Poplar Island Restoration Project

court stevenson and jeff cornwall on poplar islandIn the early 1990s, an effort was initiated by the Port of Baltimore, the Army Corps of Engineers and the Maryland Environmental Service to use material dredged from shipping channels of the upper Bay to rebuild Poplar Island near Talbot County, MD. At four miles long, the restored 1140 acre site approximates the 1847 outline of Poplar Island, which was renowned for its waterfowl, terrapins, fish and crabs. Construction began in 1998 and is expected to continue until 2020. When complete, the island will be equally divided between tidal marsh and upland, and will provide habitat for a variety of migratory and resident wildlife.

Early attempts to establish marsh vegetation using seed were not successful, but in 2003 plant “plugs” put in by hand combined with favorable weather conditions resulted in a robust and natural looking wetland. Horn Point Laboratory scientists have been monitoring the development of the wetland to gain information which will be helpful in future plantings.

Water quality and sediment data (below) recorded in 2004 in the restored Poplar Island marsh and a natural marsh at Horn Point indicate that the restored marsh is also functioning like a natural marsh, although significant differences in sediment chemistry remain.

Conclusions:


● Consolidated dredge material can support much
higher growth than sand (even when fertilized).

● Thus far, sediments are low in sulfides (<50μM), pH
is circum-neutral, NH4 is high (>1mM) and PO4 is low
(<5μM).

● In most respects the new marsh appears to be at
least as healthy as nearby natural Spartina alterniflora marshes.

● Although establishment of vegetation by seeding would be cheaper, transplanting plugs appears to be more successful under the conditions at Poplar Island.

Principle Investigators

Court Stevenson, Jeff Cornwell