October 24, 2012 — The following is an excerpt for the Marine Fish Conservation Network's FishHQ blog.
It’s crunch-time in the years-long battle to save what many people call the most important fish in the sea: Atlantic menhaden.
Anecdotal accounts of this odd oily fish indicate that they once swarmed up and down the east coast in huge schools and in numbers unimaginable to us today. Even more recently, scientific studies have shown that menhaden have declined 86% in the last 25 years, and that they have been exploited at too high a rate for at least 50 years. Half a century!
These fish used to be the main food for dozens of popular food and game fish like striper and bluefish. They’re not widely know as good eatin’, although I have a neighbor named Cornbread who swears by menhaden and mayonnaise sandwiches. No joke. He says everybody used to eat them because they were so abundant and easy to catch. Cornbread’s culinary proclivities aside, these forage fish are an integral part of the marine ecosystem, transforming the plants they eat into a moving fish feast.
So what’s the problem, you ask? Well, the problem is that Cornbread can’t go out and catch the filling for his sandwiches like he used to. And more importantly, critical recreational populations like stripers are being starved by menhaden’s declining numbers. Or to answer the question in another way, the problem is big, it’s powerful, and it has a name: it’s Omega Protein Inc.
Omega and its shareholders make a lot of money turning menhaden into lipstick, swine feed, and fish oil. For years, as recreational fishermen and local communities observed signs to the contrary, Omega claimed that the fishery was in fabulous shape. So, no regulations necessary, right? When a 2010 assessment once again proved their optimism to be unfounded, Omega wasn’t about to realign their business operations to the reality on the water. Instead, they hired scientists and lobbyists to influence, cajole, and filibuster the science-based management process.
But something inspiring has happened in response. A grassroots movement led by recreational anglers has emerged, opposing Omega’s efforts to dictate the management of menhaden to serve its own ends. Fishermen from all over the country have led a massive push to return the menhaden fishery to a sustainable level, while also accounting for the needs of predator species like striped bass.
Analysis: In a recent post on the Marine Fish Conservation Network’s FishHQ blog, Sera Drevenak relied on information provided by organizations other than her own, resulting in the inclusion of several misleading statistics in her article, “Menhaden’s moment of truth.” By relying on these statistics, the posting leaves the reader with an inaccurate characterization of the menhaden fishery.
The posting claims “scientific studies have shown that menhaden have declined 86% in the last 25 years, and that they have been exploited at too high a rate for at least 50 years.” The claim, frequently repeated elsewhere, that the menhaden population has decreased by almost 90 percent over the last quarter-century is based on a selective reading of menhaden biomass statistics; it misses the fluctuations in menhaden biomass that have occurred over the 50-plus years of available data.
These fluctuations are based on the strength of menhaden recruitment (the number of menhaden that are born), which will vary from year to year and is influenced by a number of factors, perhaps most importantly environmental conditions. The beginning of the period cited, the early 1980s, was a period of strong menhaden recruitment influenced by favorable environmental conditions, leading to high biomass. Since the early 1980s, environmental conditions have been much less favorable, resulting in lower recruitment and subsequently lower biomass. Fluctuations in environmental conditions lead to fluctuations in recruitment, which is reflected in the available data on the fishery: periods of high recruitment, like the late 1970s and early 1980s, are followed by periods of higher biomass, while periods of low recruitment, like the mid-to-late 1960s and today, are followed by periods of lower biomass.
The relationship between menhaden and climatic and environmental conditions is recognized by NOAA, which, on its Menhaden Fact Page, states, “menhaden recruitment appears to be independent of fishing mortality and spawning stock biomass, indicating environmental factors may be the defining factor in the production of good year classes.” The Atlantic States Marine Fisheries Commission (ASMFC) similarly concluded in its 2010 stock assessment that fluctuations in menhaden abundance may be “almost entirely driven by non-fishery sources.”
The blog post similarly exaggerates when with the statement, “Omega claimed that the fishery was in fabulous shape. So, no regulations necessary, right? When a 2010 assessment once again proved their optimism to be unfounded, Omega wasn’t about to realign their business operations to the reality on the water.” The 2010 menhaden assessment concluded that menhaden were experiencing overfishing, but were not overfished. This means that the fishery exceeded the mortality limit set by the ASMFC (overfishing), but that the stock’s fecundity (the number of eggs produced) was higher than the ASMFC’s threshold (overfished). Put simply, the assessment concluded that the stock was producing enough eggs to sustain itself, regardless of fishing pressure.
While overfishing did occur in the last year covered by the assessment (2008), it was slight, only .4 percent over the overfishing threshold. It was also only the second time in the last 15 years recorded by the assessment (1993-2008) that overfishing occurred. Similarly, the 2010 assessment concluded that the stock was producing eggs at almost twice the level at which the stock would be considered overfished. The picture of the fishery provided by the 2010 assessment–one where there is no recent pattern of overfishing and the stock is not overfished–is much different than the conclusions that Ms. Drevenak draws from it.
Ms. Drevenak also writes that "critical recreational populations like stripers are being starved by menhaden's declining numbers." However, this is not clearly the case given the available data on striped bass diet. Striped bass are opportunistic predators, and consume a variety of prey species depending on their availability and location. The 2010 annual report of the Chesapeake Bay Multispecies Monitoring and Assessment Program noted that bay anchovies, small crustaceans, and worms are all significant parts of the striped bass diet in addition to menhaden. Given the variety of variable nature of striped bass diets, it is not likely that they are dependent on any one single food source for survival.
All of the available data on menhaden present a situation that is much less dire than is characterized in Ms. Drevenak’s article. While menhaden remain an economically and ecologically important species, the management actions Ms. Drevenak advocates will unnecessarily impact the many people on the Chesapeake and the East Coast who depend on this vital fishery.