OB/CSH Protection Committee

Oyster Survey Video

July 21, 2020 – Laurel Hollow, N.Y. Busy morning for us today with Friends of the Bay board president Bill Bleyer helping to survey oysters diving in Laurel Hollow with the Oyster Bay / Cold Spring Harbor Protection Committee and Dr. Aaren Freeman, Associate Professor, Biology Department, Adelphi University.


(video shot during Oyster Survey July 2020)

From Dr. Freeman:

2019 Survey:

During our dive on September 8, 2019 we surveyed 50 square meters of suitable habitat in the sanctuary and found NO live oysters. We also surveyed about 33 square meters of soft mud, which I would presume is poor oyster habitat – there were also no live oysters in the soft mud habitat.

Just after the survey in 2019, about 80,000 live oysters were deposited in the sanctuary from the oyster gardening efforts in Laurel Hollow and Bayville.


(Diver in Laurel Hollow July 2020)

2020 Survey:

Diving on July 21, 2020 we were able to do a few transect surveys in the OB spawner sanctuary. We surveyed about 150 square meters in the sanctuary; about 125 square meters of this was good oyster habitat (i.e. not soft mud). During the dive we observed over 110 live oysters. Importantly, more than 60 of these oysters were in a “reef” that covered 2-3 square meters. As Rob noted,”it looked like someone had poured a few 5-gallon buckets of oysters on that spot, last year.” A few dead oysters (80-100) were observed in the 125 m2 area, but most (90% +/-) in the “reefs” were alive.

“An important aspect of oyster reproduction is that they are in close proximity for fertilization to occur- so as a spawner sanctuary this is ideal.”

Dr. Aaren Freeman

 

Predation

We checked for predation in the dead oysters, very little evidence of predation was found. A single dead oyster shell was found with live oyster drill (Urosalpinx cinema) egg cases inside. No live oyster drills were found in the survey. All other snails observed during the dive were mud snails (Tritia obsoleta), which do not prey on oysters.

Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey.