Brevoortia tyrannus can be described as a silvery in color. However, the sides of it differ from the silver color and range closer to a brassy color. Menhadens have dark bluish green backs. They are usually characterized by a small, irregularly placed scales on their backs, above their anal fins. They are also characterized by a black spot that is usually behind their gill openings. Following this larger black spot are approximately six lines of smaller spots. They have inner and outer finrays and a pelvic fin with rounded hind margins.
Average mass: 1283 g.
Other Physical Features: bilateral symmetry
For the most part menhadens can be found at a depth of up to -20m. This puts them in the palagic, brakish, marine area of the Atlantic Ocean. In this habitat predators of the menhadens consist of such aquatic animals as sharks, rays, and bony fish. Also, parasites like isopods, copepods, cestodes, and trematodes are found on the menhadens.
Aquatic Biomes: coastal
Brevoortia tyrannus, commonly called the Atlantic Menhaden, can be found anywhere in the western Atlantic, Nova Scotia, Canada and southward to Indian River, Florida, USA. Menhaden are also common in all salinities of the Chesapeake Bay.
Biogeographic Regions: atlantic ocean (Native )
Menhadens feed by filtering. They consume from the primary trophic levels, including phytoplankton and zooplankton. Their main food source also includes detritus(dead organic matter found in the water, usually settled on the bottom), plants/detritus and animals. Menhadens' food consumption is usually 31.40 times their body weight per year.
Menhadens are considered highly commercial fish for the United States. They are used in the production of such things as: oil, fertilizer and fishmeal. They can also be found marketed for consumption, either fresh, smoked, salted, or canned. This species was realized recently to have a very significant value as an alternative for whale oil. They are also used for lubricants and as fuel for lamps. Since these fish have begun to be used as an alternative oil, they are being used for making soaps and paints. Virginia, North Carolina and the Gulf are major ports for the menhaden. There are more menhaden brought onto US land each year than any other fish. Their input ranges from 300,000 to 400,000 metric tons per year.
Menhadens by themselves are considered a harmless species. However, when large numbers of these fish come in contact with the dinoflagellate Pfiesteria piscicida, many health risks become readily exposed to humans. Pfiesteria changes into a toxic encysted stage when it inhibits the menhadens. This causes health risks ranging from epidermal problems to central nervous system problems.
Menhaden are not threatened in or around the United States. They do not appear in the IUCN red list, which means that their species is safe from extinction as of now. Examples of regulations and status of menhaden can be found at NOAA (1999).
US Federal List: no special status
CITES: no special status
Perception Channels: tactile ; chemical
Spawning for menhadens occurs all year long. However, productive spawning has been noted to occur from March to May and again between September and October. Estuaries are usually the safest salt water havens within menhadens habitat so their nurseries occur there. Breeding can be limited by high water temperatures.
El menhaden de l'Atlàntic[4] (Brevoortia tyrannus) és una espècie de peix pertanyent a la família dels clupèids.[5]
Té lloc durant tot l'any i les larves són pelàgiques.[8][9][10][11][12][13][14][15][16][17][18]
Menja fitoplàncton (diatomees), zooplàncton (crustacis petits i anèl·lids) i detritus.[19][20]
És parasitat per isòpodes, copèpodes, cestodes i trematodes.[21]
Als Estats Units és depredat pel llobarro atlàntic ratllat (Morone saxatilis), el corball reial (Cynoscion regalis), la tonyina d'aleta blava (Thunnus thynnus),[22] el peix espasa (Xiphias gladius), el tallahams (Pomatomus saltator),[23] el tauró sedós (Carcharhinus falciformis), el solraig (Isurus oxyrinchus),[24] l'agullat (Squalus acanthias) i el tauró gris (Carcharhinus plumbeus).[25][26]
És un peix marí i d'aigua salabrosa, pelàgic-nerític, oceanòdrom[27] i de clima subtropical (46°N-30°N, 81°W-64°W) que viu entre 0-50 m de fondària.[6][28]
Es troba a l'Atlàntic occidental: des de Nova Escòcia (el Canadà) fins a Indian River (Florida, els Estats Units).[6][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45]
Es comercialitza fresc, en salaó, en conserva o fumat. També és emprat per a produir oli, fertilitzants i farina de peix.[46][47]
No apareix a la Llista Vermella de la UICN, la qual cosa vol dir que es troba fora de perill d'extinció.[8]
És inofensiu per als humans.[6]
El menhaden de l'Atlàntic (Brevoortia tyrannus) és una espècie de peix pertanyent a la família dels clupèids.
