Since 1990, the Oyster Recovery Partnership (ORP) has worked to restore oyster bars in the Maryland portion of the Chesapeake Bay.  A main function of the Paynter Lab is to monitor success of restored oyster populations in the northern Chesapeake Bay.  We specifically focus on monitoring spat-on-shell plantings that are coordinated by the ORP.  The ORP obtains spat-on-shell from the University of Maryland Center for Environmental Science's Horn Point Laboratory Oyster Hatchery, located in Cambridge, Maryland on the Choptank River. 

 

Here's a look into a typical Paynter Lab
year of oyster restoration!

 

Ground Truthing (GT)

Ground truthing begins in the early spring to determine viable bottom to receive spat-on-shell plantings.  Bottom with high shell exposure and shallow sediment depth are more suitable for planting as spat-settled shells are less likely to sink into mud and suffocate.  Divers use numbered transects to classify and delineate bottom substrates and shell exposure in order to provide a real-time picture of the site’s conditions.

 Poor bottom with no shell and mostly mud.

Poor bottom with no shell and mostly mud.

 Great bottom with lots of shell exposure and no mud.

Great bottom with lots of shell exposure and no mud.


Post Planting Monitoring (PPM)

The Horn Point oyster hatchery grows spat (baby oysters) and settles them on clean recycled oyster shell to be deployed on predetermined locations during the spring and summer.  Hatchery-deployed shells are sampled in the summer and fall by divers. Remaining spat are counted and measured to determine short-term survival. 

 Hatchery shell deployed by Oyster Recovery Partnership with 3 month old spat (baby oysters) settled on it.

Hatchery shell deployed by Oyster Recovery Partnership with 3 month old spat (baby oysters) settled on it.

 Six-month old oysters settled on hatchery deployed shells.

Six-month old oysters settled on hatchery deployed shells.


Three Year Check In

Long-term survival is estimated by divers in the fall and winter by re-visiting sites three years after being planted with spat-on-shell.  All oysters are counted and measured to calculate hatchery survival and natural recruitment (oysters that weren't hatchery planted). 

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Three year old hatchery clumps sampled during the long-term survival check-in.  These oysters are all still connected to their original host oyster shell. New spat on these three year old oysters are considered natural recruitment.