THIS COLUMN is a request that you put on your best letter-writing hat, warm up your computer, get out your old typewriter or get a pad of nice stationery and a pen. Do whatever it takes to send letters to the people who need to listen. This appeal is especially aimed at fishermen, like me, who remember the good old days.
When my children were young, we caught big — I mean really big — blues just below and above the Chesapeake Bay bridge. I am talking about 12-pound fish caught on poppers. My personal biggest blue weighed 17 pounds and was caught in the lower bay.
Why did we catch them then and not now? Because of the lack of menhaden, also called bunker or mossbunker. There used to be a lot of them. The bluefish followed them up the bay. They are considered by marine biologists, the most important part of a rockfish's diet.
Today, scientific estimates place the population of menhaden at 8 percent of what it was before exploitation. Studies of rockfish diets say that menhaden comprise 8 percent of current striped bass diets. Historically, menhaden were as much as 70 percent of striper diets. They are also an important food source for weakfish, sharks, sea turtles, ospreys, pelicans and loons.
More than a few people in the know think that this lack of proper diet is what makes striped bass (also known as rockfish) susceptible to mycobacteriosis, which causes infected fish to slowly lose body mass and weight, and other diseases.
Watermen complain that rockfish are eating crabs. Well, sure, if you can't have ham and eggs, you eat cereal.
On the subject of eating, what menhaden eat positions them where they are in the food chain. Menhaden are filter feeders. They strain plankton, tiny plants and animals suspended in the water column. They convert the plankton into food for creatures higher in the food chain. It is natural.
What is unnatural and needs to be changed is the unrestrained harvesting of bunker by the fleets of factory ships that use airplanes to spot the schools. The schools of fish are encircled by large purse seine nets, then pumped into the ships and are processed to make fish oil, poultry food and other products.
Read the full article at the Frederick News Post.
Analysis: The article makes several misleading claims about the overall state of the menhaden fishery. The first is that the menhaden population is dangerously overfished. According to the ASMFC, not only is the menhaden fishery not overfished, but it has only experienced overfishing once in the last ten years. The article is correct in noting that menhaden are at 8% of their Maximum Spawning Potential (MSP). However, the article fails to note that, given the large number of eggs an individual menhaden lays, this has usually been sufficient to rebuild the population; MSP has rarely gone above 10% in the past 50 years. Currently, the menhaden fishery is meeting its target fecundity levels.
The article is also misleading in claiming an alleged lack of menhaden as being responsible for mycobacteriosis in sea bass. A recent survey of Chesapeake Bay marine life puts menhaden at around 9% of striped bass diet. However, bass diets are variable for reasons that have nothing to do with the commercial reduction fishery, such as water quality and location and prevalence of other prey species, as bass do not exclusively rely on one species for food. The cause of mycobacteriosis in bass is also more due to environmental factors than to the presence of menhaden. A more credible explanation is the "thermal niche/oxygen squeeze" theory. Currently, large amounts of run-off in the Bay have created areas with low levels of oxygen, called hypoxia, in cold waters that bass traditionally inhabit. Because the waters that they are most suited to are uninhabitable, bass spend more time in warmer, shallower waters. The temperature of these waters are too high for the bass to feed properly, leading to a variety of health problems, including susceptibility to mycobacteriosis.