Der Atlantische Menhaden oder Bunker (Brevoortia tyrannus) ist ein Fisch aus der Familie der Heringe, der an der nordamerikanischen Atlantikküste von Neuschottland bis Florida, sowie den dortigen Ästuargewässern vorkommt.[1] Nah verwandte Arten treten bis zu argentinischen Küste auf.
Der kleine Heringsartige ist als Filtrierer und Beutetier für Fische und Greifvögel von großer ökologischer Bedeutung. Nachdem er stark befischt wurde und seine Bestände dadurch einbrachen, wurden ab 2013 Fangquoten eingeführt, um einer Überfischung entgegenzuwirken.
Der Körper ist seitlich abgeflacht mit scharf gekieltem Bauch. Der große, schuppenlose Kopf macht fast ein Drittel der Gesamtkörperlänge von bis zu 50 cm aus. Der Rücken ist dunkel blaugrün, Seiten, Bauch und Flossen sind silbrig mit bronzenem Glanz. Hinter dem Kiemendeckel sitzt ein deutlicher schwarzer Fleck, eine Reihe kleinerer Flecken folgt entlang der Flanke. Bauch- und Afterflosse haben jeweils 18 bis 24 Weichstrahlen, die Schwanzflosse ist deutlich gekerbt.
Die Schwarmfische ernähren sich als Filtrierer, indem sie das Wasser vornehmlich nach Phyto-, aber auch nach Zooplankton durchsieben.[2]
Vom Frühling bis zum Spätherbst finden sich die kleinen Fische in der Nähe der Küsten, sowie in Flussmündungen zu großen Schwärmen zusammen. Im Herbst und frühen Winter entfernen sich geschlechtsreife Fische 30 bis 50 Kilometer von der Küste, um im offenen Wasser zu laichen. Nach zwei bis drei Tagen schlüpfen die Fischlarven, die von der Strömung in Küstennähe getrieben werden, wo sie ihr erstes Lebensjahr verbringen. Im Alter von einem bis drei Jahren ist der Menhaden, der eine Lebenserwartung von bis zu zehn Jahren hat, geschlechtsreif.[1]
Die winterlichen Temperaturen haben Einfluss auf die Anzahl an Jungfischen, die im Frühling heranwachsen. Strengere Winter hemmten außerdem das Wachstum der Fischlarven, die in kalten Jahren weniger Nahrung fanden als in wärmeren Wintern.[3]
In vielen Regionen entlang der Atlantikküste war die Anzahl der Jungfische seit den 1990er Jahren stark gesunken.[4] Durch die Einführung von Fangquoten konnte dieser Trend mittlerweile aufgehalten werden und die Bestände sind (2021) dabei sich zu erholen.[5]
Studien konnten mittlerweile nachweisen, dass die Wasserqualität in Gebieten wie der Chesapeake Bay, von der Anwesenheit der kleinen Fische profitieren. Sie spielen eine wichtige Rolle für das Ökosystem, da sie durch ihre Ernährung, außergewöhnlich stark auftretende Algenblüte auf natürliche Weise eindämmen, wodurch sie Gewässer vor dem Umkippen bewahren. Insbesondere Stickstoffeinträge, die durch die Landwirtschaft die Gewässer belasten, werden durch einen stabilen Bestand der kleinen Fische nachweislich reduziert.[6]
Der kleine Heringsartige ist als Teil der Nahrungskette ein wichtiges Beutetier und wird unter anderem von Walen, Delfinen, Wolfsbarschen, Blaufischen sowie dem Fischadler gejagt.[1][6]
Der Menhaden ist an der nordamerikanischen Atlantikküste, unter anderem in der Chesapeake Bay, außerdem für die Fischerei der wichtigstes Fisch. Da er reich an Omega-3-Fettsäuren ist, wird er unter anderem zu Fischöl sowie Nahrungsergänzungsmitteln verarbeitet, aber auch zu Tiernahrung.[4][5]
Die Art gilt offiziell noch nicht als bedroht. Dennoch wurden, in den USA (von der Atlantic States Marine Fisheries Commission), bereits im Dezember 2012 wurden erste Fangbegrenzungen beschlossen, um einer Überfischen entgegenzuwirken.[7]
Im Jahr 2017 warben unterschiedliche Organisationen für die Beibehaltung der Fangquote. Ein stabiler Bestand des Menhaden sei wichtig für eine nachhaltige Erholung der Bestände von Tieren, die auf ihn als Beute angewiesen sind. Außerdem hätten die ursprünglichen Bestände, die vor der umfangreichen Befischung im Meer vorhanden waren, ihr ursprüngliches Niveau noch immer nicht wieder erreicht.[8]
Durch eine noch stärkere Regulierung der Fangquoten, konnte 2021 beobachtet werden, dass nicht nur mehr Wale und Delfine, sondern auch Seehunde, Blauflossen-Thunfische, Haie, Hummer und Weißkopfseeadler von dem reicheren Nahrungsangebot profitierten.[5]
Der Atlantische Menhaden oder Bunker (Brevoortia tyrannus) ist ein Fisch aus der Familie der Heringe, der an der nordamerikanischen Atlantikküste von Neuschottland bis Florida, sowie den dortigen Ästuargewässern vorkommt. Nah verwandte Arten treten bis zu argentinischen Küste auf.
