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Menhaden

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Menhaden
Brevoortia patronus
Brevoortia patronus
Scientific classificationEdit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Superorder: Clupeomorpha
Order: Clupeiformes
Groups included
Cladisticallyincluded but traditionally excluded taxa

all other genera in the familiesClupeidaeandAlosidae

Menhaden
Gulf menhaden,Brevoortia patronus
Atlantic menhaden,Brevoortia tyrannus
Pacific menhaden,Ethmidium maculatum

Menhaden,also known asmossbunkerandbunkerand "the most important fish in the sea",[1]areforage fishof the generaBrevoortiaandEthmidium,two genera ofmarine fishin the orderClupeiformes.Menhadenis a blend ofpoghaden(pogyfor short) and anAlgonquianword akin toNarragansettmunnawhatteaûg,derived frommunnohquohteau( "he fertilizes" ), referring to their use of the fish asfertilizer.[2]It is generally thought thatPilgrimswere advised by Tisquantum (also known asSquanto) to plant menhaden with their crops.[2]

Description[edit]

Menhaden are flat and have soft flesh and a deeply forked tail. They rarely exceed 15 inches (38 cm) in length, and have a varied weight range.Gulf menhadenandAtlantic menhadenare small oily-fleshed fish, bright silver, and characterized by a series of smaller spots behind the mainhumeral spot.They tend to have larger scales than yellowfin menhaden and finescale menhaden. In addition, yellowfin menhaden tail rays are a bright yellow in contrast to those of the Atlantic menhaden.

Taxonomy[edit]

Recent taxonomic work usingDNAcomparisons have organized the North American menhadens into large-scaled (Gulf and Atlantic menhaden) and small-scaled (Finescale and Yellowfin menhaden) designations.[3]

The menhaden consist of two genera and seven species:

Distribution[edit]

Ecology[edit]

Menhaden arefilter feedersthat travel in large, slow-moving, and tightly packedschoolswith open mouths. Filter feeders typically take into their open mouths "materials in the same proportions as they occur in ambient waters".[4]Menhaden have two main sources of food:phytoplanktonandzooplankton.A menhaden's diet varies considerably over the course of its lifetime, and is directly related to its size. The smallest menhaden, typically those under one year old, eat primarily phytoplankton. After that age, adult menhaden gradually shift to a diet comprised almost exclusively of zooplankton.[5]

Menhaden are omnivorous filter feeders, feeding by strainingplanktonandalgaefrom water. Along withoysters,which filter water on the seabed, menhaden play a key role in thefood chainin estuaries and bays.[6]Atlantic menhaden are an important link between plankton and upper level predators. Because of their filter feeding abilities, "menhaden consume and redistribute a significant amount of energy within and betweenChesapeake Bayand other estuaries, and the coastal ocean. "[7]Because they play this role, and their abundance, menhaden are an invaluable prey species for many predatory fish, such asstriped bass,bluefish,mackerel,flounder,tuna,drums,andsharks.They are also a very important food source for many birds, includingegrets,ospreys,seagulls,northern gannets,pelicans,andherons.

In 2012, theAtlantic States Marine Fisheries Commissiondeclared that theAtlantic menhadenwasdepleteddue tooverfishing.The decision was driven by issues with water quality in theChesapeake Bayand failing efforts to re-introduce predator species, due to lack of menhaden on which they could feed.[2]

Menhaden are crucial not only because of their keystone species-status in the food web, but also because of their ecological services. The way menhaden filter feed on phytoplankton helps to mitigate toxic algal blooms. These algal blooms, which are often detrimental to a number of fish, bird, and marine mammal species, create hypoxic conditions. The phytoplankton being preyed upon are photosynthetic organisms, converting sunlight into energy which is then transferred to menhaden and then to bigger species of fish or other larger marine organisms such as birds or mammals. The consequence of this behavior is that if menhaden are eliminated or significantly decreased, there are limited means of energy transfer among trophic levels – making menhaden a true keystone species with ecological services that are invaluable to humans.

Habitat[edit]

Menhaden are a pelagic schooling fish that migrate inshore during the summer and off-shore in the winter months. The juvenile and larval menhaden migrate to shore and inland waterways through currents during summer months to grow while feeding on the phytoplankton and eventually zooplankton once they have matured. Commercially caught menhaden have been recorded in waters of around 5 to 24 ‰, as well as in hypersaline waters around 60 ‰.[8]

Reproduction[edit]

Menhaden reproduce in open oceans externally, however, the female does not carry eggs with them during the process as they are released into the water column at the planktonic level as gametes and sperm. Currently, functional hermaphroditism is unknown to the species and identification of sex of the individual organism cannot be determined externally due to the lack of accessory reproductive organs.[9]These fish breed during the winter months through December to March and the eggs and juveniles navigate towards estuaries and inland waterways through tides and currents.[9]

Human use[edit]

Menhaden are not used directly for food. They areprocessedintofish oilandfish mealthat are used asfood ingredients,animal feed,anddietary supplements.[6]The flesh has a highOmega -3 fatcontent. Fish oil made from menhaden also is used as a raw material for products such aslipstick.[10]

Fisheries[edit]

According to theVirginia Institute of Marine Science(VIMS), there are two established commercial fisheries for menhaden. The first is known as areduction fishery.The second is known as a bait fishery, which harvests menhaden for the use of both commercial and recreational fishermen. Commercial fishermen, especiallycrabbersin the Chesapeake Bay area, use menhaden to bait their traps or hooks. The recreational fisherman use ground menhaden chum as a fish attractant, and whole fish as bait. The total harvest is approximately 500 million fish per year.[10]Atlantic menhaden are harvested usingpurse seines.

