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| MENHADEN Are they linked to a cleaner Narragansett Bay? by Dan Pedro |
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| All Rhode Island anglers must be
informed of the importance of menhaden in Rhode Island waters, and we need
your help in compiling more information about them. Menhaden are one of the most important links to the ecosystem in Rhode Island waters, both as forage fish for their migratory predators and as our roving filters in Narragansett Bay. 
WATER FILTERS
Let’s first talk about how menhaden serve as roving filters, converting
algae into energy and thus reducing nutrient loads. Atlantic menhaden occupy two distinct types of feeding niches during their lifetime: they are size-selective plankton feeders as larvae, and filter feeders as juveniles and adults. An adult menhaden, through its unique filtering gills, is able to process up to 4 gallons of water per minute or a million gallons of water every 180 days. DO MENHADEN SPAWN IN OUR BAY?
Menhaden migrate north in early spring each year, with the larger
and older fish going farthest north, but with fewer older/larger fish
in the spawning biomass, less and less adult menhaden are reaching our
bay each year. The average adult menhaden that enters Rhode Island water is of the four-year-old class, and capable of filtering 2 million gallons of water a year - and that’s per fish!! Could they help clean up an algae bloom in our
Bay?
Menhaden gather where nutrients in the form of algae are concentrated, such as our upper Narragansett Bay. While in our upper bay, menhaden feeding on phytoplankton and plant detritus (decaying organic matter). They help to clean up our bay through their unique capacity to remove excess nutrients from the water column and rejuvenating our bay In a study done by marine biologist Sara Gottieg at the University of Maryland, she estimated that for Chesapeake Bay, this ecological function of removing excess nutrients is worth up to $90 million per annum, counting only the reduction in nitrogen and not the other nutrients and phosphorous, that algae also contains. What is the worth of this ecological function here in our Bay? There are areas of our upper Narragansett bay that are still closed to shellfishing. The "roving filters" ability of menhaden are needed to continue to clean excess nutrients out of the water column, and woul help to clean those shellfish areas. I feel that ALL areas closed because of pollution should also be closed to harvesting of menhaden for commercial sale, helping to insure improvement to the water quality of those areas . GAME FISH NEED MENHADEN
Let's talk about the other ecological role menhaden play as forage
fish for other migratory species found right here in our Narragansett Bay.
Menhaden are a major food source, for a wide number of important predatory fish species including, but not limited to, striped bass, bluefish, squeteag, fluke, flounder and scup in our Bay, and are also valuable to offshore species such as bluefin tuna, and sharks. Since predators in several ecosystems eat menhaden, they serve as a direct pelagic link in the food web chain between detritus and plankton right up to the top predators. For striped bass alone 60% of there dietary consummation would be menhaden if enough were available to them in our Bay and the Larger Bass of previous years would return and stay in our bay. In recent years both commercial rod and reel fisherman and recreational anglers have been noticing that the larger bass in length do not weight as much as they did in previous years as a result in fewer forage fish available to them. WHAT DO YOU THINK?
There are many studies that prove the value of menhaden to the ecology
of bays and estuaries. The Rhode Island Saltwater Anglers and affiliated
groups have formed a special Menhaden Subcommittee to assemble as much
information as possible and to work to conserve and improve this valuable
resource.We need your help. Do you have information on studies and facts on menhaden? Are there any current or past studies or surveys on menhaden that you have a copy of? Let’s make this
the
“Year of the Menhaden” in Rhode Island! Please help us by sending any information you may
have to:
MENHADEN@RISAA.ORG or mail to: RISAA Menhaden, 6 Arnold Road, Coventry 02816 • Dan Pedro is the delegate to RISAA of the Narragansett Pier Sportfishing Association. |
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