Der kleine Heringsartige ist als Filtrierer und Beutetier für Fische und Greifvögel von großer ökologischer Bedeutung. Nachdem er stark befischt wurde und seine Bestände dadurch einbrachen, wurden ab 2013 Fangquoten eingeführt, um einer Überfischung entgegenzuwirken.
The Atlantic menhaden (Brevoortia tyrannus) is a North American species of fish in the herring family, Clupeidae.[3]
Atlantic menhaden are found in North Atlantic coastal and estuarine waters from Nova Scotia south to northern Florida. They are commonly found in all salinities of the Chesapeake Bay and Mid-Atlantic water. They swim in large schools that stratify by size and age along the coast. Younger and smaller fish are found in the Chesapeake Bay and southern coastline while older, larger fish are found along the northern coastline.[4]
Atlantic menhaden are silvery coloured fishes characterized by a moderately compressed body and a black spot on their shoulder behind their gill openings. They can reach a size of approximately 15 inches.[4]
The Atlantic menhaden is a filter feeder, which that it collects food by filtering water through modifications of the branchial apparatus (gill arches and gill rakers). Its diet depends on the size of their gill rakers, which change as menhaden age. When the rakers are smaller, which generally correspond to when they are under the age of 1, Atlantic menhaden feed primarily on phytoplankton. As they age and their gill rakers grow larger, menhaden shift their diet to primarily consume zooplankton.[5]
Atlantic menhaden can spawn year round in inshore waters off the Atlantic coast, with the highest spawning rates near North Carolina in the late fall. The eggs hatch in the open ocean and the larvae drift to sheltered estuaries via ocean currents. The young spend a year developing in these estuaries before returning to the open ocean. At this early stage, they are commonly known as "peanut bunker". Atlantic menhaden usually do not become sexually mature until the end of their second year, after which they reproduce until death. A young, sexually mature female can produce roughly 38,000 eggs, while a fully mature female can produce upwards of 362,000.[6]
Eggs are buoyant and hatch within 2 to 3 days depending on the temperature. The larvae will spend 1 to 3 months in waters over the continental shelf. The Chesapeake Bay is a popular nursery for juvenile menhaden. Larval fish will enter the Bay in late winter and early summer. The larval fish will move into lower salinity waters in estuarine tributaries while juvenile and immature fish remain in the Bay until the fall. Atlantic menhaden can live up to 10 to 12 years.[4]
Atlantic menhaden are preyed upon by fish such as striped bass, weakfish and bluefish, and by birds such as ospreys and eagles.[7] Humpback whales off the coast of New Jersey feed on Atlantic menhaden.[8][9] Other cetaceans, such as fin whales and dolphins also eat menhaden.[10][11][12][13][14] Dolphins can eat up to 20 pounds of Atlantic menhaden a day.[15]
Menhaden have historically been used as a fertilizer for crops. It is likely that menhaden is the fish that Squanto taught the Pilgrims to bury alongside freshly planted seeds as fertilizer. Other uses for menhaden include: feed for animals, bait for fish, oil for human consumption, oil for manufacturing purposes and oil as a fuel source.
In the early years of the United States, Atlantic menhaden were being harvested by thousands of fishing ships. The Atlantic coastline was lined with processing facilities to quickly transform the fish into a product of worth, typically oil but later fish meal became more popular. Tragedy of the commons set in and the menhaden population began to dwindle. Many of these small companies could not manage, which left only a handful of menhaden fishing companies to remain on the Atlantic coast.[16]
While many sources today claim that the menhaden is inedible, the fish were once consumed as sardines might be, or fried. Maine fishermen, for example, would eat fried pogies for breakfast. The fish that were not sold for bait would be sold to the poorer classes for food.