Omega Protein– a reduction fishery company with operations in the northwest Atlantic and the Gulf of Mexico – takes 90% of the total menhaden harvest in the United States.[10]In October 2005, theAtlantic States Marine Fisheries Commission(ASMFC) approved an addendum to Amendment 1 of the Interstate Fishery Management Plan for Atlantic Menhaden, which "established a five-year annual cap on reduction fishery landings in theChesapeake Bay",imposing a limit on reduction fishery operations for 2006–2010. In November 2006, that cap was established at 109,020 metric tons;[11]this cap remained in place until 2013.[12]

In December 2012, in the face of thedepletionof Atlantic menhaden, the ASMFC implemented another cap, effective in 2013 and 2014, for the Chesapeake Bay, this time at 87,216 metric tons, as well as a total allowable catch (TAC) of the species of 170,800 metric tons, a 20% reduction from the 2009–2011 average.[13][14]The TAC was subsequently raised for 2015 and 2016 to 187,880 metric tons.[15]The cap in the Chesapeake Bay was further lowered in November 2017 to 51,000 metric tons, but this came alongside a higher TAC of 216,000 metric tons.[16][17]Omega Protein has been openly critical of these caps.[14][17]

Uses for menhaden oil[edit]

Despite not being a popular fish for consumption, menhaden oil has many uses not only for humans but also for other animals. One element of menhaden oil is that it is high in Omega -3 fatty acids. This molecule helps with lowering blood pressure, fi xing abnormal heartbeats, reducing the chance of a heart attack or stroke, and other health benefits. It is due to this that menhaden oil can be used in supplements to help with the previously mentioned issues.[19]

One way that menhaden oil benefits animals is seen in chickens. When menhaden oil was given to chickens in their feed, they had a lower chance offatty liver disease.[20]This was because of menhaden oil's high Omega -3 fatty acid content which took the place of Omega -6 fatty acid which is not as beneficial to animals. Another animal that benefits from Omega -3 in menhaden oil is guinea pigs. When given menhaden oil in feed guinea pigs were shown to have a longer life span.[21]

Risks of overfishing[edit]

Bay-wide Geometric Mean Catch per Haul in the Chesapeake Bay of Atlantic Menhaden reported by the Chesapeake Bay Foundation in 2019.[22]

According to the Chesapeake Bay Foundation, menhaden are the most important fish in the Bay.[23]This is because they are a food source for many commercial important species like striped bass. They also manage the algal bloom occurrences in the Bay because they eat phytoplankton. Decreases in menhaden populations could also leave striped bass vulnerable to disease. In the past 20 years, the number of juvenile menhaden produced in the Chesapeake Bay have been decreasing (Refer to Atlantic Menhaden Graph on bay-wide mean catch per haul).[23]

This is believed to be due to the overfishing of menhaden for their fish oil. This could seriously disrupt the food chain. In response, the Atlantic States Marine Fisheries Commission (ASMFC) put a cap on the Atlantic menhaden harvest in October 2020. This 10% cut to the harvest is the first to ever be seen for menhaden coast-wide.[24]It also was the first vote to consider benchmarks known as "ecological reference points".[23]This allows managers to account for a species role in the food chain when setting catch limits. This is different from the "single-species stock assessments" that were previously used which only accounted for the demand from the fishing industry rather than the demand from the food web.[23]This cut to the harvest established a quota of 194,400 metric tons of menhaden for the 2021–2022 fishing season.[24]It is the hope that this cut will allow menhaden to fulfill their role in the ecosystem while keeping the commercial fishery alive.

Cultural significance[edit]

After menhaden had been identified as a valuable alternative towhale oilin the 1870s, the menhaden fishery on the Chesapeake was worked by predominantly African-American crews on open boats haulingpurse seines.The men employedsea chantiesto help synchronize the hauling of the nets. These chanties pulled from West African, blues, and gospel sources and created a uniquely African American culture of chanty singing. By the late 1950s, hydraulic winches replaced the large crews of manual haulers, and the menhaden chanty tradition declined.[20]

Notes[edit]

