sound.
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Fish sense sounds in a variety of ways, using the lateral line, the swim bladder, and in some species the Weberian apparatus. Fish orient themselves using landmarks, and may use mental maps based on multiple landmarks or symbols. Experiments with mazes show that fish possess the spatial memory needed to make such a mental map.
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Gar and bowfin have a vascularized swim bladder that functions in the same way. Loaches, trahiras, and many catfish breathe by passing air through the gut. Mudskippers breathe by absorbing oxygen across the skin (similar to frogs). A number of fish have evolved so- called accessory breathing organs that extract oxygen from the air.
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They should be kept in a species-only tank with other goldfish. It is advised to feed goldfish only sinking food because flakes can cause swim bladder issues. Lionhead goldfish are omnivores so they thrive on a diet rich in plant and animal matter. High-protein diets will make their colors more vibrant and will cause greater growth.
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High lipid content and porous bones result in an almost neutral buoyancySideleva, V.G. (1996). Comparative character of the deep-water and inshore cottoid fishes endemic to Lake Baikal. Journal of Fish Biology 49(sA): 192–206. and lack of swim bladder allows the fish to tolerate varying pressure extremes as they move through the water column.
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Sand tiger sharks store air in their stomachs, using it as a form of swim bladder. Bottom-dwelling sharks, like the nurse shark, have negative buoyancy, allowing them to rest on the ocean floor. Some sharks, if inverted or stroked on the nose, enter a natural state of tonic immobility. Researchers use this condition to handle sharks safely.
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Snakes sense infrasound through their jaws, and baleen whales, giraffes, dolphins and elephants use it for communication. Some fish have the ability to hear more sensitively due to a well-developed, bony connection between the ear and their swim bladder. This "aid to the deaf" for fishes appears in some species such as carp and herring.
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Other distinguishing features include 68 to 70 lateral line scales and a total of 34 vertebrae. The species has a known maximum length of 17 cm, and possibly longer. The swim bladder is quite distinct, having a bifurcate anterior extensions, while the anterolateral extensions are recurved and extend to the ventral duct. There is a single posterior extension.
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They lack a swim bladder. The lateral line of clingfish is well developed, but may not extend to the posterior parts of the body. The skin of clingfishes is smooth and scaleless, with a thick layer of protective mucus. In at least Diademichthys lineatus and Lepadichthys frenatus, the mucus production increases if the fish is disturbed.
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The family name Rachycentridae, from the Greek words rhachis ("spine") and kentron ("sting"), was inspired by these dorsal spines. The mature cobia has a forked, slightly lunated tail, which is usually dark brown. The fish lacks a swim bladder. The juvenile cobia is patterned with conspicuous bands of black and white and has a rounded tail.
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Its swim bladder, unlike most fishes, is divided into two parts. The right side is rather larger, and can function as a breathing organ if needed. Therefore, P. teugelsi can survive for some time out of water (if it is kept moist) through breathing air. In addition, P. teugelsi have gills that resemble those of young amphibians.
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N. coriiceps members have scales that typically appear brown or gray in color. Its teeth consist of a multi-row tooth plate and caniform teeth, which are located in the outer portion of the jaw. Adults males typically reach a length of approximately 50 cm (20 in). Like many other notothenioid fishes, it lacks a swim bladder.
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The dermis is covered with separate dermal placoid scales. They have a cloaca into which the urinary and genital passages open, but not a swim bladder. Cartilaginous fish produce a small number of large, yolky eggs. Some species are ovoviviparous and the young develop internally but others are oviparous and the larvae develop externally in egg cases.
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For example, the skeleton is only partially calcified, and the muscles and gills are underdeveloped. The eyes, nasal organ and lateral line are also reduced, and they lack a swim bladder. The aphyonids are viviparous, giving birth to live young. The males bundle their sperm into small sacs (spermatophores), so that they can be stored for extended periods.
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Clupeiformes consists of 350 living species of herring and herring-like fishes. This group is characterised by an unusual abdominal scute and a different arrangement of the hypurals. In most species, the swim bladder extends to the braincase and plays a role in hearing. Ostariophysi, which includes most freshwater fishes, includes species that have developed some unique adaptations.
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Fins also increase the tail's surface area, increasing speed. The streamlined body of the fish decreases the amount of friction from the water. Since body tissue is denser than water, fish must compensate for the difference or they will sink. Many bony fish have an internal organ called a swim bladder that adjusts their buoyancy through manipulation of gases.
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Notothenia is a genus of notothenid fish. They are native to the Southern Ocean and other waters around Antarctica. These fish have some adaptations that allow them to thrive in such inhospitable habitat, like antifreeze proteins in their blood and ample fat to insulate them against heat loss and to offset their lack of a swim bladder.
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When there is not enough oxygen in the river or lake, tambaqui obtain oxygen from the air. They are able to do this by their physical and inner body parts, such as their gills and swim bladder vascularization. Tambaqui is a fish that lives in freshwater. Juveniles can survive in brackish water when the salinity is gradually raised.
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By changing the amount of gas in these swim bladders, fish actively control their density. If they increase the amount of air in their swim bladder, their overall density will become less than the surrounding water, and increased upward buoyancy pressures will cause the fish to rise until they reach a depth at which they are again at equilibrium with the surrounding water.
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If they increase the amount of air in their swim bladder, their overall density will become less than the surrounding water, and increased upward buoyancy pressures will cause the fish to rise until they reach a depth at which they are again at equilibrium with the surrounding water. In this way, fish behave essentially as a hot air balloon does in air.
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The heavy scale armour of the early bony fishes would certainly weigh the animals down. In cartilaginous fishes, lacking a swim bladder, the open sea sharks need to swim constantly to avoid sinking into the depths, the pectoral fins providing lift. Another factor is oxygen consumption. Ambient oxygen was relatively low in the early Devonian, possibly about half of modern values.
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Flatfishes lay eggs that hatch into larvae resembling typical, symmetrical, fish. These are initially elongated, but quickly develop into a more rounded form. The larvae typically have protective spines on the head, over the gills, and in the pelvic and pectoral fins. They also possess a swim bladder, and do not dwell on the bottom, instead dispersing from their hatching grounds as plankton.
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The mouth is set low and is usually inferior. Their croaking mechanism involves the beating of abdominal muscles against the swim bladder. Sciaenids are found worldwide, in both fresh and salt water, and are typically benthic carnivores, feeding on invertebrates and smaller fish. They are small to medium-sized, bottom-dwelling fishes living primarily in estuaries, bays, and muddy river banks.
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The posterior part of the upper jaw has numerous pointed, cardiform teeth arranged in rows, but no large fangs or gaps occur between groups of teeth. The eyes are well developed, although these fish mainly live in darkness. The swim bladder lies below the 9th and 10th vertebrae and has two chambers. The precaudal vertebrae are 15 to 17 in number.
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Pressure detection uses the organ of Weber, a system consisting of three appendages of vertebrae transferring changes in shape of the gas bladder to the middle ear. It can be used to regulate the buoyancy of the fish. Fish like the weather fish and other loaches are also known to respond to low pressure areas but they lack a swim bladder.
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When the remora reaches about , the disc is fully formed and the remora can then attach to other animals. The remora's lower jaw projects beyond the upper, and the animal lacks a swim bladder. Some remoras associate with specific host species. They are commonly found attached to sharks, manta rays, whales, turtles, and dugongs, hence the common names "sharksucker" and "whalesucker".
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Notopterids have specialized swim bladders. The organ extends throughout the body and even into the fins in some cases. Although the swim bladder is not highly vascularised, it can absorb oxygen from air and also functions to produce sound by squeezing air through a narrow passage into the pharynx. At least some species prepare nests and guard the eggs until they hatch.
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This goby has a thin, elongated, "eel-like" body up to 13 centimeters (5.1in) in length. It exhibits neoteny, retaining a larval form even when a sexually mature adult. It lacks scales and has a swim bladder and a small pelvic fin; most gobies develop scales, lose their swim bladders, and grow longer pelvic fins as they mature into adulthood.
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The head is small and lizard-like with a large gaping mouth and small eyes on either side. Since its eyesight is poor the bichir primarily hunts by smell. External nostrils protrude from the nose of the fish to enable this. The fish has a pair of primitive lungs instead of a swim bladder, allowing it to periodically gulp air from the surface of the water.
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The caudal fin is forked with short, although distinct, peduncle flanges. The anal fin is longer than the dorsal fin and begins well posterior to the dorsal fin base. Pectoral fins are long and slender. The fish has a large, clearly visible swim bladder located below the spine just forward of the longitudinal mid-point, and an adipose fin on the dorsal surface above the anal fin.
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The details of this jaw anatomy vary between species, and help distinguish the different elasmobranch clades. The pelvic fins in males are modified to create claspers for the transfer of sperm. There is no swim bladder; instead, these fish maintain buoyancy with large livers rich in oil. The earliest elasmobranch fossils came from the Devonian and many surviving orders date back to the Cretaceous, or even earlier.
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Other distinguishing features include 67 to 70 lateral line scales and a total of 34 vertebrae. The species has a known maximum length of 20 cm. The swim bladder has two anterior extensions which extend forward and diverge before terminating above the auditory capsule. Two lateral extensions commence anteriorly, sending tubules to the anterior and extending below the abdominal wall adjacent to the swimbladder.
