On a bright morning in May, a calm Chesapeake Bay glitters in the sun, an expanse of blue, the nation's largest and once most productive estuary. A sudden commotion shatters the serenity: Dozens of gulls swoop toward the 135-foot ship Reedville, and the water beneath the boat begins to churn and froth. With two smaller boats at its side, the Reedville encloses a school of fish in a stiff black purse seine net. With practiced efficiency, workers onboard hoist a vacuum pump into the net and suck tens of thousands of small silvery fish out of the water. It looks like an unusual way to catch fish; it's all the more unusual when you realize that this particular industrial catch is actually banned by every state on the East Coast. Every state, that is, save for one: Virginia.
The fish going up the tube are Atlantic menhaden, known to ocean ecologists as the "breadbasket of the ocean," though some prefer to call them "the most important fish in the sea." Because there's money to be made, menhaden, all the fish that rely on them for food, and the entire ocean ecosystem are in trouble.
Found in estuarine and coastal waters from Nova Scotia to Florida, menhaden are oily, bony, and inedible to humans, which is why you've probably never heard of them. But their nutrient-packed bodies are a staple food for dozens of fish species you have heard of, as well as marine mammals and sea birds. Located near the bottom of the food chain, menhaden are the favored prey for many important predators, including striped bass and bluefish, tuna and dolphin, seatrout and mackerel.
Out on the bay, the vacuum pump on the Reedville removes 45,000 menhaden from the water. This is a small catch for a boat that routinely takes multiple schools, each of which can contain as many as a million members, stored in a giant hold below deck. There, they will wait for the ship to return to its namesake, Reedville, a remote town on Virginia's northern neck peninsula, where they will be cooked, ground up, and sold. This is the "menhaden reduction" process, the basis for a lucrative industry controlled, on the East Coast, by exactly one company: Omega Protein, Inc.
The same oily property that makes menhaden so valuable to marine life can also be used for aquaculture and livestock feed, pet food, oil for paints and cosmetics, and as a component in dietary supplements. Omega Protein's annual harvest is worth more than $168 million. Revenues for 2011 are projected at $218 million. Because of Omega Protein, Reedville is the third largest commercial fishing port in the United States.
Some scientists believe that menhaden could be a partial solution to pollution and the oxygen-depleted areas of water called, bluntly, "dead zones." In these zones, pollution-related algae blooms use up the oxygen in the water, making it difficult for other species to live; it's a particular problem in estuaries like the Chesapeake Bay and the Long Island Sound, where menhaden were once plentiful. Menhaden are filter feeders, swimming with their mouths open and straining phytoplankton (algae) and other particles with their gills. While the exact content of what menhaden filter varies by location and season, it is clear that menhaden have been removing damaging particles from our waters since time immemorial.
"Menhaden are the main herbivore in the ocean that eat phytoplankton, and without them, we have a problem," says Bill Goldsborough, senior scientist at the Chesapeake Bay Foundation.
Goldsborough and other fisheries scientists are concerned about diminishing numbers of menhaden along the Atlantic Coast. Recent evidence shows that menhaden stocks are down 88 percent in the last 25 years, to a record low — from 160 billion fish to 20 billion. Atlantic menhaden harvesters have regularly overfished their target limit: 32 of the last 54 years, according to a 2010 stock assessment by the Atlantic States Marine Fisheries Commission, the regulatory agency in charge of managing the sustainability of forage species like menhaden.
One sign that points to the scale of the problem is that species like striped bass that normally feed on menhaden are displaying symptoms of malnourishment and disease. Seatrout are near their lowest population point on record, in part because of a lack of menhaden. When faced with the loss of both seatrout and menhaden as food, striped bass have been turning to other cherished delicacies. "Striped bass will feed on blue crabs and lobsters when they can't get enough menhaden. We are seeing increased mortality of juvenile lobster and blue crabs," Goldsborough says.
Scientists say Omega Protein removes menhaden at a rate that makes it nearly impossible for the fish to provide the valuable ecosystem services that give them their vaunted title. The annual removal of adult fish is 65 percent or higher, making it unlikely that an adult menhaden will spawn more than once, if at all. Scientists say that this affects the health and sustainability of our natural resources: "[Overfishing] is certainly affecting menhaden, not just in Maryland but coastwide, and therefore it affects the predator populations as well that rely on menhaden. There is no doubt about that. We are competing with the predators," says Dr. Alexei Sharov, head of the stock assessment program at Maryland's Department of Natural Resources Fisheries Service.
Read the full article at Salon
Analysis:
The article makes several incorrect and misleading claims about the menhaden reduction fishery, the sustainability of menhaden fishing, and the potential ecological effects. The article is based on the premise that menhaden are being fished at an unsustainable rate, and thatthis overfishing is having an environmental impact. However, there is significant evidence that the menhaden population in the Chesapeake Bay is not overfished. The Atlantic States Marine Fisheries Commission (ASMFC), in its most recent stock assessment, concluded that the menhaden population was not overfished. In the past ten years, overfishing had only occured once in the past ten years.
In addition to overstating the impact of fishing on the menhaden population, the article also overstates their ecological role. Referring to menhaden as filter feeders, the article claims menhaden are essential to cleaning the Bay and that the health of the Bay is suffering due to lack of menhaden. The Virginia Institute of Marine Science (VIMS) recently conducted a study on menhaden's role as filter feeders. They concluded that adult menhaden, which are the group harvested by Omega, eat very little phytoplankton, and remove very little phytoplankton or nitrogen from the water.
The article is also incorrect in blaming poor health in striped bass on the level of menhaden in the Bay. But, as part of their ongoing ChesMMAP study, VIMS has analyzed the diets of several species of fish, and menhaden only make up a small percentage of the diet of many species. For example, they have been found to make up as little as 9.6% of striped bass diet, even though the exact number will fluctuate given location of the bass or prevalence of other feed species.