In early 2010, DU received a $75,000 North American Wetlands Conservation Act (NAWCA) grant and partnered with the U.S. Fish and Wildlife Service to test experimental techniques to restore ditched tidal salt marshes on the Parker River National Wildlife Refuge (NWR) in Massachusetts and the Rachel Carson NWR in Maine. Located less than 40 miles apart, these refuges were established to provide important migration and wintering habitat for waterfowl and shorebirds along the north Atlantic coast.

Unfortunately, coastal states from Virginia to Maine have lost up to 74 percent of their historical wetlands. By the 1930s, more than 90 percent of the salt marshes in the northeastern United States had been ditched for mosquito control. Ditching reduces habitat diversity in marshes by eliminating natural ponds and pannes that provide open water for foraging birds. This practice also drains marsh pools and lowers water levels, allowing shrubs and exotic vegetation to replace valuable wetland habitat.

This project will permanently protect 33 acres and restore 14 acres of tidal salt marsh habitat on Parker River NWR and restore another 20 acres of tidal salt marsh on Rachel Carson NWR. Marsh restoration techniques include mowing existing salt marsh, rolling cut grass into log-shaped bundles, and staking the bundles in ditches. The grass structures slow tidal flows, allowing sediment to settle and fill ditches over time. The cut grass also serves as a seed source to help new grass become established once ditches begin to fill with sediment. Protected and restored tidal salt marsh will provide foraging, migration, and wintering habitat for a variety of waterfowl, including black ducks, pintails, mallards, gadwalls, American wigeon, Atlantic brant, and Canada geese.