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The little tunny has some anatomical variations when compared to other species of Euthynnus. E. alletteratus lacks a swim bladder, like most other tuna, so it must constantly keep moving to stay afloat. The pectoral fins are crucial to the little tunny in maintaining its position in the water column. Its liver is very disproportionate, with the right lobe much longer than the left or middle lobes.
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Other distinguishing features include 67 to 72 lateral line scales and a total of 33 to 35 vertebrae. The species has a known maximum length of over 16 cm. The swim bladder is similar to the Japanese whiting, characterised by a short central anterior extension with two anteriorly facing anterolateral projections, which may be well or poorly developed. There is a single median posterior extension.
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A typical clupeid, this is a small silver fish with a brighter stripe down the lateral line, a broad snout with tapering sides. It has a relatively large swim bladder which allows it to travel large vertical distances in the water column. The maximum length is 17 cm, but most specimens are about 10 cm long and they are thought to be sexually mature at 6.8 cm.
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One is the Weberian apparatus, an arrangement of bones (Weberian ossicles) connecting the swim bladder to the inner ear. This enhances their hearing, as sound waves make the bladder vibrate, and the bones transport the vibrations to the inner ear. They also have a chemical alarm system; when a fish is injured, the warning substance gets in the water, alarming nearby fish.Helfman, Collete, Facey and Bowen pp.
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The hingemouth (Phractolaemus ansorgii) is a small freshwater fish that is found only in west central Africa, the sole member of the family Phractolaemidae. The mouth can extend like a small trunk, thus the name, and has just two teeth, both in the lower jaw. The swim bladder has two compartments, and can function as a lung, allowing the hingemouth to survive in oxygen-poor environments.
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Their bodies tend to be dorso-ventrally flattened, and they usually have five pairs of gill slits and a large mouth set on the underside of the head. The dermis is covered with separate dermal placoid scales. They have a cloaca into which the urinary and genital passages open, but not a swim bladder. Cartilaginous fish produce a small number of large yolky eggs.
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Atractoscion is a genus of fish in the family Sciaenidae found in the Atlantic, Indian and Pacific Ocean. The genus is distinguished by having a lower jaw that protrudes beyond the upper jaw, shape and position of the swim bladder, the lack of barbels and sensory pores on the chin, teeth that are cardiform or pluriserial, and caudal fin that is slightly emarginate to lunate.
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In the channel catfish, sounds are produced only by pectoral stridulation, as this species does not express sonic muscles. However, the swim bladder may still be used to help with audition. Due to the high density of water, sound travels 4.8 times faster and over longer distances under water than in air. Consequently, sound production via stridulation is an excellent means of underwater communication for channel catfish.
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In appearance, it is like the Atlantic tarpon, Megalops atlanticus: olive-green on top, and silver on the sides. The large mouth is turned upwards; the lower jaw contains an elongated, bony plate. The last ray of the dorsal fin is much longer than the others, reaching nearly to the tail. It is capable of filling its swim bladder with air and absorbing oxygen from it.
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This results in the Hb-O2 dissociation curve being shifted downward and not just to the right. At low pH, hemoglobins showing the Root effect don't become fully oxygenated even at oxygen tensions up to 20kPa. This effect allows hemoglobin in fish with swim bladders to unload oxygen into the swim bladder against a high oxygen gradient.Verde, C., A. Vergara, D. Giordano, L. Mazzarella, and G. di Prisco. 2007.
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The amount of vertebrae are also diagnostic, having 34 in total. The swim bladder is the most accurate diagnostic feature, having two posterior extensions and two anterior extensions. The two anterior extensions extend forward and diverge to end on each side of the basioccipital above the auditory capsule. Two lateral extensions also commence anteriorly, each of them sending a blind tubule anterolaterally and then extending along the abdominal wall.
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Modern fishes with such a tail are rarely quick swimmers, and the cephalaspidomorphi were not likely very active animals. They probably spent much of their time semi-submerged in the mud. They also lacked a swim bladder, and would not have been able to keep afloat without actively swimming. The head shield provided some lift though, and would have made the cephalaspidomorphi better swimmers than most of their contemporaries.
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The respiratory section can be identified by its extensive mucosal folding and vascularization, as well as widespread capillaries throughout the epithelium. This respiratory structure implies selection pressures for the development of a purely respiratory organ and a purely hydrostatic organ. The interesting factor is the retention of the hydrostatic swim bladder, which seems unnecessary unless it is important in maintaining neutral buoyancy in the cold winter months under ice cover.
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Elacatinus colini are born with a fully functional mouth, inflated swim bladder, pigmented eyes, and two visible otoliths. After about 18–20 days post hatch (dph), fin folds are completely gone, and the pelvic and dorsal fins begin to form. At around 20–28 dph, the pelvic fin elongates but remains unfused. Pre-settled larvae have elongated snouts, partially fused pelvic fins, and exhibit the first dorsal fin.
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There are also two posterior extensions which project into the post-coelomic region. The morphology of the swim-bladder is quite similar to S. sihama, but the tubules are very simple, unlike S. sihama which has complexly folded extensions. The Thai whiting is a pale silvery colour, being darker on top and lighter below. The top of the snout is blackish, while the opercle, preopercle and preorbital are bright silver.
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Its head is small with the protrusible jaw typical of lampriformes; it has 40 to 58 gill rakers, and no teeth. The organs of the giant oarfish are concentrated toward the head end of the body, possibly enabling it to survive losing large portions of its tail. It has no swim bladder. The liver of R. glesne is orange or red, the likely result of astaxanthin in its diet.
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The length of the planktonic stage varies between different types of flatfishes, but eventually they begin to metamorphose into the adult form. One of the eyes migrates across the top of the head and onto the other side of the body, leaving the fish blind on one side. The larva also loses its swim bladder and spines, and sinks to the bottom, laying its blind side on the underlying surface.
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Other distinguishing features include 66 to 70 lateral line scales and a total of 33 vertebrae. The species has a known maximum length of 20 cm. The swim bladder has a short anterior extension, which is significantly longer in older individuals, while there are also 5 short, pointed anterolateral projections. There is a single, poorly developed posterior projection and a poorly developed duct like process on the ventral surface.
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The Moridae are a family of cod-like fishes, known as codlings, hakelings, and moras. Morids are marine fishes found throughout the world, and may be found at depths to , although most prefer shallower waters. In appearance, they greatly resemble the typical cods, from which can only be distinguished by their skeletal features and the structure of the swim bladder. They grow up to long (red codling, Pseudophycis bachus).
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Fish food should ideally provide the fish with fat (for energy) and amino acids (building blocks of proteins) and the fish food (whether flake or pellet) must be speedily digested in order to prevent buildup of intestinal gas, kidney failure and infections (such as swim bladder problems and dropsy) and to avoid aquarium pollution due to excessive ammonia. Aquatic diets for carnivores must contain vegetable matter such as spirulina.
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In some fish, a rete mirabile fills the swim bladder with oxygen. A countercurrent exchange system is utilized between the venous and arterial capillaries. By lowering the pH levels in the venous capillaries, oxygen unbinds from blood hemoglobin. This causes an increase in venous blood oxygen concentration, allowing the oxygen to diffuse through the capillary membrane and into the arterial capillaries, where oxygen is still sequestered to hemoglobin.
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Sciaena umbra juvenile It is a rather nocturnal fish but it can occasionally be found during the day among beds of sea grass and on rocky bottoms in the vicinity of caves or large crevices where it can shelter. This species is social and lives in small groups. It feeds off the small fishes and crustaceans. They are capable of creating sound using some muscles under their well developed swim bladder.
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Alligator gar have gills, but unlike other species of fish, with few exceptions, they also have a highly vascularized swim bladder lung that supplements gill respiration. The bladder not only provides buoyancy, but also enables them to breathe in air, which is why they are able to inhabit bodies of water in which most other fishes would die of suffocation. The swim bladder is connected to their fore gut by a small pneumatic duct, which allows them to breathe or gulp air when they break the surface, an action seen quite frequently on lakes in the Southern United States during the hot summer. The scales of alligator gar are not like the scales of other fishes, which have flexible elasmoid scales; their bodies are protected by inflexible and articulated ganoid scales that are rhomboidal-shaped, often with serrated edges, and composed of a tough inner layer of bone and hard outer layer of ganoin, which is essentially homologous to tooth enamel, making them nearly impenetrable.
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This developed, in later species, into the lung and (later) the swim bladder, used to keep the fish at neutral buoyancy. Acanthodians share with Actinopterygii the characteristic of three otoliths, the sagitta in the sacculus, the asteriscus in the lagena, and the lapillus in the utriculus. In dipnoans there are only two otoliths and in Latimeria there is only one. However, most of the above synapomorphies can ultimately be found in several chondrychthyian groups.
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The swim bladder contains several branched appendages which are vibrated to make a grunting sound which can be heard from up to 30m away and this grunting is produced by the males during the spawning season. Body colour pearly-silver, with bronze traits dorsally. The fin bases are reddish brown and mouth cavity yellow-gold or salmon pink. The scales are large and every fourth scale is set at a different angle from the rest.
