Oyster Status August 14, 2009.

The story of this dive can be summarized by one word "Silt." Since the May dive we had the spring rains and considerable silt has been deposited on our oysters. Approximately half of the surviving oysters have been silted over. When the boats drifted slightly outside the target drop zone last October it was thought not to be a big problem. Lesson learned. The divers scoped out another nearby site for this Fall's placement that will include specially designed netting that will allow for easier counting and monitoring. This site has a stone/gravel bottom, that should allow easier follow-up. The shell bags that were placed showed no signs of spat settlement. We will check on them again in September.

Oyster Status May 2009.

Over the winter we saw and learned a great deal. Unfortunately, our caged population was not adequately tied off and we lost it to the currents. This made the check-up dive all the more exciting. What the dive team saw was 50% survival. At first, this was felt to be disappointing news until we learned form professional growers that this mortality rate is normal. Samples were taken for measuring growth and the average body (meat) weight increased ~20% and shell length increased 8%. The monitoring approach will be discussed at the NOAA Coastal Zone Meeting in July.

Oyster Status November 8, 2008.

The news from our follow-up dive and check on our caged population is good. We had minimal casualties from the placement and the divers observed active filtration.

We are learning about our harbor.

While we thought we knew a lot at the outset, we are learning a tremendous amount about our harbor, the oysters and their environment.

• The harbor is quite vital with lobster, crabs, starfish and mussels.
• The bottom does have a bit of silt, but it is not mucky.
• The salinity varies dramatically due to the influx of fresh water from the Charles, however, it appears our oysters are deep enough to be largely in salt water.

Our dive team volunteers Mat Brevard and Rich Bradshaw pose with Charlestown resident Pam Brodie.

The presence of divers caused quite a few passersby to stop and watch..

After an agonizing wait- They are alive! with less than 1% mortality.

Oysters and mussel in bag

Blue mussel with oysters in caged population.

Oyster with a tunicate, looks like Botrylloides from caged population.