  1. ^Franklin, H. (2007).The Most Important Fish in the Sea.Island Press.ISBN978-1-59726-124-1.
  2. ^abcConniff, Richard(7 December 2012)."The Oiliest Catch".Conservation Magazine.University of Washington.Archivedfrom the original on 31 January 2016.Retrieved18 January2013.
  3. ^Anderson, Joel D. (2007)."Systematics of the North American menhadens: molecular evolutionary reconstructions in the genus Brevoortia (Clupeiformes: Clupeidae)"(PDF).Fishery Bulletin.105(3): 368–378. Archived fromthe original(PDF)on 21 July 2011.Retrieved10 February2011.
  4. ^VanderKooy, Steven J.; Smith, Joseph W., eds. (March 2002).The Menhaden Fishery of the Gulf of Mexico, United States: A Regional Management Plan(PDF)(Report).Gulf States Marine Fisheries Commission.pp. 3–10.Archived(PDF)from the original on 3 March 2019.
  5. ^Friedland, Kevin D.; Lynch, Patrick D.; Gobler, Christopher J. (November 2011)."Time Series Mesoscale Response of Atlantic MenhadenBrevoortia tyrannusto Variation in Plankton Abundances ".Journal of Coastal Research.27(6): 1148–1158.doi:10.2112/JCOASTRES-D-10-00171.1.S2CID131569331.
  6. ^abTavee, Tom; Franklin, H. Bruce (1 September 2001)."The Most Important Fish in the Sea".Discover.Archivedfrom the original on 8 August 2018.
  7. ^"Maryland Department of Natural Resources".Dnr.state.md.us. 31 December 2012.Retrieved7 January2013.
  8. ^"FAO Fisheries & Aquaculture – Aquatic species".fao.org.Retrieved4 December2020.
  9. ^abReintjes, John W. (November 1969).FAO Species Synopsis No. 42: Synopsis of Biological Data on the Atlantic Menhaden,Brevoortia tyrannus(PDF).Food and Agriculture Organization of the United Nations(Report). Washington, DC: U.S. Department of the Interior, U.S. Fish and Wildlife Service, Bureau of Commercial Fisheries. Circular 320.Archived(PDF)from the original on 29 November 2020.Retrieved14 November2022.
  10. ^abcGreenberg, Paul(15 December 2009)."A Fish Oil Story".The New York Times.Archivedfrom the original on 7 February 2019.Retrieved10 February2011.
  11. ^Addendum III to Amendment 1 to the Interstate Fishery Management Plan for Atlantic Menhaden(PDF)(Report).Atlantic States Marine Fisheries Commission.November 2006. pp. 2–3.Archived(PDF)from the original on 8 April 2015.Retrieved24 March2019.
  12. ^Addendum IV to Amendment 1 to the Atlantic Menhaden Fishery Management Plan(PDF)(Report).Atlantic States Marine Fisheries Commission.November 2009. p. 3.Archived(PDF)from the original on 18 March 2019.
  13. ^Amendment 2 to the Interstate Fishery Management Plan for Atlantic Menhaden(PDF)(Report).Atlantic States Marine Fisheries Commission.December 2012. pp. 47, 55.Archived(PDF)from the original on 18 March 2019.
  14. ^abFairbrother, Alison (31 March 2013)."Omega Protein makes good on threat to cut jobs; but it doesn't have to".Bay Journal.Archivedfrom the original on 29 June 2017.
  15. ^Addendum I to Amendment 2 of the Atlantic Menhaden Interstate Fishery Management Plan(PDF)(Report).Atlantic States Marine Fisheries Commission.August 2016.Archived(PDF)from the original on 18 March 2019.
  16. ^Amendment 3 to the Interstate Fishery Management Plan for Atlantic Menhaden(PDF)(Report).Atlantic States Marine Fisheries Commission.November 2017. p. iii, v.Archived(PDF)from the original on 18 March 2019.
  17. ^abBittenbender, Steve (7 May 2018)."Omega Protein critical of ASMFC actions on Chesapeake menhaden".SeafoodSource.Archivedfrom the original on 24 March 2019.Retrieved24 March2019.
  18. ^abBased on data sourced from the relevantFAO Species Fact Sheets
  19. ^Hargis, P.S.; Van Elswyk, M.E.; Hargis, B.M (1 April 1991)."Dietary Modification of Yolk Lipid with Menhaden Oil".Poultry Science.70(4): 874–883.doi:10.3382/ps.0700874.ISSN0032-5791.PMID1908579.
  20. ^abAnderson, Harold (January–February 2000)."Menhaden Chanteys: An African American Maritime Legacy"(PDF).Maryland Marine Notes.18(1). College Park, Maryland:Maryland Sea Grant College:1–6.Archived(PDF)from the original on 24 March 2019.
  21. ^Mascioli, E A; Iwasa, Y; Trimbo, S; Leader, L; Bistrian, B R; Blackburn, G L (1 February 1989)."Endotoxin challenge after menhaden oil diet: effects on survival of guinea pigs".The American Journal of Clinical Nutrition.49(2): 277–282.doi:10.1093/ajcn/49.2.277.ISSN0002-9165.PMID2492743.
  22. ^"Atlantic Menhaden".cbf.org.Retrieved10 December2020.
  23. ^abcd"Atlantic Menhaden".cbf.org.Retrieved9 December2020.
  24. ^ab"Fisheries Panel Cuts Atlantic Menhaden Harvest by 10 Percent".cbf.org.Retrieved9 December2020.

References[edit]

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