In the Atlantic, menhaden are targeted by two types of fisheries, a reduction fishery and a bait fishery. They are also taken directly by recreational fishing for use as bait.[17]
The reduction fishery processes whole menhaden into fish meal, fish oil, and fish solubles while the bait fishery supplies fishermen with menhaden as bait for key commercial and recreational fisheries. Both menhaden fisheries use a process known as purse seine fishing, in which two fishing boats surround a single school of fish with a large net. Purse seining is one of the most efficient methods of fishing available, with one of the lowest levels of bycatch.[18] The UN Food and Agriculture Organization has cited the Atlantic and Gulf menhaden fisheries as having one of the lowest levels of bycatch in the world.[19] The reduction fishery is largely based in the Chesapeake Bay and nearby Atlantic waters, and its season runs annually starting in May through the fall.
The bait fishery operates throughout the Atlantic coastline, ranging from North Carolina to New England.[20] Cast nets are also used for bait catch in the recreational fishing sector.
The fishery's sustainability has also been certified by independent organizations. Friend of the Sea, an international seafood sustainability certification program, has recognized both the Atlantic menhaden and Gulf menhaden fisheries as sustainable.[21] This is both due to the healthy status of the stock as well as the fishery's low levels of bycatch, which it achieves with the use of purse seine nets.[22]
Atlantic menhaden are managed by the Atlantic States Marine Fisheries Commission (ASMFC), an interstate compact formed under an agreement by the 15 Atlantic coast states. Like with other species, the ASMFC manages menhaden to prevent overfishing and to keep the stock from being overfished. There is a subtle but distinct difference between the two designations. Overfishing occurs when too many fish are being taken from the population of a fish stock. A stock is considered overfished when it is not able to produce enough new fish to maintain the population.
The ASMFC uses two biological measurements, or reference points, to measure the health of the menhaden stock. To determine if the stock is overfished, the ASMFC measures fecundity (FEC), the number of mature eggs in the menhaden population, which indicates the stock's reproductive capability. To measure overfishing, the ASMFC monitors fish mortality (F), the measure of the amount of fish removed from the water. In 2010, the ASMFC's stock assessment found that the stock's mortality levels were high enough that overfishing was occurring, but its fecundity level indicated that it was not overfished.[23]
Because the ASMFC's 2010 assessment concluded that Atlantic menhaden was experiencing overfishing, some conservation, fishing and other organizations began urging the commission to impose new harvest restrictions, and the ASMFC began the process of drafting new catch limits.[24] This culminated the development of Amendment 2 to the menhaden Fishery Management Plan that established a total allowable catch (TAC) of 170,800 metric tons (376,549,544 pounds), effectively reducing the coastwide harvest by 20 percent compared to average landings from 2009 to 2011.[25]
The cuts followed a sustained campaign by environmental groups like Chesapeake Bay Foundation, as well as authors like Paul Greenberg, who called for a ban on fishing menhaden in US federal waters and the Chesapeake Bay. The decision was opposed by many working in the menhaden fishery, who considered the cuts unnecessary and economically harmful.
The TAC created the first ever coastwide catch limit, though the ASMFC had earlier instituted a harvest cap on the number of menhaden that can be caught in the Chesapeake Bay to address concerns of localized depletion.[26] According to recent reports, the stocks are not overfished in the Chesapeake Bay.[27]
Critics have since evaluated several claims made about the status of menhaden during the development of the 2012 management measures. For example, claims about historic overfishing of menhaden made by the Pew Charitable Trusts were rated “mostly false” by the Providence Journal's Politifact column, which took issue with Pew saying 90 percent decline in abundance had occurred in recent years, rather than citing the 88 percent decline from 1982 to 2008.[28]
The latest stock assessment, published in early 2015, indicates that the stock is not currently subject to overfishing and has not been at an overfished population level since the 1990s.[29] The ASMFC unanimously accepted the stock assessment to use for management in May 2015 and increased the TAC to 187,880 metric tons (414,204,498 pounds). They also voted to begin Amendment 3 to consider changes to the current state‐by‐state allocation scheme and establish ecological reference points to help them, as Menhaden Management Board Chair Robert Boyles stated in the ASFMC's May 6, 2015 press release, fully evaluat[e] the ecological role of Atlantic menhaden through the amendment process.”[30]
While popularly cited as filter feeders that remove excess algae and nutrients from the water, evidence suggests that menhaden do not significantly impact water quality. Adult menhaden largely do not eat phytoplankton, whose excessive growth leads to dead zones, instead feeding mainly on zooplankton.[31] There is evidence that, because menhaden secrete nitrogen, that they may actually be a net contributor to phytoplankton growth.[32]
Separate, but related, to the issue of dead zones are fish kills, where large numbers of menhaden or other fish will turn up dead in a single area. According to the Virginia Institute of Marine Sciences, which investigates fish kills in the Chesapeake Bay, the causes of fish kills are varied, but often are related to environmental factors such as low amounts of oxygen in the water, algal blooms, and water temperatures that are either too hot or too cold. Other factors, such as the dumping hazardous materials or excess bycatch, can also contribute.[33]
Due to the change in striped bass population many have begun to cite the commercial harvesting of menhaden as the reasoning behind the shift. Several claims state that menhaden are a key staple in the striped bass diet. However, other studies see the striped bass as an opportunistic feeder with a variety of aquatic creatures that it consumes and therefore does not completely rely on the menhaden. In fact, menhaden has been represented as low as 8% of the striped bass diet.[34]
The Atlantic menhaden (Brevoortia tyrannus) is a North American species of fish in the herring family, Clupeidae.
