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July 2014
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The Decline of Seagrass Meadows

Zostera! Eelgrass, Zostera marina, is a flowering, marine vascular plant that remains submerged all the time. This is quite a feat for vascular flowering plants, and only a few dozen species world wide are capable of growing completely submerged in a marine environment. Eelgrass creates and extremely important habitat, its upright structures and complex root system create a 3-D living space for many different types of animals. It is (or was) the dominant habitat forming SAV (submerged aquatic vegetation) throughout much of the coastal waters in the northeastern United States. Unfortunately, for various reasons, eelgrass meadows have seen drastic declines, and in many locations eelgrass only exists in a mosaic of small patches. This is extremely bad news as many of the important, and formerly important, commercial and recreational fisheries of the northeast US are dependent on Zostera at some part of their life cycle as a nursery and foraging ground. Some of the species are finfish like tautog, bluefish, fluke, winter flounder, porgies, while others are shellfish such as blue mussels, hard clams, oysters, bay scallops, and blue crabs. Many of the aforementioned species support or once supported vibrant fisheries. Many of those fisheries have collapsed, also for various reasons. However, is it possible there is a link between the crash of the fisheries, the decline of Zostera and the failure for recovery on both ends?

Bay Scallop on Eelgrass

Argopecten on Zostera! Bay Scallops, Argopecten irradians , have developed a very close relationship with eelgrass, Zostera marina. As larvae, they are passively transported, and tend to settle in eelgrass meadows when the current is dampened by the 3D structure of the seagrass. This same 3D structure provides post-set juvenile scallops a spatial refuge from predation. Even as larger juveniles and adults, scallops are capable of, and have been shown to, actively select eelgrass habitats.

Other species also use eelgrass

grass shrimp A number of other species utilize eelgrass as a habitat. Included are grass shrimp, like the Palaemonetes pugio, other decapods such as blue crabs, bivalves such as hard clams, gastropods (snails), and numerous fish species, including winter flounder, tautog and cod.

Disapointment? Yep…

Maybe I was expecting a battle royal of sorts.  I mean, I had seen Dr James Ammerman of NY SeaGrant take the government position on the Gulf oil spill, painting a rather rosey picture of whats happening down there.  And I have read Carl Safina’s blog posts, seen him on TED talks and watched him on Colbert talking about the devastation of this ecological disaster.  So you might imagine how excited I was to learn that both men, affiliated with Stony Brook’s School of Marine and Atmospheric Sciences, would be on a panel discussing the oil spill.  I imagined the gloves would be off in a no-holds barred slugfest between a government scientists and a staunch conservationist. 

I was telling everyone to go.  I predicted a lot of yelling.

I was disappointed.  I guess I should say I wasn’t disappointed by the news.  It was encouraging to hear the consensus agreement that it could have been much, much worse.  Despite not knowing the exact impact due to lingering effects for a considerable amount of time, everyone on the panel seemed to agree that the oil dissipated quickly, the scenes of oiled animals occurred in a very small portion of the Gulf, and oil only reached a very very small percentage of the marsh lands.  No shouting.  No fisticuffs between Ammerman and Safina, or any of the other members on the panel for that matter. 

And, while they all stopped short of calling the spill the worst anthropogenic ecological disaster in US history, they did raise some very alarming issues.  Basically, the panelists agreed that of greater concern for the Gulf ecosystem is the increasing dead zone and the loss of salt marshes.  While the oil spill was an acute occurrence that will likely have some lingering effects, both the dead zone and marsh losses are Gulf impacts that are occurring over a long timescale and will continue to have considerable long term effects.  In the question-answer period, Safina pointed out that the Gulf of Mexico has a large amount of natural resilience, as long as the ecological factory is still there – but that factory is the salt marsh, an important habitat which is vital for many species during various portions of their life histories.  It is this reason that the dramatic loss of wetlands should be of much greater concern than any one oil spill.  Without marshes, many species wouldn’t be able to recover. 

And yes, while this might seem a little sympathetic toward the oil companies, the truth if that this is a 20-30 billion dollar industry in the Gulf and as long as people continue to drive and use petroleum products, the industry won’t go anywhere.  We are all contributing to that problem.  This event should have strengthened our resolve for clean energy, but as a NATION, we need to encourage a change in policy.  That just doesn’t seem to be happening.  And while I don’t like to get political on here, with the expected results of the coming election, we will be farther away from a clean energy nation despite the events in the Gulf, and our ever increasing pumping of CO2 into the atmosphere.  This is why its important for everyone to vote, even if you have lost faith in your party or aren’t enthusiastic about any candidates, remaining on the sidelines could have very serious repercussions. 

3 comments to Disapointment? Yep…

  • Al Dove

    Hey John. There's a theme there that I think needs to be shouted from the rooftops. It is that singular events don't destroy ecosystems; its the chronic changes in the long run that do the damage. The conversation you witnessed echoes one about another oil spill in Australia, the Shen Neng event. See here and here. We need to get people to pay much more attention to the chronic and less to the dramatically acute. 3,000 people died on 9/11, but ten times that number die every year in car accidents. Somehow, we haven't declared a war on cars yet (we should, it would help with that whole global warming thing)

  • John Carroll

    I agree 100%. But I think like some of the panelists brought up, how do you convince farmers in Iowa that their fertilizers are impacting the Gulf, a place which is so far from them, they have probably never seen? Unfortunately, especially with the advent of the digital media that allows anyone with an opinion to be a "journalist," the only way to get people to read newspapers and watch TV shows is through sensationalist journalism. So its much easier for them to talk about these dramatic events than the chronic ones, because the dramatic events are tangible. And unfortunately, the only ones making noise about the real issues are on science and environmental blogs that receive little attention and are overlooked as biased, and in select classrooms around the country. How do we get the media to talk about the real problems? That is the ultimate question. How do we get marsh loss on the front page of the NY Times?

    Thanks for checking in, though. I appreciate the comments.

  • [...] originally posted back in October how disappointed I was about a Gulf Oil Spill panel I attended, because it lacked the fireworks I was expecting.  That being said, there was a [...]

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