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Typical Type I male calls are divided into short grunts that last for milliseconds or are produced in a series of grunts called a "grunt train", mid-duration growls, and long duration advertisement hums that can last up to an hour. These calls can be recorded naturally. They can also be produced in a laboratory, a procedure known as "fictive calling". In nature, two muscles contracting on the swim bladder produce these sounds.
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The swim bladder is absent. The largest species, the 90-cm (3-ft) long abyssal halosaur (Halosauropsis macrochir) is also one of the most deep-living fish, recorded at depths of 3,300 m (11,000 ft). Halosaurs have developed certain adaptations to life at these extreme depths, where no light penetrates. Their lateral line system enabling the detection of vibrations in the water is highly developed; the pores run the length of the fish's body.
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In some fish, a rete mirabile fills the swim bladder with oxygen, increasing the fish's buoyancy. A countercurrent exchange system is utilized between the venous and arterial capillaries. Lowering the pH levels in the venous capillaries causes oxygen to unbind from blood hemoglobin. This causes an increase in venous blood oxygen partial pressure, allowing the oxygen to diffuse through the capillary membrane and into the arterial capillaries, where oxygen is still sequestered to hemoglobin.
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The posterior extension is a single, tapering projection that extends well into the caudal region. A duct like process extends from the ventral surface to the urogenital opening. Swim bladder morphology is useless when determining between S. ciliata and S. analis, as they are nearly identical. The body is a pale brown or silvery brown colour, transitioning to white below, with green, mauve and rosy reflections when the fish is first removed from the water.
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While most of these were open-water fishes, one group, the Elpistostegalians, adapted to life in the shallows. They evolved flat bodies for movement in very shallow water, and the pectoral and pelvic fins took over as the main propulsion organs. Most median fins disappeared, leaving only a protocercal tailfin. Since the shallows were subject to occasional oxygen deficiency, the ability to breathe atmospheric air with the swim bladder became increasingly important.
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Bullhead are predators that will eat prawns, molluscs and small fish such as gobies and blennies. Despite their small size they are aggressive and will attack fish bigger than themselves. They lie in wait for prey, camouflaged against rocks and weed before striking out at anything that passes. Like all fish in the family Cottidae, the bullhead does not have a swim bladder, meaning that it sinks as soon as it stops swimming.
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The family arguably also contains the "Sundasalangidae", a paedomorphic taxon first thought to be a distinct salmoniform family, but then discovered to be deeply nested in the Clupeidae. In the fossil record, clupeids date back to the early Paleogene. Clupeids spawn huge numbers of eggs (up to 200,000 in some species) near the surface of the water. After hatching, the larvae live among the plankton until they develop a swim bladder and transform into adults.
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Larvae and immatures inhabit the upper water layers, down to some dozen metres; larvae before notochord flexion/metamorphosis in particular can sometimes be found right at the surface. As opposed to adults, they still have a small swim bladder. Young whalefish make nightly vertical migrations into the lower mesopelagic zone to feed on copepods. When males make the transition to adults, they develop a massive liver, and then their jaws fuse shut.
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Shortnose sturgeon are cartilaginous with bones only in the skull, jaw and pectoral girdle. It is a physostome fish, so its swim bladder is connected to the intestinal tract by a special duct. This duct allows for gas pressure regulation through swallowing air or releasing air through the gut. The intestines for shortnose sturgeon are dark and have a spiral valve (important for nutrient absorption), similar to that of sharks and rays.
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The buccal cavity of the electric eel may breathe air. Catfish of the families Loricariidae, Callichthyidae, and Scoloplacidae absorb air through their digestive tracts. Lungfish, with the exception of the Australian lungfish, and bichirs have paired lungs similar to those of tetrapods and must surface to gulp fresh air through the mouth and pass spent air out through the gills. Gar and bowfin have a vascularized swim bladder that functions in the same way.
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Synodontis schall has a shield on its body and has strong bony spines on the pectoral and dorsal fins. Some areas of new evolutionary forces have allowed for the Synodontis schall to have different phenotypes. Recent studies have found evidence for an increase number of teeth and gill rakers which could possibly point to a change from them being herbivores to carnivores. The swim bladder of Synodontis schall is whitish in appearance.
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The liver's effectiveness is limited, so sharks employ dynamic lift to maintain depth when not swimming. Sand tiger sharks store air in their stomachs, using it as a form of swim bladder. Most sharks need to constantly swim in order to breathe and cannot sleep very long without sinking (if at all). However, certain species, like the nurse shark, are capable of pumping water across their gills, allowing them to rest on the ocean bottom.
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The species name silneus is a reference to Silenus, a figure in Greek mythology. The distinctive head of the prowfish also features a number of sensory pores made all the more obvious by fringes of blue or white. Prowfish have small ctenoid scales and a variable coloration; typically, they are bluish-grey to olive brown with small dark spots, grading to lighter shades ventrally. The lateral line and swim bladder are absent.
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The anal fin is similar to the second dorsal fin with 2 spines followed by 22 to 24 soft rays. The species has 75 to 80 lateral line scales and a total of 38 to 40 vertebrae, also diagnostic features. The species is one of the smaller whitings, growing only to a maximum length of 15 cm overall. The swim bladder of S. arabica has no anterior extensions and a single posterior extension.
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However, acoustic technology has been one of the most important driving forces behind the development of the modern commercial fisheries. Sound waves travel differently through fish than through water because a fish's air-filled swim bladder has a different density than seawater. This density difference allows the detection of schools of fish by using reflected sound. Acoustic technology is especially well suited for underwater applications since sound travels farther and faster underwater than in air.
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In 2004 a film crew shooting footage for a new documentary on the heavy water sabotage became aware of an unusual fish, swimming near the lake bottom at a depth of 430 m. Two specimens of the previously unknown fish were captured in April 2005. Analysis revealed the fish to be closely related to Arctic char. The light-colored, translucent fish is up to 15 cm long and lacks a swim bladder.
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Since the chamber is filled with liquid, it has the advantage over a swim bladder of not changing significantly in volume with pressure. Glass squids in the family Cranchiidae for example, have an enormous transparent coelom containing ammonium ions and occupying about two-thirds the volume of the animal, allowing it to float at the required depth. About half of the 28 families of squid use this mechanism to solve their buoyancy issues.
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The swim bladder has elongate posterior chambers, two chambers in Malapterurus and three in Paradoxoglanis. Malapterurus have been conditioned by means of reward to discharge on signal. As reported in the New York Times, April 2, 1967, a researcher, Dr. Frank J. Mandriota of City College, New York, conditioned an M. electricus to discharge on a light signal for a reward of live worms delivered automatically. This is the first conditioning that modified neither glandular nor muscular responses.
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The slender whiting (Sillago attenuate) is a poorly known species of inshore marine fish of the smelt whiting family, Sillaginidae that has a distribution limited to the Persian Gulf only. The Slender whiting, like most sillaginids requires careful study to determine its identity, with ray and vertebrae counts as well as swim bladder morphology distinguishing features. This inshore species of fish is commonly taken by fishermen using beach seines and is sold fresh in local markets.
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Static image of a sonar scan. The backscattered signal (green) above the bottom is likely the deep scattering layer. The swim bladder (marked here as S and S') of Alburnoides bipunctatus. The swim bladders of large numbers of mesopelagic fishes cause sonar waves to be reflected in a recognisable layer The deep scattering layer, sometimes referred to as the sound scattering layer, is a name given to a layer in the ocean consisting of a variety of marine animals.
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Coelacanth also possess a unique rostral organ within the ethmoid region of the braincase. Also unique to extant coelacanths is the presence of a "fatty lung" or a fat-filled single-lobed vestigial lung, homologous to other fishes' swim bladder. The parallel development of a fatty organ for buoyancy control suggests a unique specialization for deep-water habitats. There are small, hard but flexible plates around the vestigial lung in an adult specimen, though not around the fatty organ.
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When a rockfish is caught at depths of 60 feet or more and pulled to the surface, the swim bladder cannot adjust quickly to the change in water pressure and overfills with air – pushing the fish's stomach out of its mouth and causing damage to other organs.Brochure produced by Sea Grant on rockfish barotrauma This does not affect the eating quality of the fish; however, significant numbers of rockfish inadvertently caught with other species are wasted in this manner.
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The slimy sculpin is a nocturnal fish that usually spends most of its time on the stream bottom and seeks shelter under rocks and logs, especially during spawning season. When it swims, it sometimes appears to be "hopping" along the bottom because of its inefficient ability to swim. This is partly due to the absence of a swim bladder, which normally gives buoyancy to a fish. The fish has been studied in waters where there is current freshwater acidification.
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Deep-water teleosts, which do not have a swim bladder, have few lipids and proteins, deeply ossified bones, and watery tissues that maintain their buoyancy. Some sharks' livers are composed of low- density lipids, such as hydrocarbon squalene or wax esters (also found in Myctophidae without swim bladders), which provide buoyancy. Swimming animals that are denser than water must generate lift or adapt a benthic lifestyle. Movement of the fish to generate hydrodynamic lift is necessary to prevent sinking.