Atlantic menhaden are found in North Atlantic coastal and estuarine waters from Nova Scotia south to northern Florida. They are commonly found in all salinities of the Chesapeake Bay and Mid-Atlantic water. They swim in large schools that stratify by size and age along the coast. Younger and smaller fish are found in the Chesapeake Bay and southern coastline while older, larger fish are found along the northern coastline.
Brevoortia tyrannus (sábalo atlántico) es un pez plateado de la familia de los arenques, Clupeidea.[1][2] Vive cerca de las costas norteamericanas del Atlántico Norte, desde Nueva Escocia hasta Florida. Se alimenta de plancton y es un pez filtrador, por lo que juega un papel importante en la clarificación del agua del mar.[3]
Se mueven en grandes grupos y son presas de muchos otros peces y también aves. Aunque prácticamente no se utiliza en alimentación humana, se utiliza mucho para la producción de aceite y harina de pescado.
Datos: Q756893
Multimedia:
Especies: Brevoortia tyrannus
Brevoortia tyrannus (sábalo atlántico) es un pez plateado de la familia de los arenques, Clupeidea. Vive cerca de las costas norteamericanas del Atlántico Norte, desde Nueva Escocia hasta Florida. Se alimenta de plancton y es un pez filtrador, por lo que juega un papel importante en la clarificación del agua del mar.
Se mueven en grandes grupos y son presas de muchos otros peces y también aves. Aunque prácticamente no se utiliza en alimentación humana, se utiliza mucho para la producción de aceite y harina de pescado.
Brevoortia tyrannus Brevoortia generoko animalia da. Arrainen barruko Clupeidae familian sailkatzen da.
Brevoortia tyrannus Brevoortia generoko animalia da. Arrainen barruko Clupeidae familian sailkatzen da.
Menhaden (Brevoortia tyrannus) on pohjoisamerikkalainen sillien heimon kalalaji. Sen arvo ihmisravintona ei kuitenkaan ole yhtä suuri kuin sillin, koska sen liha on varsin öljyistä, mutta se on tärkeä osa valaiden, merilintujen ja haiden ruokavaliota. Sitä käytetäänkin yleensä syöttinä kalastuksessa. Lisäksi siitä tehdään kalajauhoa, kalaöljyä ja lannoitetta.
Menhaden on silliä korkeaselkäisempi, ja sen suomut ovat kampamaisia. Kyljissä on tummia täpliä. Se on noin 30 cm pitkä.
Menhaden ei ole nirso ravintonsa suhteen vaan syö kaiken sopivankokoisen planktonin. Sen suu on suuri, joten se pystyy tehokkaasti hyödyntämään tämän ravinnonlähteen. Se siivilöi ravintoa myös merenpohjan lietteestä.[2]
Menhaden elää Atlantissa Pohjois-Amerikan rannikon tuntumassa Kanadan Nova Scotiasta aina Floridan Indian-joen suulle. Se liikkuu useimpien muiden sillikalojen tapaan pintavesissä valtavina parvina. Se siirtyy talveksi syvemmälle. Poikaset kasvavat jokisuiden murtovedessä,[3]
Menhaden (Brevoortia tyrannus) on pohjoisamerikkalainen sillien heimon kalalaji. Sen arvo ihmisravintona ei kuitenkaan ole yhtä suuri kuin sillin, koska sen liha on varsin öljyistä, mutta se on tärkeä osa valaiden, merilintujen ja haiden ruokavaliota. Sitä käytetäänkin yleensä syöttinä kalastuksessa. Lisäksi siitä tehdään kalajauhoa, kalaöljyä ja lannoitetta.
Brevoortia tyrannus
Le Menhaden de l'Atlantique (Brevoortia tyrannus), ou Alose tyran[2] (Québec), est une espèce de poissons pélagiques argentés de la famille des Clupeidae (les harengs). Il présente la particularité de se nourrir de plancton (en filtrant l'eau de mer).
