Tuesday, November 18, 2008

The Fall season is in full swing…

Although most people assume that our busiest season is summer they couldn’t be further from the truth. We’re out in the boat a lot during the summer given the great weather, but fall is when most of the real important work takes place. Unfortunately, fickle weather patterns including heavy winds from the northwest keep us in the office more than we would like during this time of year. As a result, we have more work to do than days to do it in and we must take advantage of every field day possible. It is not unusual for me to hold off scheduling meetings until I look at the weather forecast for the week.

Although the fall brings us cold air temps the water takes some time to drop. This change is really tied into colder nights that inch the mercury downward day by day. The opposite is true in the spring when the air gets warmer faster than the water. It’s that whole heat capacity thing that I don’t want to get into now…

One big advantage of working in the fall is that the water clarity (vis) really improves. The algae all seem to take a break for the season and do not bloom. This is less than ideal for our filter feeders like shellfish and perfect for those of us who want to see past our noses while diving. This added light is also critical for the grass as we observe a nice little growth spurt in fall as lateral shoots emerge.

During fall we complete our monitoring for the various test planting sites and we summarize the results of our large-scale restoration projects. If the planting has suffered losses over summer we sometimes observe slight increases in shoot density by November or December. It’s not that the shoots get any larger, actually they get smaller, but what we want to see is more of them. For the some projects we may even replant.

Another advantage of the colder temps is that the crabs slow a little and tend to cause less damage to our plots. Unfortunately, most of the damage has already taken place during the summer, but this is helps to protect our new plantings. This is especially true in January, but this frigid water even slows us down!

This year, we don’t have an overly eventful fall. We just have a few projects to complete before January. Planting sites include Caumsett State Park in Long Island Sound (LIS), Great Gull Island (LIS), Jamaica Bay, NYC and several areas along the north fork. I always like to add at least a couple new test plots and we are still figuring out which ones we will use this year.

Soon we will be breaking out our dry suits. For now I can still dive wet…


Monday, November 17, 2008

“Donut” anyone?

On a recent dive at the Terry’s Point restoration site, I was surprised to observe very small “bald spots” at the center of the larger patches indicating that we may be observing the initiation of what I call “donuts”. In this case, there is still a dense covering of rhizomes, but there are few if any shoots in this open area leading me to believe that some process may be limiting shoot recruitment here.

At many natural meadows in high energy areas we observe distinct patterns including rings, crescents or C-shaped formations scattered throughout the bed. In fact, this distinctive signature helps us to distinguish grass from macroalgae beds in aerial photos in the Sound and Gardiners Bay. Despite the fact that these forms are common, it is not really clear how and when they form.

I always assumed that these started off as circular patches that eventually lose their centers. In some cases there may be a breach of the ring leading to the formation of a “C” or similar. However, since we have not observed this, I just don’t know if this is the process.

Continued observations at Terry’s may allow us to follow this progression. Overall, the grass here is flourishing and the early summer plantings that Steve, Kim and Ali did this year, adjacent to the large patches are doing REALLY well, so there is no reason to think that the grass is under stress here. In fact, I couldn’t be happier with the project.

Only time will tell whether this is beginning of a natural meadow-shaping process. All we can do is sit back and let nature take its course. In the mean time we will continue to plant shoots in the adjacent rocky areas to ensure that this meadow expands and flourishes. I wish all of our sites were doing so well!


Tuesday, November 4, 2008

New Skin for the Nursery!

Steve organized a group of us to replace the plastic on the greenhouse. This was long overdue. We were still on our original covering and I think we put the place up in 2001! Hopefully, with the new plastic we can inflate the roof properly and keep a little more heat in this winter. The first time we installed the plastic it was too tight and we haven’t been able to inflate the roof correctly ever since…


Seeding for diversity…

Yesterday Kim and I went out to our eastern Long Island Sound (LIS) restoration sites and overseeded with seeds from several donor meadows. We were fortunate to collect a large number of seeds from Fishers Island and Mulford Pt. this year and it is time we got them out of the nursery. We will be planting some for restoration, some for grow out in the creek behind the lab, but a large number were destined to increase the genetic diversity at our existing restoration sites.

Because we created the meadows at St. Thomas and Terry’s Points with adult shoot transplants the genetic diversity in these new meadows is probably low. We make every effort to collect shoots from various locations to ensure the highest diversity, but given that these stable meadows could be single clones there is no guarantee that what we collect is genetically diverse.

In an effort in increase genetic diversity at these sites we overseed with seeds collected from various donor populations in the Sound. We have found through the years working at these high energy sites that seeds do not recruit very effectively in the absence of adult shoots. Apparently, the seeds need the moderating influence of these shoots to reduce currents and turbulence that might otherwise dislodge or overly bury the seeds. In the presence of adult shoots, however, they do recruit and grow.

The seeding at St. Thomas involved spreading the seeds at the leading edge of each large patch of grass that we encountered. There is a “leading edge” because the current always runs in one direction given the shape of the shoreline. This way, as the seeds migrate down current they will have the greatest opportunity to be trapped by the stems and other bottom irregularities. If we placed them near the center of these areas, there is a greater chance that the seeds might be transported out of the patches and beyond where they could effectively recruit.

The conditions at Terry’s Pt. are different so I simply sprinkled the seeds throughout the large patches. Other seeds were broadcast outside the patches to see if they could recruit under here.

During our planting we broadcast approximately 500,000 seeds between the two sites. Three quarters of these were planted at St. Thomas site and the balance at Terry’s. Only time will tell how manh of these seeds recruit.