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They can be found both in brackish and marine waters. The adults can be found either in groups of 5-50 fish or as solitary fish. They have been recorded producing thumping sounds when under stress, this is done by vibrating the swim bladder using muscular contractions. The adults are predators on fishes (including smaller conspecifics), crabs, shrimps, and cephalopods while the smaller juveniles prey on crustaceans within the beds of sea grass in shallow waters.
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1962; 4th ed. 1970) The aortic arches then merge above the gills to form a dorsal aorta supplying the body with oxygenated blood. In lungfishes, bowfin and bichirs, the swim bladder is supplied with blood by paired pulmonary arteries branching off from the hindmost (6th) aortic arch. The same basic pattern is found in the lungfish Protopterus and in terrestrial salamanders, and was probably the pattern found in the tetrapods' immediate ancestors as well as the first tetrapods.
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He utters long strings of grunts and growls while fighting, but his courtship call is more of a prolonged hum. He may produce this sound for over an hour at a time, reaching frequencies near 100 Hz. When a male makes the sound, gravid females respond by moving toward him. The fish produces the sound using the muscles of its modified swim bladder. It receives the sound in its saccule, a sensory organ in the inner ear.
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Atlantic croaker in Pass Christian, Mississippi The name croaker is descriptive of the noise the fish makes by vibrating strong muscles against its swim bladder, which acts as a resonating chamber much like a ball. The Atlantic croaker is the loudest of the drum family. The fish is also referred to as a hardhead, with smaller ones called pin heads. During spawning season (August to October), croakers turn a deep golden color, from this comes the name golden croaker.
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This allows the transmission of vibrations to the inner ear. In anotophysians, the three first vertebrae are specialized and associated with one or more cephalic ribs (a primitive Weberian apparatus). In the otophysians, a distinct modification of the anterior four or five first vertebrae is found, as well as the Weberian ossicles. The fully functioning Weberian apparatus consists of the swim bladder, the Weberian ossicles, a portion of the anterior vertebral column, and some muscles and ligaments.
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The bony fish lineage shows more derived anatomical traits, often with major evolutionary changes from the features of ancient fish. They have a bony skeleton, are generally laterally flattened, have five pairs of gills protected by an operculum, and a mouth at or near the tip of the snout. The dermis is covered with overlapping scales. Bony fish have a swim bladder which helps them maintain a constant depth in the water column, but not a cloaca.
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Some fish species create noise by engaging specialized muscles that contract and cause swimbladder vibrations. Oyster toadfish produce loud grunting sounds by contracting muscles located along the sides of their swim bladder, known as sonic muscles Female and male toadfishes emit short-duration grunts, often as a fright response. In addition to short-duration grunts, male toadfishes produce “boat whistle calls”. These calls are longer in duration, lower in frequency, and are primarily used to attract mates.
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Roche's snake blenny (Ophidion rochei) is a fish species in the genus Ophidion and the family Ophidiidae. Widespread in the Mediterranean Sea in western and northern regions, also in the Black Sea, Sea of Marmara and it has been recorded in the Atlantic. Marine subtropical demersal fish, up to long. The specific name honours the Swiss physician and naturalist François-Etienne Delaroche (1780-1813), who wrote about the distinctive swim-bladder anatomy of Ophidion barbatum in 1809.
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The roosterfish, Nematistius pectoralis, is a game fish found in the warmer waters of the East Pacific from Baja California to Peru. It is the only species in the genus Nematistius and the family Nematistiidae. It is distinguished by its "rooster comb", seven very long spines of the dorsal fin. The roosterfish has an unusual arrangement of its ears: the swim bladder penetrates the brain through the large foramina and makes contact with the inner ear.
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Catfish of the families Loricariidae, Callichthyidae, and Scoloplacidae absorb air through their digestive tracts. Lungfish, with the exception of the Australian lungfish, and bichirs have paired lungs similar to those of tetrapods and must surface to gulp fresh air through the mouth and pass spent air out through the gills. Gar and bowfin have a vascularized swim bladder that functions in the same way. Loaches, trahiras, and many catfish breathe by passing air through the gut.
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P. senegalus is smaller than other bichirs, reaching about 35.5 cm (14 in). The fish has a pair of primitive lungs instead of a swim bladder, allowing it to periodically gulp air from the surface of the water. In the aquarium, bichirs can be observed dashing to the surface for this purpose. This bichir's skin serves as a particularly effective armor, and has been studied as a model for personal armor for better combinations of protection and mobility.
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The river darter relies on frictional contact with the substratum to maintain its position while minimizing its energy usage. The river darter's enlarged pectoral fins help create negative lift and increase the friction between its body and the ground to counteract turbidity. As current speed increases, the river darter, like many lotic fishes, increases its frictional contact with the river bottom by releasing gasses from its swim bladder, which increases its density and keeps it near the river bottom.
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Spoonhead sculpins have four soft pelvic rays (soft-rays are thin and flexible), 14-16 pectoral rays, one chin pore and three preopercular spines. They do not have palatine teeth. These fish usually live to be 6 years old compared to slimy sculpins that usually live for 5 years and deepwater sculpins live for 7 years. The spoonhead sculpin does not contain a swim bladder which, allows it to rest on the bottom of lakes and rivers.
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Breeding, as with most other tetras, can be difficult due to the few obvious differences between the genders. However, males are usually slimmer and smaller than females. Also, a visible difference in the shape of the swim bladder can be seen above and behind the silverish abdominal cavity. To breed these fish, they should be given a small, dedicated breeding tank planted with thick bunches of fine-leaved plants such as Myriophyllum on which they can lay eggs.
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This is likely to be related to the interpretation of bio-electrical signals. Secondly, the semicircular canals in the inner ear have an unusual structure and are associated with a gas-filled bladder entirely separate from the main swim bladder. Some species possess modifications of the mouthparts to facilitate feeding upon small invertebrates buried in muddy substrates. The shape and structure of these leads to the popular name of "elephant-nosed fish" for those species with particularly prominent mouth extensions.
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The anal fin has two spines with 15 to 17 soft rays posterior to the spines. Lateral line scales and cheek scales are also distinctive, with sand whiting possessing 60 to 69 lateral line scales and cheek scales positioned in 3-4 rows, all of which are ctenoid. The amount of vertebrae are also diagnostic, having 32 to 34 in total. The swim bladder has rudimentary tubules projecting anteriorly and a series laterally that diminish in size and become sawtooth-like posteriorly.
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The duct like process on the ventral surface of the swim bladder is present. The colour of the fish is a light sandy brown above, with a paler brown to white on the underside and a poorly defined silvery mid-lateral band. The scale margins are occasionally slightly darker than the centres, giving a vague mesh-like appearance above the lateral line. All the fins are transparent, the only exception being the spinous dorsal fin which has a dusting of fine black spots.
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The swim bladder in these fish is reduced, and the skull is mostly cartilaginous and not well-ossified, unlike the adults of most larger ictalurids. The lateral line is fragmentary and never reaches past the anterior part of the anal fin. This species also has a few paedomorphic traits (indicated by small size, kidney morphology, and weak ossification of the skeleton). This species grows to about TL. The widemouth blindcat is a vulnerable species, and is threatened by groundwater pollution.
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There are 84 to 90 lateral line scales and the species has a total of 42 vertebrae. The species is known to grow to a length of 44 cm. Another unique feature of this species is its severe reduction or even absence of a swim bladder, which all other members of the family Sillaginidae possess. The Gangetic whiting also has a small mouth with a much shorter lower jaw than upper jaw, with the two anteriormost teeth larger than the rest.
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The oriental trumpeter whiting, Sillago aeolus, is a widely distributed species of benthic inshore fish in the smelt-whiting family. The species ranges from east Africa to Japan, inhabiting much if the southern Asian and Indonesian coastlines. Its morphology is very similar to other species within the genus Sillago, with a long, compressed body and silvery overall colour. It can be distinguished from its relatives by colour patterns and particularly swim bladder morphology, which helps define most species of Sillago.
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The gill membranes are fused, and the gill opening is either a slit or pore underneath the throat. The swim bladder and ribs are also absent. These are all believed to be adaptations for burrowing into soft mud during periods of drought, and swamp eels are often found in the mud underneath a dried-up pond. Most of the species can breathe air, allowing them to survive in low-oxygenated water, and to migrate overland between ponds on wet nights.
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The family Cetopsidae includes species of small- to medium- sized catfishes which share an anal fin with a long base, the lack of nasal barbels, and, usually, a lack of dorsal and pectoral fin spines. In Cetopsinae, the swim bladder is highly reduced and is enclosed in a bony capsule. Cetopsines lack an adipose fin, while it may be present (though small) in Helogeneinae. Many species are characterized by small eyes obscured by a thick, overlying integument that make them appear blind.
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The impact of gill and skin sphaerosporosis of common carp on carp aquaculture cannot presently be estimated but an increased occurrence of S. molnari proliferative blood stages in carp ponds in Czech Republic and Hungary was reported in 2014. A link to increasing pond temperatures due to climate change was proposed.Holzer AS, Hartigan A, Patra S, Pecková H, Eszterbauer E (2014) Molecular fingerprinting of the myxozoan community in common carp suffering Swim Bladder Inflammation (SBI) identifies multiple etiological agents. Parasites & Vectors 7:398.
