Zostera marina is a seagrass species, commonly known as eelgrass, that is found on both coasts of the United States, as well as in Europe. Unfortunately, Zostera is disappearing all over the place, including right here in New York. This could have devastating impacts on animals that rely on eelgrass as foraging grounds, or, as is the case with scallops, use it as a refuge from predation. This is its story, as seen through the eyes of an aspiring graduate student...
Wednesday, October 22, 2008
Bubbles, bubbles everywhere, but not a drop to drink...
Adult bay scallop in a Codium fragile bed Well, there were certainly a lot of bubbles yesterday. I went diving, but in addition to the normal exhalent bubbles from every breath, my Air2 was leaking, creating more bubbles and increasing my apparent air intake. But that didn't stop me from doing my transect surveys at 5 sites in the Peconics. We stopped all around Northwest Harbor (East Hampton, NY) and Sag Harbor, and then 1 dive in Southold Bay. While we didn't see as many scallops as we would have liked, we did see a few, which was good. In most places, we saw more seed A seed bay scallop in Codium A bay scallop "smiling" for the camera... Old Blue eyes A seed bay scallop, note the darker mantle than the one above than adults, An adult bay scallop with its epiphytic and epizooic growth which is good and bad. It is good in that hopefully there are enough seed to survive over the winter and spawn next year. It is bad for the commercial and recreational guys that there aren't enough adult scallops (potentially) to go around. Who knows how this year ends up. However, I did see a decent number of scallops, small fish, hermit crabs, spider crabs, mud crabs, grass shrimp, whelks, your usual suspects. A nice day diving, although cold (12.5C). Its about time to break out my drysuit. The visibility and diving this time of the year is the best though, so I won't complain. Going again on Friday. Stay tuned.
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!
Eelgrass is an important habitat for multiple marine species, including the bay scallop
Scallop on Artificial Eelgrass
This tethered juvenile bay scallop attached itself to my artificial eelgrass...
The decline of eelgrass 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?
Eelgrass, Zostera marina, a temperate seagrass species, providing a vital habitat for numerous marine species
Scallops in eelgrass
Some adult bay scallops we planted in eelgrass for a free release survival experiment we conducted
If you live in coastal zones, urge your local and state representatives to push for environmental issues that you are concerned about. Ask for more stringent rules regarding the destruction of existing eelgrass. Encourage restoration programs to be set-up. Call your state and national representatives and ask them what they are doing to protect our precious resources. Practice safer boating and know the undersea terrain - i.e., don't drive your boat in very shallow water. Avoid clamming in eelgrass meadows.