L'espèce Brevoortia tyrannus a été initialement décrite en 1802 par le naturaliste américain Benjamin Henry Latrobe (1764–1820) sous le protonyme de Clupea tyrannus[1].
Brevoortia tyrannus se rencontre dans l'Atlantique ouest, depuis les côtes de la Nouvelle-Écosse au Canada, jusqu'à l'Indian River (Floride)Indian River (Floride), aux États-Unis[3]. Ce poisson est présent depuis la surface jusqu'à une profondeur de 50 m[3].
Brevoortia tyrannus peut mesurer jusqu'à 50 cm et sa maturité sexuelle est atteinte lorsqu'il mesure entre 18 et 32 cm[3].
En français l'espèce Brevoortia tyrannus est appelée Alose tyran, Menhaden ou Menhaden tyran[3].
Il se nourrit de plancton collecté dans la colonne d'eau en filtrant l'eau de mer.
C'est une espèce très grégaire qui se déplaçait en bancs très importants, dont certains faisaient jusqu'à 64 km de long. Ceci en fait une proie intéressante et facile pour la pêche industrielle. Cependant, ce comportement rend également l'espèce très facile à surexploiter.
Le menhaden était très abondant en Atlantique Nord. Il est en régression (voir graphique).
Ses populations connues sont en régression depuis le XXe siècle, accélérée depuis quelques décennies par l'extension de la pêche minotière.
Brevoortia tyrannus
Le Menhaden de l'Atlantique (Brevoortia tyrannus), ou Alose tyran (Québec), est une espèce de poissons pélagiques argentés de la famille des Clupeidae (les harengs). Il présente la particularité de se nourrir de plancton (en filtrant l'eau de mer).
Meinhaddur (fræðiheiti Brevoortia tyrannus) er fiskur af síldaætt. Hann er mikið notaður í bræðslu. Meinhaddur lifir á plöntusvifi og getur fullvaxinn fiskur síað allt að fjögur gallon af vatni á mínútu. Meinhaddur hreinsar sjó með að sía hann og stórar torfur af meinhaddi halda þörungablóma í skefjum. Fiskurinn er mikilvægur í vistkerfi sjávar því margir fiskar lifa á honum og hann heldur þörungamengun í skefjum. Meinhaddur hefur verið í miklu magni í Norður-Atlantshafi og heldur fiskurinn sig í stórum torfum sem geta verið 40 km langar.
Meinhaddur er vinsæll til beitu. Einkenni meinhadds er að fiskurinn rotnar hratt eftir að hann hefur verið veiddur og er hann því aðallega nýttur til bræðslu þ.e. í fiskimjöl, lýsi og áburðar. Fiskurinn framleiðir Omega 3 fitusýrur sem eru nýttar af þeim fiskum sem á honum lifa.
Möguleikar eru á að nota meinhadd til efnaiðnaðar því við vinnslu fisksins þá má einangra úr vinnsluvatninu yfirborðsvirkt prótein sem er öflugt bindiefni og bleytiefni og því gott til notkunar í lágum styrk. Þetta prótein er er virkt á svæðum milli olíu og vatns og er umhverfisvænt (niðurbrjótanlegt).
Meinhaddur (fræðiheiti Brevoortia tyrannus) er fiskur af síldaætt. Hann er mikið notaður í bræðslu. Meinhaddur lifir á plöntusvifi og getur fullvaxinn fiskur síað allt að fjögur gallon af vatni á mínútu. Meinhaddur hreinsar sjó með að sía hann og stórar torfur af meinhaddi halda þörungablóma í skefjum. Fiskurinn er mikilvægur í vistkerfi sjávar því margir fiskar lifa á honum og hann heldur þörungamengun í skefjum. Meinhaddur hefur verið í miklu magni í Norður-Atlantshafi og heldur fiskurinn sig í stórum torfum sem geta verið 40 km langar.
Meinhaddur er vinsæll til beitu. Einkenni meinhadds er að fiskurinn rotnar hratt eftir að hann hefur verið veiddur og er hann því aðallega nýttur til bræðslu þ.e. í fiskimjöl, lýsi og áburðar. Fiskurinn framleiðir Omega 3 fitusýrur sem eru nýttar af þeim fiskum sem á honum lifa.
Möguleikar eru á að nota meinhadd til efnaiðnaðar því við vinnslu fisksins þá má einangra úr vinnsluvatninu yfirborðsvirkt prótein sem er öflugt bindiefni og bleytiefni og því gott til notkunar í lágum styrk. Þetta prótein er er virkt á svæðum milli olíu og vatns og er umhverfisvænt (niðurbrjótanlegt).