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Sillago is a genus of fish in the family Sillaginidae and the only non- monotypic genus in the family. Distinguishing the species can be difficult, with many similar in appearance and colour, forcing the use of swim bladder morphology as a definitive feature. All species are benthic in nature and generally coastal fish, living in shallow, protected waters although there are exceptions. Minor fisheries exist around various species of Sillago, making them of minor importance in most of their range.
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He travelled widely during his time at the Museum, spending time in the United States and on oceanographic expeditions on a number of research vessels. Following advice from Albert Eide Parr he specialised in studying the swim bladder, especially that of deep-sea fish. He also conducted a well received series of lectures at Harvard University and worked at the Woods Hole Oceanographic Institution in 1963. He also worked at the University of Miami and the Scripps Institution of Oceanography.
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Pressure detection uses the organ of Weber, a system consisting of three appendages of vertebrae transferring changes in shape of the gas bladder to the middle ear. It can be used to regulate the buoyancy of the fish. Fish like the weather fish and other loaches are also known to respond to low pressure areas but they lack a swim bladder. Current detection is a detection system of water currents, consisting mostly of vortices, found in the lateral line of fish and aquatic forms of amphibians.
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Like all sillaginids, the rough whiting has an elongate compressed body profile which tapers toward the small terminal mouth. The first spinous dorsal fin has 11 spines and the second dorsal fin has one spine and 17 soft rays. The anal fin has two spines and 17 soft rays. Between the base of first dorsal-fin spine and the lateral line 4 scales, although the amount of lateral line scales is not known, as is the case with vertebrae numbers, colour, and swim bladder morphology.
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It is virtually impossible to define a particular color pattern as belonging to a specific breed; however, in general, wild fish are claimed to have more vivid colors and patterns. Trout have fins entirely without spines, and all of them have a small adipose fin along the back, near the tail. The pelvic fins sit well back on the body, on each side of the anus. The swim bladder is connected to the esophagus, allowing for gulping or rapid expulsion of air, a condition known as physostome.
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The adult has a less pronounced fork in the tail, with body colors of silver, yellow, and reddish brown. The scales are very small, and the two lateral lines have a considerable overlap. Being a Subantarctic species, the black cod has special adaptations such as antifreeze proteins in its blood, as well as adipose tissues to offset its lack of a swim bladder, giving it neutral buoyancy. Sablefish, Anoplopoma fimbria, is occasionally called black cod, as well, but it is not a true cod.
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The swim bladder, anterior vertebrae and the dorsal cranial muscles have been modified to form a drum like sound generator, this is sexually dimorphic with the apparatus being different in each sex. Older juvenile and adult males show a lump on the head caused by hypertrophy of the muscles used to make the drumming sounds they use in courtship. Spawning for the striped cusk eel begins in the summer. Courting and spawning rituals include the creation of sound and close, synchronized movements from a breeding pair.
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Although the sunfish descended from bony ancestors, its skeleton contains largely cartilaginous tissues, which are lighter than bone, allowing it to grow to sizes impractical for other bony fishes. Its teeth are fused into a beak-like structure, which prevents them from being able to fully close their mouths, while also having pharyngeal teeth located in the throat. The sunfish lacks a swim bladder. Some sources indicate the internal organs contain a concentrated neurotoxin, tetrodotoxin, like the organs of other poisonous tetraodontiformes, while others dispute this claim.
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Fish can sense sound through their lateral lines and their otoliths (ears). Some fishes, such as some species of carp and herring, hear through their swim bladders, which function rather like a hearing aid. Hearing is well-developed in carp, which have the Weberian organ, three specialized vertebral processes that transfer vibrations in the swim bladder to the inner ear. Although it is hard to test sharks' hearing, they may have a sharp sense of hearing and can possibly hear prey many miles away.
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There are no anal fins. Like other elasmobranches, sawfish lack a swim bladder (instead controlling their buoyancy with a large oil-rich liver), have a skeleton consisting of cartilage, and the males have claspers, a pair of elongated structures used for mating and positioned on the underside at the pelvic fins. The claspers are small and indistinct in young males. Their small intestines contain an internal partition shaped like a corkscrew, called a spiral valve, which increases the surface area available for food absorption.
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When they emerge from their sheltesr at night they have been found to use vocalisations, popping, to maintain social contactwithin a shoal. They perceive sounds through a specialisation of the swim bladder, Baudelot's ligament and their lateral line. Gravid females have been collected from mid November up until February and spawning has been observed to occur at the same timeo with the juveniles settling from January to April. The juveniles have been recorded from weed growing along rock shorelines in the late (Austral) summer.
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Another threat to the totoaba is from human poaching: the swim bladder is a valuable commodity, as it is considered a delicacy in Chinese cuisine; the meat is also sought-after for making soups. It can fetch high prices - 200 bladders may be sold for $3.6 million at 2013 prices - as it is erroneously believed by many Chinese to be a treatment for fertility, circulatory, and skin problems.Stickney, R. (25 April 2013) "Multi-Million Dollar Fish Bladder Factory Uncovered in Calexico". NBC San Diego.
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The Asian whiting, Sillago asiatica, is a species inshore marine fish in the smelt whiting family, Sillaginidae, distributed along the Asian coastline from the Gulf of Thailand to Taiwan. The Asian whiting's appearance is very similar to other closely related species in the genus Sillago, with swim bladder morphology and ray counts of fins the most reliable identifying features. The species inhabits slightly deeper water than many of the sillaginid species its distribution overlaps, forming an important part of the whiting fishery in the countries within its range.
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The Amiidae are a family of basal ray-finned fishes. The bowfin is the only species to survive today, although additional species in all four subfamilies of Amiidae are known from Jurassic, Cretaceous, and Eocene fossils. Bowfins are now found throughout eastern North America, typically in slow-moving backwaters, canals, and ox-bow lakes. When the oxygen level is low (as often happens in still waters), the bowfin can rise to the surface and gulp air into its swim bladder, which is lined with blood vessels and can serve as a primitive lung.
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This is the basis of the alveolar tissue found in the swim bladder, and is believed to be one of the primary methods by which Megalops "breathes". These fish are obligate air breathers, and if they are not allowed to access the surface, they will die. The exchange of gas occurs at the surface through a rolling motion that is commonly associated with tarpon sightings. This "breathing" is believed to be mediated by visual cues, and the frequency of breathing is inversely correlated to the dissolved content of the water in which they live.
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The study also showed that male E. colini incubated the eggs by fanning/mouthing the clutch until it hatched, and females were sometimes observed to consume the larvae after hatching. E. colini spawn regularly for a period of 12 months, and embryos hatch with a fully functional mouth, inflated swim bladder, pigmented eyes, and two visible otoliths. After hatching, larvae tend to swim up to the surface of the water, as they are attracted to the light and feed on rotifers starting at around 12 hours after hatching.
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Batrachoididae is the only family in the ray-finned fish order Batrachoidiformes. Members of this family are usually called toadfish, or "frogfish": both the English common name and scientific name refer to their toad-like appearance (batrakhos is Greek for frog). Toadfish are benthic ambush predators that favor sandy or muddy substrates where their cryptic coloration helps them avoid detection by their prey. Toadfish are well known for their ability to "sing", males in particular using the swim bladder as a sound-production device used to attract mates.
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Named after their whale-shaped body (from the Greek ketos meaning "whale" or "sea monster", mimos meaning "imitative" and the Latin forma meaning "form"), the Cetomimiformes have extremely large mouths and highly distensible stomachs. Their eyes are very small or vestigial; the lateral line (composed of huge, hollow tubes) is consequently very well developed to compensate for life in the pitch black depths. The dorsal and anal fins are set far back; all fins lack spines. The swim bladder is also absent, except in the larvae and juveniles which occur in the surface waters.
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Macroscopic lesions in affected fish are typical of an acute systemic disease with strong congestion in the internal organs and different levels of hemorrhages in the swim bladder, intestine, liver, peritoneum, spleen and kidney. Also, enlargement of the spleen, focal areas of necrosis in the liver and spleen, pericarditis, hemorrhagic fluid in the intestine, and yellowish exudate covering the brain surface are typically observed. Histopathology is found mainly in the eyes and internal organs’ capsules. Lesions on the ocular area consist of extensive fibroplasias with inflammatory cells penetration.
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An image showing the siphuncle, the tube which connects the current living shell to the previous ones. Removing water from the chambers of the shell reduces the overall density of the shell, and thus the shell behaves as a flotation device comparable to the swim bladder in bony fish. Typically, cephalopods maintain a density close to that of sea water, allowing them to swim with the minimum of effort. In the geologic past, many cephalopods grew to an enormous size (perhaps approaching ten meters in length) thanks to this.
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Hypsidoris is an extinct genus of catfish, classified within its own family Hypsidoridae, from the Eocene epoch of North America. Hypsidoris was about long, and looked similar to the modern catfish, also possessing sensitive barbels used to detect prey in murky waters. It also had a vibration-sensitive organ called the Weberian apparatus, which consisted of specialized vertebrae at the front of the spinal column which passed vibrations to the inner ear, using the swim bladder as a resonance chamber. For defense against predators, Hypsidoris had large spines at the front of each pectoral fin.
