Ducks Unlimited joined with US Fish and Wildlife Service, National Park Service, Suffolk County Vector Control and NYS Department of Environmental Conservation to restore approximately 165 acres of salt marsh at the William Floyd Estate in 2000. The Estate, located on Moriches Bay in the Town of Brookhaven on Long Island, is owned by the National Park Service and managed as part of Fire Island National Seashore. The property includes over 600 acres of uplands, submerged lands, islands, and marshlands. Like most of Long Island’s tidal marshes, the Estate’s salt marshes were grid-ditched in the 1930’s in an attempt to control for mosquitoes. The ditches drained the marshes, which in turn severely impacted the natural hydrology of the system, limited habitat availability for numerous species of waterbirds, and allowed for the invasion of non-native plant species such as common reed.
The restoration project focused on installing over 100 ditch plugs on the Estate’s salt marshes. To provide the sensitivity necessary for working in this habitat, an amphibious excavator was used to build the plugs. The plugs were constructed by inserting plywood into a ditch, then backfilling the area landward of the plywood with bog material. The area from which the backfilling material was excavated was created into a fish reservoir, thereby providing deeper water habitat for fish survival during otherwise dry periods. Native salt marsh vegetation ( Spartina spp.) was established on top of the newly constructed plugs to provide stability and reinforcement.
Numerous positive impacts have been observed on the William Floyd Estate salt marshes since the project was completed. Shallow panne habitats have formed on the marsh, providing ideal habitat for foraging shorebirds and other species such as black ducks, rails, herons, and egrets. Fish reservoirs have provided habitat for several finfish species, such as sheepshead minnow and killifish, which are known to provide natural control of mosquito populations. Increased salinity levels have prevented the expansion of patches of common reed. Park Service employees have also observed substantially fewer mosquitoes on the marsh than before the area was restored.