EASTON — Scientists at the National Oceanic and Atmospheric Administration are extending the agency’s expertise in mapping and surveying into the restoration and the habitat world.
The survey work being done by NOAA scientists is not just about collecting depth data, said Jay Lazar, a scientist doing survey and mapping work for NOAA. It’s also about collecting habitat and seafloor composition information from acoustic sonar data — what kind of bottom is out there and if it is suitable for oyster restoration.
NOAA will survey tributaries listed in the U.S. Army Corps of Engineers’ master plan and designated as sanctuaries by Maryland Department of Natural Resources.
“That course delineation habitat is the basis, or the starting point for assessing whether or not a tributary has an amount of bottom that can be restored, that should be restored,” Lazar said. “For instance, if this is predominately mud, and the available habitat doesn’t meet the metrics for how much you need, then you move on.”
But, that’s just one part of the survey and mapping work being done by NOAA.
Lazar called Harris Creek the proxy tributary for all other tributaries eyed for restoration work. It was the first tributary set aside by the state in 2010 as an oyster sanctuary.
“We’re getting in (Harris Creek) and it’s meeting all those tests. This vessel then goes in and does, for lack of a better term, it’s a detailed investigation,” Lazar said.
That detailed investigation involves collecting higher resolution data, using tools to look at whether the area is still suitable for oyster restoration, Lazar said.
Information collected through the detailed investigation feeds into a “restorable bottom assessment” and later is formed into a tributary plan, which is then taken through a public comment period, he said.
Then, it’s basically down to implementation, Lazar said. After the initial survey work is done by NOAA and the right bottom is targeted, the Army Corps constructs a base for the oyster reef and substrate is placed on the site.
The Tred Avon River is nearing that point in its oyster restoration lifespan.
According to Sarah Gross, a spokesperson for the Army Corps in the Baltimore district, the reefs in the Tred Avon will be constructed of rock or shell substrates.
"Oyster seed, which are technically referred to as spat on shell, are brought from hatcheries and placed or ‘planted’ on the constructed reefs in hopes of restoring the oyster population in these areas,” Gross wrote. “Once planted, the oyster reefs will be monitored to assess the restoration progress.”
Lazar and Andy McGowan, a field technician with NOAA, were working in Harris Creek in early September doing an “as-built survey,” Lazar said, monitoring restoration progress.
”Much of the complexity that was inherited in natural reefs has been lost to harvest, with effectively strip mining these reefs, which is essentially what dredging is, just strip mining of the structure that’s out there,” Lazar said. “You level it off, you lose that completely, you took that natural variability, that natural patchiness, and that’s ultimately where things like sedimentation eventually come in to play.”
Lazar said nobody has really known the effect of restoration, which is what NOAA is doing through the Oyster Reef Ecosystem Services project..
Questions like whether restoration is working, what its value is, how well it is working and for whom it is working, are what NOAA is working on with regard to Harris Creek, monitoring the reefs constructed there to see if restoration is paying off and to quantify the effects of oyster restoration.
Lazar said NOAA also will use larvae transport models developed by the University of Maryland Center for Environmental Science’s Horn Point Laboratory, which also supplies the oyster spat for plantings, to look at the potential impacts of restoration on a particular site and see how much other areas surrounding the site can be affected.
"This is the first time that we’ve really been able to establish restoration projects on a scale that have the potential to make a real difference,” Lazar said. “So we really want to know, is this idea of restoring the oysters, is it attainable?”