Road to Bay Restoration

by C. Ronald Franks
B
ay grasses (also known as submerged aquatic vegetation or "SAV") are a critical resource that provide food and habitat for a wide range of Bay species, including crabs, fish and waterfowl. Bay grasses also protect shorelines from erosion, remove nutrients from the water, produce oxygen and trap sediments that cloud Bay waters.

Restoring bay grasses to historic levels is recognized to be one of the cornerstones of restoring the Chesapeake Bay.

Unfortunately, underwater bay grass acreage in Maryland's portion of the Chesapeake suffered a setback in 2003, a result of reduced water clarity caused by record levels of rainfall, and the larger than normal runoff of sediments and nutrients that ensues.

While acreage Baywide dropped 30 percent from 2002 to 2003, acreage in the Maryland portion of the Bay dropped from 52,546 acres to 30,990 acres - 41 percent.

Despite the overall reduction in bay grass coverage, several areas recorded their highest levels since the Baywide SAV survey began in 1984, including the Bohemia, middle Patuxent and upper Patuxent Rivers. Additionally, the middle Potomac River continued a two-year recovery. Analyses are under way to understand why grasses in these rivers increased while declining throughout most of the rest of the Bay.

The Maryland Department of Natural Resources (DNR) has long recognized the need for a large-scale restoration approach. There are areas of the Bay where water quality has improved sufficiently to support bay grasses, yet natural revegetation could not take place for lack of seeds. Previously existing methods of collecting grass seeds by hand simply could not provide the number of seeds needed to support our restoration goal - 1,000 acres by 2008.

Today DNR is greatly accelerating the pace of bay grass restoration, using a combination of new technologies and conventional equipment. These restoration activities are being focused on unvegetated areas with suitable habitat, and there is the possibility that planting or seeding large beds could also lead to vigorous natural revegetation in adjoining areas.

A photo of the mechanical harvester

In one recent effort, DNR's Resource Assessment Service used a mechanical harvesting boat as an innovative approach to more efficiently collect large amounts of eelgrass seeds.  These photos document that effort.

Using this new technique, DNR biologists estimate they will harvest 20 million eelgrass seeds this year (compared with 500,000 last year) which could restore 100 acres of eelgrass.

DNR biologist, Mark Lewandowski, helping with the eelgrass harvest.

DNR biologist, Mike Naylor, helping with the eelgrass harvest.

A picture of eelgrass seeds.

This new method uses a boat to "mow" the grass beds, taking seeds and reproductive shoots but leaving the roots and rest of the plants in place.  Only a small portion of the seeds and reproductive shoots are removed from each healthy bed; these will be planted later in unvegetated areas.

After the beds are "mown", the eelgrass shoots and seeds are taken to DNR's Piney Point Aquaculture Facility on the Potomac River and processed to separate seeds from shoots.  This fall they will then be planed in the Potomac and Patuxent Rivers.

Photos by Mark Odell, Governor's Office


Natural Resource Home
DNR Home