Pemetic Tank Setup 4/3/14

We had a good day with Carol Null’s 7th grade class today learning about eelgrass and setting up an eelgrass tank. One thing I would like to clarify from my talk: When you are using the pH meter, you only need to calibrate it every day you plan to use it to measure pH. It doesn’t need to be calibrated on days you aren’t using it.

Here are some of the great questions that came up, and some pictures:

1. When looking at maps of eelgrass in Frenchman Bay in 1996 and 2008, a student asked why the patch of eelgrass in the middle of the upper bay, to the northwest of Hadley Point was still there in 2008 when so much of the eelgrass in the rest of the upper bay disappeared?

This is a question we are always working on. What is it that made the eelgrass disappear in some areas and not others? Some of the possible causes that have been suggested are: temperature, green crabs, dragging, pollution, genetic differences or salinity changes, to name a few. In the mapping done by the Department of Marine Resources of all the eelgrass in the state of Maine in 1996 and 2008, a pattern seems to be that between the two mapping periods, eelgrass was lost in upper bays and estuaries, and gained area in outer bays (closer to the open ocean) and around islands. Perhaps the same thing that caused that trend is the reason that bed survived. Another thing to consider is that the bed that survived is a very deep one.

2. How many organisms are in the tank? Does that depend on what organisms are in the tank?

Start counting organisms and recording what kind you see. Compare with other schools!

3. Does temperature affect eelgrass growth? How does our eelgrass growth compare with other schools’ eelgrass growth, if they have different temperature tanks?

If every school with a tank can measure temperature and leaf length over the duration of their tank project, and enter that information into the database, we can answer that question!

Another student was talking to me about how he was trying to decide if he wants to study marine biology or robotics in college. Anyone who’s wondering this kind of thing can try out some marine biology and see how you like it by participating in the Student Marine Science Symposium on June 5, 2014, the Young Environmental Leaders Program in the summer, and volunteering at our lab! Contact Anna about volunteer opportunities at afarrell (at)

-Jordan Bailey

Pictures (by Anna):











Healthy Mud

Conners Emerson 4/22 7th Grade Class B



When our class was out observing the eelgrass tank, a question popped into my mind. Can the mud effect the growth and/or heath of the eelgrass? And what sorts of things can we alter in the tank to make the mud healthier, therefor making the eelgrass healthier?