Maine Nature News

Posts Tagged ‘rock weed’

By Fred Gralenski

Many of us in the Quoddy region were drawn to the coast like characters from a Melville novel, for some reason to be here at a boundary to the unknown, dictated by salt, versus the other different ecosystems of, say, Michigan or New Mexico.  Here we have a definite line of separation between land based critters and plants that generally don’t mix with the marine based critters and plants only a few feet away. But even if one is not a naturalist there seems to be a noticeable difference about the coast. Some say that part of the attraction is the scent of the tangy salt air. But salt doesn’t have any smell.  The smell of the tangy salt air is due to decaying marine organisms.  Are we attracted to the coast by the aroma of rotten seaweed?

The commonest seaweed that we have here is rockweed, Ascophyllum nodosum. There are many thousands of tons of the stuff growing in the intertidal zone in the Cobscook and Passamaquoddy  Bays, and the harvesting of a few thousand tons has triggered a vigorous debate over the practice, monitoring, licensing, method, surcharges and overall long term and short term effects.  It seems it should be simple, but a meeting in Orono and many reports and documents indicate otherwise.  Rockweed is a key species in the ecology of the bays.  Without rockweed just about all of the marine critters would be sorely depleted or eliminated, and clammers, wrinklers, and a host of others that make their living from the coastal waters would see their livelihood disappear.  It is of the utmost importance that the rockweed remain healthy.  A recent article in the Bangor Daily News by two well respected scientists, Robert L. Vadas and Brian Beal, (See Rockweed harvesting: a recipe for sustainability, BDN Feb 18, 2010) advocated for a rigorous enforcement of a harvesting method that leaves the seaweed undisturbed for at least 16 inches above the holdfast.  This, the authors claim, “…would seem to meet the precautionary principle for sustainability and for providing habitat for associated species.”   Pretty tricky considering the terrain where rockweed grows, but maybe something can be worked out.  I would also like to see a peer reviewed study of the nutrient cycle and budget.  I want to know where does all of the nutrient value of the rockweed that is naturally ‘lost’ now go? If a few thousand tons of rockweed are harvested from the bays, which species, if any, get shortchanged?  The bays in the Quoddy region have high nutrient and oxygen levels and the high tides cycle twice daily to maintain a very productive ecosystem.  Strangely enough, a comprehensive study indicated that the nutrients seem to follow the salinity, that is, the majority of the nutrients of Cobscook bay come from the Gulf of Maine.  Does that mean that we in Cobscook bay do not have to be especially concerned about the nutrient value of the seaweed harvest, as the nutrients are just going to be flushed out to the Gulf of Maine?  I don’t know.  If the nutrients are ‘just flushed out’ do they just drop to the seabed of the Gulf or do they remain suspended for a considerable amount of time?  If they remain suspended are they utilized by the inshore phytoplankton, which in turn are utilized by the zooplankton, which in turn are consumed by herring, which in turn are…Oh Oh.  Herring stocks are down.  Since 2004 the allowable catch of Atlantic herring has been reduced by half.  The front page of the same BDN with the article mentioned above indicates the closing of the last remaining sardine cannery in the United States, in Prospect Harbor, Maine.

I inserted a lot of conjecture in between the hard facts.  There are many ways to connect the dots.  But I collected some washed up seaweed this morning.  I wet down my 1’ by 3’ seed starting box, lined it with old newspaper and wet that down, then put down a 1 inch layer of seaweed.  On top of that I put 2 inches of ProMix, and then I put it by the water storage tank of my wood boiler.  After a day of settling and warming up I will plant my onion seeds.  Spring is coming.