Shellfish in the Eelgrass

Bay Scallop in a natural eelgrass meadow off Shelter Island, NY

 Yesterday we had hoped to get out to several of our Long Island Sound test planting locations to check on their status, but unfortunately the heavy fog prevented us from getting that far.  Lucky for us, the fog wasn't really  hanging around the Peconic Estuary as much so we decided to cut our losses and drop in on a few sites that I had been meaning to dive for a while.  These sites included two recently discovered natural meadows that we located using aerial photos this past winter as well as two potential test planting sites.  While the test planting sites didn't look promising, the natural meadows were beautiful and, as usual, we observed some pretty interesting things. 

Four large hard clams growing within a same natural eelgrass meadow off Shelter Island, NY

One observation had to do with crab damage/bioturbation of isolated shoots, but I won't get into that in this post.  The other observation related to the large number of shellfish found in these meadows.  The first photo shows one of the dozens of scallops observed.  This photo was taken near the deepwater edge of the grass where it was more patchy and the scallops really stood out.  I did see losts of smaller bugs, but these were within the dense grass and much harder to find and phtotograph.  The photo immediately above shows some of the  hard clams also observed in the same meadow.  I don't think I have ever seen so many in one location and I know that I have never seen four clustered together like that.

Two hard clams growing within 8" of the group of four shown above

In addition to those four, I found a group of two only 8" away from the first group. The only other location where we have seen a similar density of hard clams was in the meadow on the east side of the ferry terminal at North Haven.  The grass there has since been lost and the clams are gone now but it was another clam hot spot. It just goes to show that as we lose or eelgrass we also lose the fisheries associated with it.  Let's hope this meadow off Shelter Island persists; at this point it looks great.


ChrisP

Amazing Seedling Recruitment in a Natural Meadow

While it is not uncommon to observe the random eelgrass seedling or two in or adjacent to openings in the meadows during winter and early spring, it is a rare occasion when we find large numbers of these small shoots blanketing the bottom.  While diving near Stonington Pt., CT last week, we observed one of these rare events.  I had wanted to drop into this site to observe the natural meadow and compare the growth there to what we had observed earlier in the day at our Little Narragansett Bay, CT. test plots.  However, what I wasn't prepared to find were the incredible number of seedlings.

As I swam through the meadow I saw several large open areas; we usually call these areas "blowouts", but there was no indication as to how these formed as I don't think this site sees heavy wave energy and waves that could scour bottom.  When I dropped into the first open patch I was amazed when I saw all the seedlings carpeting the bottom.  They were all roughly the same size and seemed to be grouped in waves corresponding, more or less to bands of small gravel amongst the otherwise sandy bottom.

In my nearly 20 years of diving in eelgrass I have never seen so many seedlings in one area except for possibly several years ago when a meadow in at Noyack Creek in the Peconic Estuary recruited from seed after loss all of the adult shoots the previous year (these seedlings all eventually died that summer and the meadow was lost). 

In addition to the open patches there were also a number of seedlings growing in and amongst the adult shoots near the edge of the openings (see above).  I did not spend time looking further in the vegetated areas to see what the extent was, but I think the seedlings were mostly limited to the openings and near the edge of the openings.

It will be interesting to visit the same meadow later this year to see if the seedlings survive.  There are any number of reasons why the seedlings can be lost here not the least of which could be overcrowding and competition for space and light.  Other factors could be bioturbation and other disturbance.  

The main question I have is why the seedlings recruited here so well in the first place?

ChrisP

Testing out the new GoPro Cameras

This year we purchased two GoPro submersible cameras to help us with our monitoring efforts.  We have used video cameras before, but not recently since they have always been cumbersome to handle.  The advantage of these new cameras is they are very small and we can mount them on divers, boats or whatever "platform" we want to film from.  So far we have only tried the head mount system to track our monitoring and planting dives.  We hope to use the same system to map restored meadows and I would also like to  record one of our larger restoration plantings from a fixed vantage point, if the visibility is adequate.  The visibility issue seems to be the limiting factor here as the cameras do not work as well in low light and obviously can't see through cloudy water.  Expect to see more of our videos appearing as we learn how to better use this tool. 