Brevoortia tyrannus (Latrobe, 1802), conosciuto comunemente con il nome inglese di menhaden, è un pesce osseo marino appartenente alla famiglia Clupeidae.
Questa specie vive nell'Oceano Atlantico occidentale tra la Nuova Scozia e il nord della Florida. Effettua migrazioni stagionali da nord a sud[1].
Questa specie è pelagica costiera. Frequenta acque molto vicine alla costa in estate e si sposta a maggiori profondità nella stagione fredda. Forma consistenti aggregazioni nei pressi delle foci, i giovanili possono risalire i fiumi per tratti abbastanza lunghi.[1].
Ha un aspetto relativamente simile a quello della cheppia mediterranea ed europea. Ha bocca molto grande e corpo più alto rispetto alla specie europea[1].
Il colore è argenteo con riflessi dorati sui fianchi e dorso blu-verde. Dietro l'opercolo branchiale c'è un punto nero ben definito; 6 linee di puntini neri longitudinali percorrono i fianchi[1].
Misura mediamente 18-32 cm, la taglia massima è di 50 cm[1].
È una specie planctofaga che cattura le sue prede per filtrazione[1].
Si riproduce tutto l'anno nelle acque salmastre degli estuari. Le larve dapprima fanno vita planctonica in mare e, quando raggiungono circa 1 cm di lunghezza, migrano negli estuari[1].
Questa specie ha una grande importanza per la pesca commerciale lungo la costa est degli Stati Uniti d'America. Sebbene sia commestibile, solo una parte del pescato viene impiegata per l'alimentazione umana; la maggior parte è destinata alla produzione di olio di pesce e fertilizzanti.[1].
Brevoortia tyrannus (Latrobe, 1802), conosciuto comunemente con il nome inglese di menhaden, è un pesce osseo marino appartenente alla famiglia Clupeidae.
Brevoortia tyrannus is een straalvinnige vissensoort uit de familie van haringen (Clupeidae).[2] De wetenschappelijke naam van de soort is voor het eerst geldig gepubliceerd in 1802 door Benjamin Henry Latrobe.[3] Hij had de vis in 1797 aangetroffen in de rivier York (Virginia). Elke vis had in de mond een "insect" van ongeveer vijf centimeter, dat hij Oniscus praegustator noemde. Dit is de pissebed Olencira praegustator die parasiteert op Brevoortia-soorten.
B. tyrannus komt voor langs de Atlantische kust van Noord-Amerika, van Florida tot Nova Scotia. De vissen leven in grote scholen en voeden zich met plankton. Ze migreren jaarlijks in de lente naar het noorden en in de herfst naar het zuiden. Er wordt commercieel op gevist; de vis wordt hoofdzakelijk gebruikt voor de productie van visolie en vismeel. Boeren gebruikten de vissen als meststof.[4][5]
Bronnen, noten en/of referentiesBrevoortia tyrannus é uma espécie de peixe da família Clupeidae do Atlântico Norte. São encontrados em águas costeiras da Nova Escócia até o norte da Flórida. Eles são comuns na baía de Chesapeake. Nadam em grandes grupos que estratificados por tamanho e idade ao longo da costa. Peixes mais jovens e menores são encontrados na Baía de Chesapeake e no litoral sul, enquanto os mais velhos e maiores são encontrados ao longo da costa norte.[1]
Brevoortia tyrannus é uma espécie de peixe da família Clupeidae do Atlântico Norte. São encontrados em águas costeiras da Nova Escócia até o norte da Flórida. Eles são comuns na baía de Chesapeake. Nadam em grandes grupos que estratificados por tamanho e idade ao longo da costa. Peixes mais jovens e menores são encontrados na Baía de Chesapeake e no litoral sul, enquanto os mais velhos e maiores são encontrados ao longo da costa norte.
Atlantisk menhaden (Brevoortia tyrannus) är en art i familjen sillfiskar.
