Atlantic menhaden (Brevoortia tyrannus) are found in estuarine and coastal waters from northern Florida to Nova Scotia and serve as prey (food) for many fish, sea birds and marine mammals. Adult and juvenile menhaden form large, near-surface schools, primarily in estuaries and nearshore ocean waters from early spring through early winter. By summer, menhaden schools stratify by size and age along the coast, with older and larger menhaden found farther north. During fall-early winter, menhaden of all sizes and ages migrate south around the North Carolina capes to spawn.
Sexual maturity begins just before age three, with major spawning areas from the Carolinas to New Jersey. Most spawning occurs offshore (20-30 miles) during winter. Buoyant eggs hatch at sea and larvae are carried into estuarine nursery areas by ocean currents. Juveniles spend most of their first year of life in estuaries, migrating to the ocean in late fall. Adult and juvenile menhaden migrate south in fall-winter, and adult menhaden migrate north in spring.
Menhaden feed by straining plankton from the water, their gill rakers forming a specialized basket to efficiently capture tiny food. They provide a link between primary production and higher organisms by consuming plankton and providing forage (food) for species such as striped bass, bluefish and weakfish, to name just a few.
Schooling Atlantic menhaden. Photo ©ASMFC.
The Atlantic menhaden commercial fishery has two major components, a reduction sector that harvests fish for animal feed and fish oil, and a bait sector that supplies bait to other commercial and recreational fisheries. Total commercial landings averaged 464 million pounds from 2008-2012, with approximately 77% harvested by the reduction fishery and 23% harvested for bait purposes.
The reduction fishery, named because it processes the whole fish into fish meal, fish oil and fish solubles, first began in New England during the early 1800s and spread south after the Civil War allowing the fishery to expand. Major technological innovations led to further expansion of the fishery coastwide. As a result, landings and fishing effort increased from 1940 through the late 1950s, declined precipitously during the 1960s when the population was overfished, and then increased significantly during the late 1970s and early 1980s. Currently, there is only one remaining reduction plant in operation on the Atlantic coast processing Atlantic menhaden into fishmeal and oil. The fishmeal is used as fertilizer and animal feed, while fish oil is used in many commercial products and in omega-3 supplements for human health. Most of the catch occurred within the Chesapeake Bay, in Virginia waters, and in ocean waters off New Jersey.
The bait fishery has become increasingly important from North Carolina to New England, supplying fishermen with bait for popular commercial (e.g., American lobster and blue crab) and sport fisheries (e.g., striped bass, bluefish). In recent years, the majority of bait landings has been harvested from Virginia and New Jersey waters, followed by Massachusetts and Maryland. Between 2001 and 2010, the percent of total menhaden landings attributed to the bait fishery rose from 13% to a high of 25% in 2008. Currently, bait harvest is approximately 23% of the total menhaden harvest.
Recreational landings of Atlantic menhaden are estimated to represent less than 1% of the total landings of the species. During the last decade (2001-2012), there was an average annual recreational catch of 589,000 pounds of menhaden.
Both the 2010 benchmark stock assessment and the 2012 stock assessment update indicate that Atlantic menhaden are experiencing overfishing, but it is unknown if the stock is overfished. The uncertainty in the overfished determination comes from conflicting results of sensitivity runs explored in the 2012 assessment update. The next benchmark stock assessment is scheduled for peer review in December of 2014.
Atlantic menhaden are currently managed under Amendment 2 to the Interstate Fishery Management Plan (FMP) for Atlantic Menhaden. Approved in December 2012, Amendment 2 establishes a 170,800 MT total allowable catch (TAC) beginning in 2013 and continuing until completion of, and Board action on, the next benchmark stock assessment, scheduled for 2014. The TAC represents a 20% reduction from the average of landings from 2009-2011 and an approximately 25% reduction from 2011 levels. The Amendment also establishes new biological reference points for biomass based on maximum spawning potential (MSP), with the goal of increasing abundance, spawning stock biomass, and menhaden availability as a forage species. These new abundance points use the same metric (e.g., MSP) as that used for define overfishing (fishing mortality target of F30%MSP) and (fishing mortality threshold of F15%MSP).
The Amendment allocates the TAC on a state-by-state basis based on landings history of the fishery from 2009-2011; allocation will be revisited three years after implementation. Further, it reduces the Chesapeake Bay reduction fishery harvest cap by 20% (this is an adjustment of cap which was in place since 2006). States will be required to close their fisheries when the state-specific portion of the TAC has been reached; any overages must be paid back the following year.
Prior to Amendment 2, the Chesapeake Bay reduction fishery harvests had been managed by an annual cap of 109,020 metric tons, a number derived from the average of harvests from 2001 – 2005. This cap was in place from 2006 – 2012.
The Board also continues to place a high priority on advancing the development of ecosystem reference points using a multispecies modeling approach. Ecosystem reference points are expected to address the forage needs of menhaden’s predator species, including striped bass, weakfish, and bluefish. This work is anticipated to take a few years.