Becky Walawender from the Department of Biology here at ODU has been monitoring the soft shell clams that were recruited into our tank this spring. Here she describes the results so far.

Soft-shell clams (Mya arenia) have fragile, thin shells made of calcium carbonate and are susceptible to breaking under the acidic conditions associated with excessive carbon dioxide. To test this, we placed 110 soft-shell clams into sediment and monitored their survival in five different pH levels (6.0, 6.5, 7.0, 7.5, 8.0). After two months, we noticed a decrease in survivorship of the clams in pH 6.0. Of the remaining 90 clams in the pH 6 tank (20 were removed for genetic analysis), 55 were confirmed dead, mortality in the other treatments was approximately 6-11 clams. The shells of the dead clams from pH 6.O became brittle and eroded through at the middle, below the umbo.

Clams from pH6



After a year and a half of planning, construction and wiring we have finally reached the start point of our long-term seagrass ocean acidification experiment. Last week Dick and I spent two days diving in the seagrass meadow in South Bay on the Eastern shore collecting over 1 thousand seagrass shoots to fill our experimental tanks. The rest of the BORG team spent their days cleaning the tanks and awaiting our seagrass booty.

As the plants need to survive and thrive in our tanks we had to collect not just the shoots, but the rhizomes and roots as well. In the muddy sediment of South Bay this required lots of rooting around, so much so that it looked like I had been eating mudpies when I came to the surface!


It took three days to plant all of the collection, each tray now has approximately 40 shoots and each tank has between 3 and 5 trays of South Bay grass, some tanks have grasses from Washington State for a side experiment on their tolerance to our warm summers. Now we have wait for a couple of weeks to make sure that the growth rates in all the tanks are the same before we can turn on the CO2 and start the different treatments. We have managed to recruit some folks from both Biology and OEAS to run experiments in our tanks, Becky, a graduate student is going to study the clams that were recruited into the tanks during the spring and Dr Dobbs is going to look at bacterial films.

I will post more details on those experiments once they get started. In the meantime we will all be working on our tans this summer as we spend several days each week tending to our seagrass crop.


The flowing seawater system at the aquarium has been providing our tanks with lovely fresh creek water, the only problem is all the algae that comes with it. The algae foul the sides of the tank as well as the seagrass, and combined with all the leaves that have fallen from the surrounding trees this makes for a lot of crud in the tanks. We need to reduce the fouling as much as possible as it will cover the seagrass and prevent light from reaching the leaves. Once we transplant our seagrass in January we will be at the facility several times a week and keeping the tanks clean on a regular basis. Our mission last week was to get the tanks clean and ready to receive seagrass in the new year. We skimmed all the leaves off the surface, then drained each tank and scrubbed the algae off the sides finishing with scooping all the crud off the bottom. We had two trays of seagrass that we placed in a tank last month as a test, they were heavily fouled and we feared that they would be dead, but under all that algae they were alive and growing, so the good news is that seagrass love our tanks.

We also made screens for each tank to prevent leaves falling in and to reduce the light to levels the seagrass would experience in the natural environment. With this done they we are set for transplanting in January.

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It seems somewhat illogical to fly 13 hours on a plane and ride 6 hours on a bus (total trip equaling 27 hours) for a meeting that is only 3.5 days long. However, there was no turning back once we boarded the plane in New York bound for South America. The Coastal Estuarine Research Federation 2012 meeting in Mar del Plata, Argentina was meant to bring the two American continents together, but it also attracted scientists from Europe and Australia – a truly international meeting. It was also a tribute to Scott Nixon, one of the grandfathers to marine ecology, who passed away unexpectedly this year. The small meeting size allowed students and researchers to intermingle over the abundant pastries and drinks provided and tango lessons brought us all dancing together in a small, crowded room. Eating and dancing aside, the CERF 2012 meeting was a huge learning experience for me. With no co-occurring sessions, I was able to listen to a broad range of research topics, from new studies on coastal eutrophication, to the physics of the Plata River, to the fishery rivaries between Chile and Argentina (don’t mess with the Chileans!). More so, I was impressed with the caliber of research presented by the South Americans and their ability to do so much, with much less than most US scientists. My oral presentation was well received, so I now have two meeting presentations under my belt! All in all, it was a great experience and I met several people I plan to stay in touch with throughout my career. I also learned that sometimes it’s worth it to travel 27 hours in the name of science.

Meredith McPherson

Meredith is a masters student with the BORG, she is only a few weeks away from defending her thesis.

Good news! We now have power and flowing water at the experimental seagrass facility, this is a big step for us as it has taken quite a while to get through the construction phase of this project. Our next task was to set up the data and power cabling to each tank. We have spent the past two weeks pulling cables through hundreds of feet of piping to connect each tank to the mobile lab. Today we finished the cabling and the next step is to start setting up the control boxes which will monitor pH and temperature within each tank. It was a beautiful day at the aquarium, we have a very pretty spot right on the creek. Here are some pictures of us working hard.

We are all very excited to be have been awarded a new grant from NSF Office of Polar Programs! The title of our new project is “Warming and irradiance measurements in the Arctic: Determining the link between solar energy absorption and surface warming through long term observations.” This project will look at the connection between seasonal warming of arctic surface waters and the absorption of solar energy. We will be measuring temperature and light both in the ice and the water column at hourly time intervals using a new buoy system, in addition we will add a fluorometer at 5m depth in the water which will help us identify absorbing compounds such as phytoplankton and coloured dissolved organic material. Our collegues in this work areDr’s Mike Steele and Bonnie Light from the Applied Physics Lab at University of Washington, and Pacific Gyre who will make the buoys for us.

As we get to travel back to the Arctic for this project there is a lot of excitement in the lab, everyone wants to see polar bears. I’ll post more information as we progress with this project, we will be making the data from the buoys available in near real time, and will also develop a lesson plan for teachers. For now I will leave you with a picture from our last trip to the Arctic.

This the view every morning as I exit my sleeping tent.