In Maryland, the Nature Conservancy has set a tentative target of spending $10 million over four years to protect four key Chesapeake watershed tributaries:
* Nanticoke River, on the Eastern Shore, one of the most unsullied tributaries of the Chesapeake. Its watershed supports almost a third of the state's tidal wetlands, with extensive habitat for waterfowl and threatened plants and animals such as the bald eagle, seaside alder and Delmarva fox squirrel. Governor William Donald Schaefer has identified the river as one of the three priorities of the Chesapeake Bay program. The Conservancy has acquired 700 acres in the last 12 months to serve as "core" areas.
* Nassawango Creek, largest tributary of the Pocomoke on the Eastern Shore, it is lined with the finest cypress-gum swamp in the state and hosts several imperiled animal and plant species. Protection will center around the Conservancy's existing 3,300 acre preserve and will include initiatives to encourage sensitive land-use practices.
* Nanjemoy Creek, home to the largest great blue heron rookery on the East Coast north of Florida. Conservation will center on the herons and the endangered dwarf wedge mussel that has enhanced the creek's ecological significance;
* Sideling Hill Creek, a tributary of the Potomac, which rises in southwestern Pennsylvania and flows southward from the Appalachians through the hills of western Maryland.
Along its banks are some of the nation's finest shale barrens, with rare endemic plants and even a rare butterfly. The creek bed itself hosts a globally endangered aquatic wildflower, the Harperella, and a threatened freshwater mussel, the green floater.
Planning for conservation has just begun with a grant from the Abell Foundation.