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, August 19, 2009
Wow its been a while!!!
Sorry all. Summer is my busy season, and while I have been snapping lots of photos and working on my research, I have not been very religious in my postings. I will try to do a better job from here on out.
So, some good news, I have my second manuscript accepted for publication in Marine Biology. I still need to make some minor revisions, but that was still very exciting. My abstract was accepted as an oral presentation at the upcoming CERF meetings in Portland, Oregon. I am trying to save money for a diving trip to Fiji this January, where while I hope to participate in many fun dives, I also hope to do a research project involving seagrass meadows there.
But onto the current research- we are seeing larger scallop sets this year than all the previous years combined. In 4 spat collection dates, we have already collected over 30,000 seed scallops. That may not seem like many, but its more than the previous 4 years of monitoring combined. This seems to indicate that the multiple spawning sanctuaries we have set up are working, and in past years may have seeded pockets of spawning individuals in other portions of the bay. This is good news for bay scallops and Long Island. However, I must not be to quick to celebrate, as there is a lot that can happen between now and November 2010, when this years scallop set will be old enough to harvest.
This is also good for my actual research, one aspect of which is examining the roles seagrass patch architecture might play in recruitment, growth and survival. While I have been working on the recruitment and growth aspects of this project, but I had not been observing recruitment to my mats. This has changed this year - likely a combination of a slight change to my recruitment collector design and the apparent increase in larvae in the water column - I have collected ~700 scallops on my artificial seagrass units. This was very exciting. In my two collections thus far, there seems to be a natural experiment going on - in three weeks, the collectors went from an average of 124 per square meter to 56 per square meter - a 50% reduction in a 3 week time frame. This is likely due to predation, but I will have a better idea in the next 4 weeks when I have 2 more collections. This was all very exciting to me.
Even more exciting, is that in addition to seeing scallop seeds set on eelgrass, we are also starting to find scallops set on species of macroalgae. This will hopefully start to shift some of the old ideas that only eelgrass is suitable for bay scallops, because we are observing in the Peconics scallops in and on many other potential habitats!
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.