ChrisP

Little Narragansett Bay (CT) Test Planting Update

Last week we visited our test plots in Little Narragansett Bay (the CT side near sandy Point) to see how our plantings, that were part of our National Fish and Wildlife Foundation, Sound Futures Fund project, had overwintered.  Our project partner at UCONN, Dr. Jamie Vaudrey had been out on the site the week prior and reported finding plants at our GPS coordinates while searching with an underwater video camera, but we definitely needed to get in the water to see things first hand.  

The plants that we used to establish these test plots were produced as part of one of our volunteer "Marine Meadows" events that was hosted by Save the Sound and Mystic Seaport last year.  Save the Sound have been great partners in organizing these land-based volunteer events within CT to support our eelgrass restoration efforts in LIS.  As you can see from the picture above and the one below, things are looking very good here so far for our LNB test plots.  

 

One interesting thing we observed while diving the site was the deep brown color of the water.  We had seen this somewhat last year, but nothing like the dark brown color we witnessed on this day.  Apparently the recent rains have flushed all the lignins and tannins into the Bay from Pawcatuck river.  We had a pretty good idea of what we were in for as we motored through the channel as our propwash was a rust brown color.  Note that I had to color correct the pictures a little to take some of the brown out as the original photos were even browner than what I observed while in the water.

As we usually do, I was hoping to do some counts to calculate percent survival for each plot, but it was a little hard to distinguish individual plots since the plants had spread from their original locations and a couple areas were missing, probably from Horse Shoe Crab feeding activity that was obvious in area.  There was even a HSC almost entirely buried next to one of the plots.  I think we were actually lucky that the HSC's hadn't dug up even more of the area...

Despite my inability to get any hard numbers on this dive, overall, the plants looked excellent...a little taller than I was expecting, but great.  I was surprised to see that some of the larger shoots approached a meter in length.  I also noticed a number of laterals growing from the base of the plants  which is a very good sign for the coming months.  Another interesting thing about these plants is that they were entirely free of epiphytes.  We usually don't see this.

In order to see how our plants compared to natural plants in the area, since we don't have much experience in CT waters, we decided to drop in on a meadow to the east side of  Stonington Point, CT, where we had observed grass last year.   Here we found very similar if not identical looking shoots(see below) except for the fact that the density was much higher which is to be expected.  Another difference was the fact that the water was not quite as brown as in LNB.

You can also see that the macroalgae gathering near the base of the shoots appears to be nearly identical to what we observed in LNB as well.  Again a good sign indicating that things are a normal looking as they can be for this time of year.

 

We should be back up to LNB at least a couple more times this summer to track the progress of the plantings and we hope that everything makes it through July and August when established plantings can fail due to heat stress and other factors.  Hopefully, this won't be the case here.  If we do get good summer survival, we will definitely be looking to expand on this site to create a large meadow.

ChrisP

Great Gull Island (LIS) Spring Monitoring

Last week we continued spring monitoring at our large-scale restoration sites in Long Island Sound and the Peconic Estuary.  On one trip across the Sound Steve and I checked on Little Narragansett Bay, CT test plantnigs (to be reported on later) and, on the way back, stopped by Great Gull Island (north), NY.  We had only been to GGI once  or maybe twice last year and things were looking good, but you never know when the site is as exposed as this one is.  This site was planted a couple years ago as part of one of our National Fish and Wildlife Foundation, Sound Futures Fund projects.  See photos from two years ago here.

 I was hoping this site had progressed like our plantings on the south side of the island and after seeing everything here, I was not disappointed.  One change this year was a noticeable increase in the number of flowers visible (although not many are seen in the photos I chose to post).  There were a few flowers last year, but the numbers were definitely up this year.  This is a good sign although I don't expect the site to recruit many seedlings any time soon since the energy is so high here that seeds will be either buried too deeply or exported offsite until the patch size increases significantly.

 As far a follow up monitoring, we shouldn't  really have to go back here much this year to check on things, but we may schedule a mid to late summer visit to make sure everything is OK.  I have not decided whether to add more plants here, but it is definitely not on the top of my list at the moment given the other plantings we need to do.  Now it is just a matter of having a little patience and waiting for the grass to expand over time as it spreads vegetatively across the bottom.  The older plantings on the south side of the island clearly show that it is just a matter of creating stable patches to initiate a successful restoration project when the proper site is selected.

That's all for this site for now as I need to report on the other sites we've visited so far this year.


ChrisP