Oyster Gardening at Anable Basin with LIC Community Boathouse:
The Oyster Garden we maintain at Anablle Basin is part of the Harbor-wide Billion Oyster Project (BOP), the regional initiative to restore oysters to the NY/NJ Harbor Estuary. To learn more about the project, check out: https://www.billionoysterproject.org/about/
What is Going on with the Oysters? Report on Oyster Garden Monitoring on August 6, 2015 at Anable
On August 6th we did another complete count of our two oyster garden cages. The data at first seemed underwhelming but upon reflection showed some curious anomalies.
The last two months is the peak of oysters’ growing season and is when the summer warmth triggers their spawning. Naturally we expected to see a growth spurt over our measurement from early July. There were two surprises. First, our counts were higher than in early July. We would have expected somewhat fewer due to predators or natural mortality, but the count was actually greater. How much of this could be due to the untrained eyes of us citizen scientists? Does the counts reflect our enthusiasm to measure – or perhaps we just missed some last month or we were just seeing oysters we didn’t see before. The ‘cluster’ nature of our oyster population has always been a challenge to accurate counting and measurement. And as citizen scientists we would expect some variation and even sloppiness.
The other surprise in August was that the average length in both cages did not change, in spite of being the height of the growing season. Here’s the data in a nutshell – Not the trends you would expect!!
We also continued to observe differences in the marine growth on the two cages and in the ‘reef associates’ in the cages.
More interesting was the difference in cage fouling and life within.The cage closest to shore had relatively few sea squirts, seaweed, sponges and other growths. Inside was our pet green crab, now measuring 3.5″. and several smaller ones, and lots of much smaller critters especially various types of shrimp And there were several unidentified fish over 4″ (see pic). A number of oysters were covered with a thickish rubbery looking/feeling growth. What is it ? The clumps of blue mussels we observed in July were still clumped to the rope and cage by their stringy byssal threads.
The Outer Cage in the Current was so loaded with sea squirts that it took two of us to haul it up. There were few shrimp and green crabs, but some mud crabs, worms, and small fish (1.5″ that look like tadpoles – what are they?
The clumps of blue mussels we observed in July were still clumped to the rope and cage by their stringy byssal threads.
So the mystery remains. Why is the count up when we expected it to go down and why is the average length down when we expect it to rise?
One possibility is that the wild oysters larvae spawned (from somewhere) in 2014 settled on the oyster clumps in the oyster garden cages. An oysters, male and female, are broadcast spawners. When some of the eggs are fertilized, they develop into larvae and after some weeks metamorphose into tiny oysters and eventually settle (attach) on a substrate, preferably another larger oyster shell. These ‘spats’ then begin their lives as oysters. The spats remain very small, a mere speck on the larger oyster shells, but over the months become recognizable as small oysters. It seems likely that they had not grown enough to be recognized as oysters by our citizen scientists until our mid-summer monitoring in early August. We are waiting to hear what the marine biologists at the Billion Oyster Project think.
In Sept, we will get new seed oysters for a new cage we recently built, with its traps consisting of the ceramic tiles, oyster shells and mesh. When we pulled this up, it was already thickly covered with heavy sea weed, some sea squirts, lots of spongelike growth (see pic) Lots of little tadpole-like fish jumping around and out of the sea weed.
Why do these two cages have so much fouling? Could they be too deep off the dock (6′)
And the basic questions remain – why didn’t our oysters grow (or did they?), and what is really going on??
Join us in Sept when we monitor our new oysters and continue monitoring last year’s cages. Date to be announced.
Reported by John Bradley
To be involved in or to be kept informed about this and related projects, contact John Bradley at:email@example.com
CWQT: Citizens Water Quality Testing
Several members of the LIC CB are involved with the CWQT (Citizen Water Quality Testing) program run by the Water Trails Association. Throughout the NYC waterways, volunteers take water samples every Thursday AM during boating season and the results are published by Friday so river users can know if the waters are safe for kayaking, swimming, etc. Currently, LICCB members help sample water from Hallett’s Cove, Anable Basin and Newtown Creek.
If you are interested in participating in this project thru LIC CB, contact John Bradley at:firstname.lastname@example.org
or check out the CWQT links below: