The Decline of Seagrass Meadows 
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 
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 
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.
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Unexpected oil spill impact – increasing fish?
By JohnnyScallops, on November 12th, 2010
A recent ar ticle in the Press-Register of Mobile, AL, has highlighted some work by a group of Dauphin Island Sea Lab researchers. Now, we all know of the many negative consequences of the oil spill, and they have been highlighted on numerous blogs and websites (see some of those here and here). Now I first read about increases in baby fish in Gulf of Mexico estuaries back in September. Researchers had been monitoring juvenile fish abundances for a number of years, and when it came time to conduct those surveys this summer, after the spill, it appeared as though everything was normal. Some species even were more abundant than normal. So it seemed as though GoM fish larvae had dodged a bullet from the oil spill.
Now, just this week, the DISL crew is at it again. Trawl surveys at a series of sites have yielded significant increases in fish abundance post-spill. This doesn’t mean that the oil benefited the fish. Rather, the researchers are suggesting it was the forced closure of some of the richest Gulf fishing grounds that led to these dramatic increases, strong evidence for the dramatic impacts fishing pressure has on the marine environment. And unfortunately, this unexpected result may make it difficult to truly assess the impacts of the Deep Horizon spill for quite some time.
Here’s a quote from Dr. John Valentine, from the article:
“There has been an awful lot of debate about longlining, gill netting, commercial fishing, recreational fishing, about how the ocean has been restructured by man,” Valentine said. “This was the first time we’ve ever seen such a large scale cessation of fishing.”
He said that the fishing closure appears to have demonstrated for the first time “how resilient the ocean really is if widespread management measures are applied.”
However, the GoM is hardly in the clear, and all the researchers involved are quick to point out that this increase isn’t necessarily good news. Many fish and fish larvae were likely lost in the spill, and it will taking longer to discern these effects with the dramatic impact the fishing closure had on the data. Either way, it is an interesting story, and certainly one worth thinking about.
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About me  I am a marine biologist that is currently attending graduate school at the School of Marine and Atmospheric Sciences, Marine Sciences Research Center, of Stony Brook University, New York. I am very interested in marine ecology and have been focusing my studies on bay scallop interactions with their habitats. I plan to investigate various anthropogenic impacts on bay scallop populations for my PhD dissertation. This blog will highlight the details of my graduate research, from bay scallop-eelgrass interactions as previously mentioned, to alternative habitats for scallops, such as Codium, to trophic cascades, and more. Enjoy! Artificial Seagrass Is a useful experimental tool to mimic natural seagrass while controlling many factors, such as density, canopy height, leaf number, which are usually confounding in natural eelgrass meadows.
Scallops seem to love this stuff!
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I have said this to various people as the oil spill was going on and all they did was brush me off. I said, “wouldn’t this be sort of a blessing in disguise since lots of area would be off limits to fishing allowing stocks to make a little bit of a come back due to the lower fishing pressures.” However, I am aware that benthic organisms in these areas are probably not going to see the same results since they are probably buried under sludge. Score one for me.
Crickets, that also comes dangerously close to comments made last year that piracy was good for fish because it made fishermen afraid to leave the harbor. That comments generated a LOT of negative feedback.
Interesting post, Johnny, and welcome aboard.
Sometimes the most controversial things are the ones that make the most sense! haha