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The swim bladder or gas bladder is an internal organ that contributes to the ability of a fish to control its buoyancy, and thus to stay at the current water depth, ascend, or descend without having to waste energy in swimming. The bladder is found only in the bony fishes. In the more primitive groups like some Leuciscinae, bichirs and lungfish, the bladder is open to the esophagus and doubles as a lung. It is often absent in fast swimming fishes such as the tuna and mackerel families.
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Fishes of the superorder Ostariophysi possess a structure called the Weberian apparatus, a modification which allows them to hear better. This ability may explain the marked success of ostariophysian fishes. The apparatus is made up of a set of bones known as Weberian ossicles, a chain of small bones that connect the auditory system to the swim bladder of fishes. The ossicles connect the gas bladder wall with Y-shaped lymph sinus that is next to the lymph-filled transverse canal joining the saccules of the right and left ears.
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Large eyes can better detect light (including bioluminescent light), which is scarce in deep water. The giant squid probably cannot see colour, but it can probably discern small differences in tone, which is important in the low-light conditions of the deep ocean. Giant squid and some other large squid species maintain neutral buoyancy in seawater through an ammonium chloride solution which is found throughout their bodies and is lighter than seawater. This differs from the method of flotation used by most fish, which involves a gas-filled swim bladder.
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The gills of most teleost fish help to eliminate ammonia from the body, and fish live surrounded by water, but most still have a distinct bladder for storing waste fluid. The urinary bladder of teleosts is permeable to water, though this is less true for freshwater dwelling species than saltwater species. Most fish also have an organ called a swim-bladder which is unrelated to the urinary bladder except in its membranous nature. The loaches, pilchards, and herrings are among the few types of fish in which a urinary bladder is poorly developed.
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These fish are known to be quite vocal when captured, emitting loud grunts (Eichelsheim, 2010). Although referred to as “vocalization”, sounds are not actually made through laryngeal mechanics but are thought to be produced by contracting pairs of intrinsic sonic muscles in the swim bladder. The growling sound is a nocturnal vocalization emitted at night and singly, whereas the grunts is produced when the animals are grouped. Grunts sounds last 0.2 seconds and can be heard without any advice, their frequency range are from 250 to 300 Hz (Clara & Amorim, 2006).
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Gars have been referred to as primitive fish or living fossils because they have retained some morphological characteristics of their earliest ancestors, such as a spiral valve intestine, and a highly vascularized swim bladder lung that supplements gill respiration for breathing both air and water. Gars are highly evolved; therefore, referring to them as primitive fish simply means they have existed for a long time, having evolved over millions of years into a more perfected morphological state, not that the animal is primitive in the sense that it is not fully developed.
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The Antarctic toothfish has a lightweight, partially cartilaginous skeleton, lacks a swim bladder, and has fatty deposits which act as a stored energy source, particularly during spawning. This fat also makes large toothfish neutrally buoyant. Many toothfish caught over the seamounts are very depleted of fat, and this is thought perhaps to be related to spawning and spawning migration, which are energy-demanding activities.Fenaughty, J.M.; Eastman, J.T.; and Sidell, B.D. (2008). Biological implications of low condition factor “axe handle” specimens of the Antarctic toothfish, Dissostichus mawsoni, from the Ross Sea.
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Dissection of a bowfin swim bladder Bowfin, like other physostomes such as bichirs (Polypteridae), gars (Lepisosteidae), and the lungfish (Dipnoi), are capable of bimodal respiration. They can extract oxygen from the water when breathing through their gills, and can also break the water's surface to breathe or gulp air through a small pneumatic duct connected from their foregut to the gas bladder. When performing low-level physical activity, bowfin obtain more than half of their oxygen from breathing air. Bowfin have two distinct air- breathing mechanisms used to ventilate the gas bladder.
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Weberian apparatus and air-bladder of a carp The Weberian apparatus is an anatomical structure that connects the swim bladder to the auditory system in fishes belonging to the superorder Ostariophysi. When it is fully developed in adult fish, the elements of the apparatus are sometimes collectively referred to as the Weberian ossicles. The presence of the structure is one of the most important and phylogenetically significant distinguishing characteristics of the Ostariophysi. The structure itself consists of a set of minute bones that originate from the first few vertebrae to develop in an embryonic ostariophysan.
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The juveniles of the butterfly kingfish are characterized by enormous pelvic fins that are longer than the length of its head, and that become more proportional as the fish grows. At any size, the pelvic fin tucks into a deep ventral groove, in much the same way as the first dorsal spines do in all scombrids. This species has very large cycloid scales, below which is a thick layer of fat. The swim bladder has two anterior projections that extend into the back of the skull, near the inner ear.
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The Pacific blue-eye is found in loose schools of tens to thousands of fish. They are generally found in the mid- to upper water column within 1 metre (3 ft) of the riverbank and often close to underwater cover. The Pacific blue-eye is euryhaline—it can survive in a wide range of water salinities from fresh-water to marine environments. It responds to changes in salinity (and resulting change in buoyancy) by changing the volume of its swim bladder, which takes up to 6 hours and 40 minutes when salinity is reduced and around 5 hours when it is increased.
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To understand how presence of a futile cycle helps maintain low levels of ATP and generation heat in some species we look at metabolic pathways dealing with reciprocal regulation of glycolysis and gluconeogenesis. The swim bladder of many fish; such as zebrafish for example - is an organ internally filled with gas that helps contribute to their buoyancy. These gas gland cell are found to be located where the capillaries and nerves are found. Analyses of metabolic enzymes demonstrated that a gluconeogenesis enzyme fructose-1,6- bisphosphatase (Fbp1) and a glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (Gapdh) are highly expressed in gas gland cells.
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The Indian whiting is one of 29 species in the genus Sillago, which is one of three divisions of the smelt whiting family Sillaginidae. The smelt- whitings are Perciformes in the suborder Percoidea. The species was first named by McKay in his comprehensive review of the Sillaginidae, with coauthors Dutt and Sujatha contributing the section on S. indica. The species was previously misidentified as Sillago parvisquamis by the latter two authors in earlier publications, with McKay pointing out the only noticeable difference between the two is the swim bladder morphology, as well as an indistinct black band in the side of the fish.
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It is now clear that the common ancestor of the bony fishes (Osteichthyes) had a primitive air-breathing lung—later evolved into a swim bladder in most actinopterygians (ray-finned fishes). This suggests that crossopterygians evolved in warm shallow waters, using their simple lung when the oxygen level in the water became too low. Fleshy lobe-fins supported on bones rather than ray-stiffened fins seem to have been an ancestral trait of all bony fishes (Osteichthyes). The lobe-finned ancestors of the tetrapods evolved them further, while the ancestors of the ray-finned fishes (Actinopterygii) evolved their fins in a different direction.
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This species can range from grey to brown in colour and can have dark vertical stripes along its side. It has two dorsal fins and thickened skin on the pelvic fins, which is thought to be an adaptation to allow the fish to rest on the ocean substrate, as it lacks a swim bladder to maintain buoyancy. This species is sexually dimorphic, with the males having longer and darker first dorsal fins than females. At sexual maturation, females (48–49 cm) are significantly larger than males (34–40 cm), and spawning females are larger than non- spawning females.
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Several symptoms can indicate sick fish such as cuts on any of the fins, a change in scale or eye coloration, excretions from the nostrils, scales falling off or the fish frequently rising towards the water surface. Many specialty treatments are available in the market to manage specific diseases. Some of the main diseases frequently picked up by common goldfish are: Swim Bladder Disease is developed when the fish has buoyancy problems due to internal gas build up. The problem may be developed when the fish has had less than sufficient amount of fiber, poor water quality, or has been overfed.
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Doradids are easily recognized by a well-developed nuchal shield in front of the dorsal fin, as well as well-developed bony lumps along the lateral line that form thorny scutes. Also, doradids typically have three pairs of barbels (no nasal barbels), an adipose fin, and four to six rays on the dorsal fin with a spine on the anterior (first) ray. These fish are sometimes called "talking catfish" because of their ability to produce sound by moving their pectoral spine or vibrating their swim bladder. Sizes range from SL in Physopyxis lyra to FL and in Oxydoras niger.
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The western trumpeter whiting, Sillago burrus, is a species of marine fish of the smelt whiting family Sillaginidae that is commonly found along the northern coast of Australia and in southern Indonesia and New Guinea. As its name suggests, it is closely related to and resembles the trumpeter whiting which inhabits the east coast of Australia and is distinguishable by swim bladder morphology alone. The species inhabits a variety of sandy, silty and muddy substrates in depths from 0 to 15 m deep, with older fish inhabiting deeper waters. Western trumpeter whiting are benthic carnivores which take predominantly crustaceans and polychaetes as prey.
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The golden lined whiting has a very similar profile to other members of the genus Sillago, with a slightly compressed, elongate body tapering toward the terminal mouth. It differs from some members of the genus in that its ventral profile is more rounded than most other species, which tend to have a flat profile. The number of spines and rays, vertebrae and swim bladder morphology are other distinguishing features. S. analis has a first dorsal fin consisting of 11 spines followed by a second dorsal fin consisting of one spine and between 16 and 18 soft rays.
