Atlantic menhaden

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Atlantic menhaden
Brevoortia tyrannus1.jpg
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Clupeiformes
Family: Clupeidae
Subfamily: Alosinae
Genus: Brevoortia
Species: B. tyrannus
Binomial name
Brevoortia tyrannus
(Latrobe, 1802)

The Atlantic menhaden (Brevoortia tyrannus) is a silvery, highly compressed fish in the herring family, Clupeidae.[1]

Menhaden is a North American fish, which historically occurred in large numbers in the North Atlantic, ranging from Nova Scotia to central Florida, although their presence in northern waters has diminished in the 20th century.

Brevoortia tyrannus.jpg

They swim in large schools, some reportedly up to 40 miles (64 km) long. As a result of their abundance they are important prey for a wide range of predators including bluefish, striped bass, cod, haddock, halibut, mackerel, swordfish, and tuna.[2]

Atlatic menahden is a filter feeder living on plankton caught in midwater. Adult fish can filter up to four gallons of water a minute, and they play an important role in clarifying ocean water. They are also a natural check to the deadly red tide.[2]

Fisheries and management[edit]

Historical uses[edit]

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 thousand of ships of fishermen. 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.[3]

While many sources today claim that the menhaden is inedible, the fish were once consumed as sardines might be, or fried. Maine fisherman, 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.

Current fisheries[edit]

Menhaden catch for fishmeal industry

The Atlantic menhaden is popular for use as live or dead bait. The fish is notorious for its rapid deterioration when caught, as well as its bony and oily makeup. As a result, they are primarily used for the production of fish meal, oil and fertilizer. It went on to be used for this purpose on a large scale on farmland on the Atlantic coast, though this process was stopped after it was realized that the oily fish parched the soil.[2][4]

As of today, Omega Protein, a Houston, Texas-based company, has a virtual monopoly on the menhaden reduction industry in the United States.[5] Omega Protein operates mainly in Virginia and North Carolina due to the outlawing of purse-seining in all other Atlantic coast states.

Annual catch statistics for Atlantic menhaden 1950-2010

Management[edit]

Atlantic menhaden are managed by the Atlantic States Marine Fisheries Commission (ASMFC), which is an interstate agreement by the 15 Atlantic coast states. Within the organization exists an Interstate Fishery Management Plan that is designed to regulate the harvest.

Due to concerns the ASMFC in 2006 put a harvesting cap of 109,020 metric tons on the reduction fishery in the Chesapeake Bay for the next five years. Omega Protein has continued to abide by the harvesting cap and even elected to extend the cap for following two years.

In recent years the menhaden population is considered to be sustainable coastwide, though a possibility for a localized depletion exists in the Chesapeake Bay due to a concentrated harvest.[6]

ASMFC uses two biological reference points to measure the stock. To determine if the stock is overfished, the ASMFC uses a population fecundity (FEC) reference point. This measurement focuses on the number of mature eggs in the menhaden population to determine reproductive capability.

According to the ASMFC's 2010 stock assessment, menhaden are not overfished because the number of mature eggs was 99%of the target FEC and 198% of the threshold FEC.

Another measurement used by the ASMFC is a fishing mortality (F) target and threshold. The target F is set at 0.96 and the threshold F is set at 2.2. This measurement focuses on the highest amount of pressure that the menhaden stock can withstand. If fishing occurs beyond the target or threshold, management has the authority to intervene.

According to the ASMFC's 2010 stock assessment, overfishing of menhaden did occur in 2008 due to the F threshold reaching 2.28. The toe over the line in 2008 had ruined a 9 year streak (1999-2007) of no overfishing.

Environmental problems in the Chesapeake Bay[edit]

Dead zone[edit]

Tremendous algal blooms that starve the bay of sunlight and oxygen have been attributed to a diminished menhaden population due to the menhaden's important role as a filter feeder of algae and other phytoplankton. Significant malnutrition and disease in one of its primary predators, the striped bass, is also widespread in the Chesapeake.[5] Yet the Virginia Institute of Marine Science published an article which states that menhaden have "little net impact on Bay water quality" [7]

Striped bass[edit]

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.[8][9]

History of the names[edit]

  • Menhaden - comes from the Native American word munnawhatteaug which means "that which manures" (fertilizer). The Native Americans would use the menhaden to fertilize their crops.
  • American sardine - in the 1800s Americans would prepare and consume the menhaden like the European sardine.
  • Pogy- comes from the Native American word pauhagen or pookagan which holds the same meaning as Munnawhatteaug.
  • Bony-fish, hard-head- describes the structure of the fish.
  • White-fish- used to describe North American fresh-water fish.
  • Mossbunker- comes form the Dutch word Marsbanker that translates to horse mackerel, which is a similar looking fish found in the Netherlands. The Dutch colonists began reusing the name to describe the menhaden.
  • Bug-fish, bug-head - the name comes from the presence of a parasitic crustacean (Cymothoa pregustator) that is found in the mouth of the menhaden due to the fact that the menhaden swim with their mouth open.
  • Fat-back - used to describe the oily flesh found on the menhaden.
  • Yellow-tail, yellow-tailed shad, green-tail- used to describe the tint of the caudal fin.
  • Shad, alewife, and herring - terms representing the herring family have come to be used to describe the menhaden.

References[edit]

  1. ^ Froese, Rainer and Pauly, Daniel, eds. (2005). "Brevoortia tyrannus" in FishBase. 10 2005 version.
  2. ^ a b c H. Bruce Franklin (March 2006). "Net Losses: Declaring War on the Menhaden". Mother Jones. Archived from the original on 18 March 2006. Retrieved 21 February 2006.  Extensive article on the role of menhaden in the ecosystem and possible results of overfishing.
  3. ^ ASMFC 2005
  4. ^ George Brown Goode (1887). The Fisheries and Fishery Industries of the United States. Section V. History and Methods of the Fisheries. Washington, D.C.: U.S. Government Printing Office. 
  5. ^ a b H. Bruce Franklin (2007) The Most Important Fish in the Sea: Menhaden and America Island Press. ISBN 978-1-59726-124-1
  6. ^ ASMFC 2005
  7. ^ http://www.vims.edu/newsandevents/topstories/menhaden_water_quality.php
  8. ^ http://www.vims.edu/research/departments/fisheries/programs/multispecies_fisheries_research/data_products/chesmmap_reports/2009.pdf
  9. ^ http://www.fisheriessociety.org/mid-atlantic/Presentations_2010/08_Clark_Striped_bass_feeding_habits.pdf