En långsträckt fisk, med en avlång men tämligen hög kropp[2] som är ihoptryckt från sidorna och har ett kraftigt huvud med en stor mun, samt en kraftigt urnypen stjärtfena. Ryggen är blå- till grönaktig, övergående till silverfärg på nedre delen av kroppen.[3] Längs sidornas mitt kan kroppsfärgen ha en brunglänsande anstrykning.[4] Bröstfenorna är rundade, vilket skiljer den från den nära släktingen B. gunteri, tillsammans med det färre antalet fjäll (B. gunteri har 60 till 77 längs sidlinjen, medan denna art har mellan 42 och 48)[2]. Bakom övre delen av gällocket har den en stor, mörk fläck, och längs sidorna har den flera liknande, men mindre fläckar.[3] Arten kan bli upp till 50 cm lång.[4]
Den atlantiska menheden är en pelagisk stimfisk, som lever i kustnära vatten under sommaren, men drar sig ut mot djupare vatten till hösten.[2] Arten kan gå ner till ett djup av 50 m. Födan består av plankton som den filtrerar med sina gälräfständer, både växtplankton som dinoflagellater och djurplankton som havsborstmaskar och små kräftdjur samt detritus.[4]
Arten kan leka under hela året. De två viktigaste fortplantningsperioderna infaller emellertid under våren (mars till maj) och hösten (september till oktober). Vanligtvis sker leken i flodernas tidvattensområden.[5] Larverna är pelagiska, och antas tillbringa omkring en månad på djupare vatten, innan de återvänder till de kustnära områden i vilka de kläcktes.[4]
Den atlantska menheden finns längs Nordamerikas atlantkust från Nova Scotia i Kanada till mellersta Floridas västkust.[4]
Det bedrivs ett omfattande fiske på atlantisk menheden, framför allt i USA.[2]. Den används framförallt till fiskolja, fiskmjöl och gödsel, men saluförs även som människoföda i färsk, saltad, rökt och konserverad form.[4]
Atlantisk menhaden (Brevoortia tyrannus) är en art i familjen sillfiskar.
Cá mòi dầu Đại Tây Dương (Danh pháp khoa học: Brevoortia tyrannus) là loài cá ánh bạc trong Họ Cá trích (Clupeidae). Nó là một loài cá ăn các sinh vật phù du bị bắt bằng hình thức lọc nước và ăn lấy sinh vật phù du. Cá trưởng thành có thể lọc tối đa bốn lít nước một phút và chúng đóng một vai trò quan trọng trong việc làm sạch nước biển. Chúng cũng góp phần giảm tải hiện tượng thủy triều đỏ chết người.
Cá mòi dầu có lịch sử được sử dụng như một loại phân bón cho cây trồng. Có khả năng là cá mòi dầu là cá Squanto đã được những người hành hương chôn cùng với hạt giống trồng tươi làm phân bón. Các ứng dụng khác cho cá mòi dầu bao gồm: thức ăn cho động vật, mồi cá, dầu cho người tiêu dùng, dầu cho các mục đích sản xuất dầu như một nguồn nhiên liệu. Nhiều khẳng định rằng cá mòi dầu không ăn được nhưng nó vẫn là thực phẩm cho những người nghèo
Cá mòi dầu có số lượng lớn ở miền Bắc Đại Tây Dương từ Nova Scotia, Canada đến trung tâm Florida, Hoa Kỳ, mặc dù sự hiện diện của chúng trong vùng biển phía Bắc đã giảm trong thế kỷ 20. Chúng bơi trong các khối cầu cá lớn đến 40 dặm (64 km). Chúng là con mồi quan trọng đối với một loạt các động vật ăn thịt bao gồm cá tuyết, cá tuyết chấm đen, cá bơn, cá thu, cá kiếm, cá ngừ.
Các cá mòi dầu Đại Tây Dương được sử dụng phổ biến như mồi sống hay đã chết. Chúng sử dụng chủ yếu để sản xuất bột cá, dầu và phân bón. Trong những năm đầu của Hoa Kỳ, cá mòi dầu Đại Tây Dương đã được thu hoạch bằng hàng ngàn tàu của ngư dân. Từ đó số lượng cá mòi dầu dần cạn kiệt. Ngày nay đã có nhiều quy định về việc đánh bắt loài cá này cho hợp lý.
Cá mòi dầu Đại Tây Dương (Danh pháp khoa học: Brevoortia tyrannus) là loài cá ánh bạc trong Họ Cá trích (Clupeidae). Nó là một loài cá ăn các sinh vật phù du bị bắt bằng hình thức lọc nước và ăn lấy sinh vật phù du. Cá trưởng thành có thể lọc tối đa bốn lít nước một phút và chúng đóng một vai trò quan trọng trong việc làm sạch nước biển. Chúng cũng góp phần giảm tải hiện tượng thủy triều đỏ chết người.
Является объектом коммерческого промысла и спортивного рыболовства. Более 90% уловов приходится на США. Промысел ведётся сейнерами, с помощью различных сетей. Из атлантического менхэдена производят рыбную муку и вырабатывают жир[7].
Является объектом коммерческого промысла и спортивного рыболовства. Более 90% уловов приходится на США. Промысел ведётся сейнерами, с помощью различных сетей. Из атлантического менхэдена производят рыбную муку и вырабатывают жир.