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The shortnose whiting shares the same basic profile as most of the genus Sillago, possessing an elongate, slightly compressed body tapering toward the terminal mouth. The profile of the species is slightly leaner than most of its close relatives, which may be one initial key to field identification. More definitive diagnostic features include the spine and ray count of the dorsal and anal fins as well as the morphology of the swim bladder. The first dorsal fin consists of 12 or 13 spines, while the second dorsal fin has one spine and 22 to 24 soft rays posterior to the spine.
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The small-eyed whiting is very similar in appearance to other members of the genus Sillago, with the only obvious distinguishing feature of the species being its unusually small eye size (only 14% to 16% of head length), as well as its swim bladder morphology. Other diagnostic features include the spine and ray counts, with the first spinous dorsal fin having 11 spines and the second dorsal fin having one spine and 19 soft rays. The anal fin has two spines followed by 19 soft rays. The species has 34 vertebrae and 68 to 69 lateral line scales, with cycloid cheek scales.
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VHSV is a hemorrhagic disease, meaning it causes bleeding. Internally, the virus can cause petechial hemorrhaging (tiny spots of blood) in internal muscle tissue, and petechial or severe hemorrhaging in internal organs and other tissues. Internal hemorrhaging can be observed as red spots inside a dead fish, particularly around the kidney, spleen, and intestines, as well as the swim bladder, which would normally have a clear membrane. The liver may be pale, mottled with red hyperemic areas, the kidney may be swollen and unusually red, the spleen may be swollen, and the digestive tract may be empty.
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The genera Sillaginodes and Sillaginopsis have the most plesiomorphic characteristics; being monotypic, and distinct from Sillago. Sillago is further divided into three subgenera based primarily on swim bladder morphology; Sillago, Parasillago and Sillaginopodys, which also represent evolutionary relationships. Whilst genetic studies have not been done on the family, they have been used to establish the relationship of what were thought to be various subspecies of school whiting, S. bassensis and S. flindersi.Dixon, P.I., Crozier, R.H., Black, M. & Church, A. (1987): Stock identification and discrimination of commercially important whitings in Australian waters using genetic criteria (FIRTA 83/16).
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The presence and morphology of each species' swim bladder is often their major diagnostic feature, with McKay's three proposed subgenera based on swimbladder morphology alone. The sillaginids have only a small range of body colourings and frequently the only colour characteristics to identify between species are the arrangements of spots and bars on their upper bodies. Most of the family are a pale brown – creamy white colour, while a few species are silver all over. The undersides of the fish are usually lighter than the upper side, and the fins range from yellow to transparent, often marked by bars and spots.
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The swim bladder has a short, blunt anterior median projection with no posterior projection. The southern school whiting has a body colour of creamy brown to rusty above, before an abrupt transition to a silvery white below, with a brilliant longitudinal silver band separating the colours. A narrow rusty brown horizontal band is positioned above the silver band, with irregular red-brown oblique blotches and broken stripes positioned on the back and upper sides, much like Sillago maculata. The dorsal fins have rows of rusty brown or red-orange spots, the anal fins are yellow to hyaline in colour, while all other fins are pale cream, white or hyaline in appearance.
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Lateral view of lungs of a dissected Protopterus dolloi Clod of mud containing the cocoon of lung fish The African lungfish is an example of how the evolutionary transition from breathing water to breathing air can happen. Lungfish are periodically exposed to water with low oxygen content or situations in which their aquatic environment dries up. Their adaptation for dealing with these conditions is an outpocketing of the gut, related to the swim bladder of other fishes, that serves as a lung. The lung contains many thin-walled blood vessels, so blood flowing through those vessels can pick up oxygen from air gulped into the lung.
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Like all smelt-whitings, its body is covered in ctenoid scales, with a lateral line scale count of 66, while the cheek has three rows of scales, those on the upper row cycloid, and on the lower two rows ctenoid. The vertebrae count and swim bladder morphology for the species is currently unknown, but may be revealed by further collecting. The silver-banded whiting's name is derived from the brilliant silvery longitudinal band which runs from the base of the pectoral fin to the base of the caudal fin. The body is an overall dull silvery white, while the breast and operculum are also a silvery colour.
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Being constant swimmers required large amounts of oxygen which is achieved by water passing over their gills, which are in place of lungs to still have a large surface area through the various grooves in the gill tissue. The oxygen is obtained when they exhale and the water is pushed through their pharynx. Their blood flows in the opposite direction (countercurrent exchange) of the water over the gills in able to remove the maximum amount of oxygen from the water. They use a swim bladder to adjust their buoyancy by changing the volume of gas in the bladder to keep an overall constant volume for the bladder at different depths.
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As with most of the genus Sillago, the eastern school whiting has a slightly compressed, elongate body tapering toward the terminal mouth, with the body covered in small ctenoid scales extending to the cheek and head. The most reliable features for distinguishing the species are the number of fins spines and rays and the shape of the swim bladder. The first dorsal fin has 11 spines and the second dorsal fin has 1 leading spine with 16 to 18 soft rays posterior. The anal fin is similar to the second dorsal fin, but has 2 spines with 18 to 20 soft rays posterior to the spines.
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E. lineatus has a total of 10-15 spines in its dorsal fins with the anterior spines of the first dorsal fin being much taller than the middle spines which gives this fin a concave outline. The anal fin has 11 - 12 soft rays and it has a vertebra count of 37. Its body is almost entirely scaleless except for the lateral line and a "corselet" and there is no swim bladder. It is generally iridescent blue in colour with black markings on its back made up of 3 to 5 horizontal stripes, as well as a variable amount of black or dark grey spots above the pelvic fins.
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In a structure similar to plywood, the fibres in each successive layer are oriented at large angles to those in the previous layer, increasing toughness. The hard, corrugated surface of the outer layer, and the tough internal collagen layers work synergistically to contribute to their ability to flex and deform while providing strength and protection—a solution that allows the fish to remain mobile while heavily armored. The arapaima has a fundamental dependence on surface air to breathe. In addition to gills, it has a modified and enlarged swim bladder, composed of lung-like tissue, which enables it to extract oxygen from the air.
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The swim bladder is reduced in size in this fish and it spends much of its time hopping around and perching on the riverbed, propped up by its pelvic fins, in the manner of a goby. During feeding, it repeatedly dives head first into the sediment with its mouth open wide, and then expels sand through its gill chambers. In readiness for breeding, a pair of R. lapidifer forms a nest about across in a gravelly area of the river bed. Adult fish have been observed carrying small pebbles in their mouths to build the nest, hence the specific name lapidifer (bearer of stones).
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Pterois miles hunting glassfish According to a study that involved the dissection of over 1,400 lionfish stomachs from Bahamian to North Carolinian waters, Pterois fish prey mostly on small fish, invertebrates, and mollusks in large amounts, with some specimens' stomachs containing up to six different species of prey. The amount of prey in lionfish stomachs over the course of a day suggests lionfish feed most actively from 7:00–11:00 a.m., and decrease feeding throughout the afternoon. Lionfish are skilled hunters, using specialized bilateral swim bladder muscles to provide precise control of location in the water column, allowing the fish to alter its center of gravity to better attack prey.
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All species of catfishes can generate sound through stridulation, and many produce sounds through drumming. Stridulation consists of the clicking or grinding of bony parts on the fish's pectoral fins and pectoral girdle, and drumming consists of the contraction of specialized sonic muscles with subsequent reverberation through the swim bladder. Variability in the sound signals created by the channel catfish depends on the mechanism by which the sound is produced, the function of the resultant sound, and physical factors such as sex, age, and temperature. This variation may result in increased complexity of the outgoing signal and may allow for increased usefulness of the signal in interspecies communication.
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As their vascularised swim bladders can function as lungs, most gars surface periodically to take a gulp of air, doing so more frequently in stagnant or warm water when the concentration of oxygen in the water is low. Experiments on the swim bladder has shown that the temperature of the water affects which respiration method the gar will use: aerial or aquatic. They will increase the aerial breathing rate (breathing air) as temperature of the water is increased. Gars can live completely submerged in oxygenated water without access to air and remain healthy while also being able to survive in deoxygenated water if allowed access to air.
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As the fish came close to breeding, they began to spend a greater amount of time in the pelagic zone. With the lack of a swim bladder, the fish were able to make rapid movements through the water column, moving between surface waters and depths of over within one day. Data from research surveys and data-storage tags show that adult lumpfish alter their behaviour between night and day with the fish spending more time in the pelagic zone at night and found associated with the seabed during the day, the reasons for this are unclear. This fish is now considered to be a semi-pelagic/semi-demersal fish.
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Possibly the most obvious identifying feature of the species is the characteristic pelvic fin, of which the first ray is modified into a laterally compressed club-like structure that overlaps the much reduced ventral spine at the base of the fin. Other distinguishing features include 66 to 73 lateral line scales and a total of 35 vertebrae. The swim bladder morphology is also very distinct in the Club-foot whiting, with a structure very different from the rest of the Sillaginidae. It is a very flat, non functional structure that sits just behind the axis vertebra and abruptly narrows to a fine point terminating at the 9th abdominal vertebrae.
