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Menhaden muddle, part 1.

[This is the first in a five-part series on the issue of menhaden depletion by Charles Hutchinson. For more background information, check out The Most Important Fish in the Sea. --Ed.] This column will be the first in a series describing the increasingly serious problem of a declining stock of menhaden. First order of business is to define the problem. While that ought to be simple and straightforward, it is anything but. In reality there are several problems when combined have a significant effect on East Coast fisheries now and is getting more serious as time passes. The overriding physical problem is the abundance of menhaden on a coastwide basis is declining. The extent of decline is such that the available biomass now is insufficient to meet the needs of a bait fishery, a reduction fishery, a variety of predator finfish, a variety of fish eating birds, and last, but not least, filtration capacity to reduce nutrients in the Chesapeake Bay waters. Regulation of the menhaden harvest is the responsibility of the Atlantic States Marine Fisheries Commission (ASMFC). They have failed to properly assess the needs for menhaden jn relation to the stock abundance. More about the ASMFC in an upcoming article. It is doubtful that many people involved in saltwater fishing know that there is a problem and those not along the coast have no interest in the issue. For at least a decade or more, the official document on the health of the menhaden stock known as the stock assessment has declared the stock as “not overfished and overfishing is not occurring”. This permits the ASMFC to declare that there is no problem with menhaden abundance hence no management action is required based on the best available science. The trouble here is that the stock assessment is not necessarily the best available science and it is by no means the only available science that concludes that there is a problem. The stock assessment tool box is composed of a complex computer model into which data on fish caught, natural mortality and other factors and estimates are fed to obtain an estimate of abundance. The reference points on which to judge condition of abundance have to do with reproductive capacity, not biomass. Since the model is driven primarily by the catch at Omega’s Reedville reduction factory, what the output is telling us is that there is sufficient stock to cover the needs of the reduction fishery with a safety margin. It does not deal effectively with the other needs for menhaden. The stock assessment team is responsible to and controlled by the ASMFC. Up until the 2009 stock assessment there has been a perceived unwillingness to make changes in the stock assessment process. This year a change in the mortality factor ( due to including more data on predator effects) has resulted in a preliminary report that the stock is on the brink of overfishing. Only three species of predator fish were included ( striped bass, bluefish and weakfish). Remember that menhaden migrate up and down the coast and in Federal as well as State waters and therefore are the target of a variety of ocean fish such as king mackerel, dolphin, and tuna to name a few whose appetites are not even considered in the stock assessment. If they were, there can be no doubt that overfishing is occurring. What will the Menhaden Management Board do now? Our next article will deal with the ASMFC and the political aspects of the Menhaden Issue.