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Another example suggest that heat generation in fugu swim bladder will be transported out of the site of generation, however it may still be constantly recovered back through the rete mirabile so as to maintain the temperature of the gas gland higher than other areas of the body. _The overall net reaction of the futile cycle involves the consumption of ATP and generation of heat as follows:_ ATP + H2O --> ADP + Pi + Heat Another example of futile cycle benefiting in generation of heat is found in bumble bees. The futile cycle involving Fbp and Pfk is used by bumble bees to produce heat in flight muscles and warm up their bodies considerably at low ambient temperatures.
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It is differentiated from its congeners in a number of ways, the first being the absence of a swim bladder. Its palatine bone is also wider than other members of its genus and its otolith is oval-shaped where its congeners' are rectangular. In the eastern Atlantic Ocean there are three stocks differentiated by location and time at which spawning occurs, but studies have not found any distinct genetic differences between these populations. Genetic differences only start to appear at the transatlantic scale, a fact supported by a lack of migration between western and eastern Atlantic populations, whereas eastern Atlantic stocks are known to converge in certain locations like the Norwegian Sea and North Sea.
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Many hypoxic environments never reach the level of anoxia and most fish are able to cope with this stress using different physiological and behavioural strategies. Fish that use air breathing organs (ABO) tend to live in environments with highly variable oxygen content and rely on aerial respiration during times when there is not enough oxygen to support water-breathing. Though all teleosts have some form of swim bladder, many of them are not capable of breathing air, and they rely on aquatic surface respiration as a supply of more oxygenated water at the surface of the water. However, many species of teleost fish are obligate water breathers and do not display either of these surface respiratory behaviours.
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Gills The major means of respiration in teleosts, as in most other fish, is the transfer of gases over the surface of the gills as water is drawn in through the mouth and pumped out through the gills. Apart from the swim bladder, which contains a small amount of air, the body does not have oxygen reserves, and respiration needs to be continuous over the fish's life. Some teleosts exploit habitats where the oxygen availability is low, such as stagnant water or wet mud; they have developed accessory tissues and organs to support gas exchange in these habitats. Several genera of teleosts have independently developed air- breathing capabilities, and some have become amphibious.
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The golden lined whiting, Sillago analis (also known as the Tin Can Bay whiting or rough-scale whiting), is a species of inshore marine fish of the smelt whiting family, Sillaginidae that inhabits the coastlines of northern Australia and lower Papua New Guinea. The golden lined whiting can be more readily distinguished by its colour than other whitings in the genus Sillago, although swim bladder morphology and spine and ray counts are the most precise method of identification. S. analis is an opportunistic predator, taking a variety of crustaceans, polychaetes and molluscs, with a transition of diet seen as the fish mature. One unusual aspect about the species diet is the large amounts of molluscan siphons it takes.
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The distinction between demersal species of fish and pelagic species is not always clear cut. The Atlantic cod (Gadus morhua) is a typical demersal fish, but can also be found in the open water column, and the Atlantic herring (Clupea harengus) is predominantly a pelagic species but forms large aggregations near the seabed when it spawns on banks of gravel. Two types of fish inhabit the demersal zone: those that are heavier than water and rest on the seabed, and those that have neutral buoyancy and remain just above the substrate. In many species of fish, neutral buoyancy is maintained by a gas-filled swim bladder which can be expanded or contracted as the circumstances require.
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The generalized structure of the Weberian apparatus is akin to a skeletal complex of bones and ossicles that are physically connected to the labyrinth auditory complex anteriorly and the anteriormost region of the swim bladder posteriorly. The entire structure is derived from skeletal elements of the first four vertebrae. The involved elements include: the supraneural bones of the skull; modified neural arch bones, specifically the paired claustra and the scaphia; the intercalarium and the lateral processes; the tripus; the os suspensorium from the fourth vertebra; the parapophysis of vertebra number five including the vertebra itself, plus the vertebra's corresponding pleural rib. In addition, a structure composed of fused neural spines form the dorsalmost part of the Weberian apparatus.
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The vesica piscis is the intersection of two congruent disks, each centered on the perimeter of the other. The vesica piscis is a type of lens, a mathematical shape formed by the intersection of two disks with the same radius, intersecting in such a way that the center of each disk lies on the perimeter of the other.. In Latin, "vesica piscis" literally means "bladder of a fish", reflecting the shape's resemblance to the conjoined dual air bladders ("swim bladder") found in most fish. In Italian, the shape's name is mandorla ("almond"). Euclid's Elements This figure appears in the first proposition of Euclid's Elements, where it forms the first step in constructing an equilateral triangle using a compass and straightedge.
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The anatomy of Lampanyctodes hectoris (1) operculum (gill cover), (2) lateral line, (3) dorsal fin, (4) fat fin, (5) caudal peduncle, (6) caudal fin, (7) anal fin, (8) photophores, (9) pelvic fins (paired), (10) pectoral fins (paired) Swim bladder of a rudd (alt=Photo of white bladder that consists of a rectangular section and a banana-shaped section connected by a much thinner element Most fish move by alternately contracting paired sets of muscles on either side of the backbone. These contractions form S-shaped curves that move down the body. As each curve reaches the back fin, backward force is applied to the water, and in conjunction with the fins, moves the fish forward. The fish's fins function like an airplane's flaps.
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The body of glass squids (Cranchiidae) is mainly filled by a transparent coelom containing ammonium ions for buoyancy. Unlike nautiloids which have gas-filled chambers inside their shells which provide buoyancy, and octopuses which live near and rest on the seabed and do not require to be buoyant, many squid have a fluid-filled receptacle, equivalent to the swim bladder of a fish, in the coelom or connective tissue. This reservoir acts as a chemical buoyancy chamber, with the heavy metallic cations typical of seawater replaced by low molecular- weight ammonium ions, a product of excretion. The small difference in density provides a small contribution to buoyancy per unit volume, so the mechanism requires a large buoyancy chamber to be effective.
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Some, such as Nautilus, allow gas to diffuse into the gap between the mantle and the shell; others allow purer water to ooze from their kidneys, forcing out denser salt water from the body cavity; others, like some fish, accumulate oils in the liver; and some octopuses have a gelatinous body with lighter chlorine ions replacing sulfate in the body chemistry. The Macrotritopus defilippi, or the sand- dwelling octopus, was seen mimicking both the coloration and the swimming movements of the sand-dwelling flounder Bothus lunatus to avoid predators. The octopuses were able to flatten their bodies and put their arms back to appear the same as the flounders as well as move with the same speed and movements. Females of two species, Ocythoe tuberculata and Haliphron atlanticus, have evolved a true swim bladder.
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The aquaculture potential for sand whiting was first investigated in the late 1980s, with a number of reports detailing both successful trials and also a number of problems with such trials. A 1988 study showed that sand whiting were more likely to grow in captivity than other whiting species, but the mortality rate of over 50% was unacceptable for use in an economic setting. A number of problems with diseases such as ulcerative dermatitis and the failure of the swim-bladder to inflate properly were also documented, however many of these initial problems have been overcome, and some facilities are breeding around 2000 larvae with a 95% survival rate. Some of these fingerlings are used to restock depleted estuaries, while others form the basis of commercial fish crops.
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However, they often lack a basilar papilla, having instead an entirely separate set of sensory cells at the upper edge of the saccule, referred to as the papilla amphibiorum, which appear to have the same function. Although many fish are capable of hearing, the lagena is, at best, a short diverticulum of the saccule, and appears to have no role in sensation of sound. Various clusters of hair cells within the inner ear may instead be responsible; for example, bony fish contain a sensory cluster called the macula neglecta in the utricle that may have this function. Although fish have neither an outer nor a middle ear, sound may still be transmitted to the inner ear through the bones of the skull, or by the swim bladder, parts of which often lie close by in the body.
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The chub mackerel has a well-developed swim bladder attached with the esophagus, which the "true mackerels" in the genus Scomber lack, and a characteristic color difference is seen between the chub and the Atlantic chub, the latter being silvery-sided below the midline, whereas the lower part of the sides of the chub (otherwise colored somewhat like the Atlantic) are mottled with small dusky blotches, and the chub has a larger eye than the Atlantic. Less obvious differences are that the dorsal fins are closer together in the chub and only 9 or 10 spines are in its first dorsal fin instead of 11 or more, which is the usual count in the Atlantic mackerel. In most species, the mackerel is known to travel in large schools. It is a smaller fish than its better-known relatives, growing to a length around .
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702 pp This is a deep-water species and its swim bladder is badly damaged by being brought up to the surface from the depths; the advice for sport anglers is, therefore, that boat-caught ling should not be returned to the sea and that they should stop fishing when enough have been caught for the table. The stock is thought to be reasonably good, but the IUCN has stated that no data are available on the population size or any population trends, that the population in the Mediterranean Sea may be marginal, with the major portion of its global range in the Atlantic. So, no data are available to allow a determination the status of the ling beyond data deficient. Ling is regarded as a "fish to avoid" for consumers by the Marine Conservation Society because it is trawled.
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