INTRODUCTION

In May of 1986, the United States, Canada and later Mexico signed an international agreement known as the North American Waterfowl Management Plan (NAWMP). The goals of this plan included the formation of partnerships between federal, state and private resource agencies and individuals to fund the acquisition and enhancement of waterfowl and other wetland wildlife habitats in order to stabilize declines, increase populations, and maintain biologically diverse ecosystems to provide benefits and a quality future for people.

By June 1990, the Delaware Division of Fish and Wildlife had prepared its first focus area project plan as a component of the Atlantic Coast Joint Venture of the NAWMP. This plan was designated as the Milford Neck Project and included an estimated 13,500 acres of wetlands and upland buffer habitats. Its eastern boundary extends along six miles of the Delaware shore front which is characterized by a low dune line separating a silty-sand beach from extensive tidal wetlands. The proposed project area is bound to the north by the Murderkill River and extends southward to just below the Mispillion River. The western boundary extends westward to include all tidal wetlands and about 2,200 acres of upland forests and agricultural lands. Included in this area are lands which had been acquired prior to 1980 by the Division and Delaware Wildlands, a private, non-profit conservation organization (approximately 2,300 and 1,871 acres respectively).

The Division of Fish and Wildlife proceeded to develop partnerships with other Divisions, The Nature Conservancy, Delaware Wildlands, Ducks Unlimited, U.S. Fish and Wildlife Service, U.S. Soil Conservation Service and various public and private groups and individual landowners. The first acquisition proposal for 2,300 acres of land in the project area was developed and submitted for funding under the North American Wetlands Conservation Act (NAWCA) in March 1992. Because of a flexibility in funding not available to government agencies, The Nature Conservancy (TNC) was the lead agency in the acquisition and was designated as owner and manager in perpetuity. The total cost was $1,990,000 of which $800,000 was provided under the NAWMP. In 1993, Delaware Wildlands added approximately 950 acres to their holdings through private funding. Late in 1993, a second acquisition proposal for 2,500 acres was submitted for funding under the NAWCA. This proposal was also approved and about $900,000 was provided by NAWCA with substantial contributions being added by other major partners including TNC, Division of Fish and Wildlife and Delaware Wildlands. The total cost was approximately 2.5 million dollars. In Delaware, the NAWCA has provided over two million dollars in the last five years to acquire and protect about 5,000 acres of important wetlands and upland buffer habitat. This figure, when added to habitat owned prior to the NAWMP and additions acquired by the Division of Fish and Wildlife and Delaware Wildlands since the plan was signed, composes over 10,000 acres of the original 13,500 acres in the Milford Neck Project. Much of the remaining land is owned and managed by private conservationists and is protected from loss and degradation in the near future.

CURRENT STATUS AND ACTIVITIES ON THE MILFORD NECK FOCUS AREA.

Since the recent acquisition by the Division of the tidal wetlands north of the Mispillion River, the Division's Mosquito Control Section has been busy implementing their management objectives for saltmarsh mosquito control and wetland rehabilitation.

Like most of the tidal marshes in the mid-Atlantic region, the marsh surrounding a large (approx. 140 acres) upland hummock, known as Rawley Island, had been severely grid-ditched by the Civilian Conservation Corps in the 1930's for mosquito control. The effect of drainage coupled with the mounding of excavated spoil resulted in drastic vegetation changes and loss of shallow, sheetwater habitat. Also, many salt marsh ponds (up to an acre in size) were drained by the indiscriminate ditching pattern. These ponds were once valuable habitat for migratory waterfowl (especially black ducks) and other waterbirds. Some areas on Rawley Island were diked and farmed for salt hay or grazed by cattle for many years. This practice, however, has been abandoned for several decades. Due to the high level of mosquito production in the old salt hay impoundments and the open marsh, the Mosquito Control Section has sprayed as many as 800 acres of the area with chemical insecticides up to 6 times per year.

The Mosquito Control Section has received regulatory approval to perform shallow ponding and ditching using Open Marsh Water Management (OMWM) for control of saltmarsh mosquitoes in this area. OMWM is a source reduction technique which involves the selective excavation of shallow ponds and ditch networks only in mosquito-breeding areas. Mosquito control is realized in two ways: first, OMWM alters the mosquito-breeding sites making them unsuitable for egg laying and conditioning. Secondly, it provides habitat for abundant saltmarsh killifish which eat any mosquito larvae that are produced.

Excavations are done using an amphibious rotary excavator and other low-ground pressure conventional equipment (e.g., backhoe, crane, front-end bucket loader). Excavated spoils are spread thinly on the marsh surface to promote revegetation by existing marsh grasses or used to plug old grid-ditches to restore hydrology to drained areas. Delaware has been using OMWM since 1979 as part of its integrated mosquito control program with much success. OMWM not only provides long-term biological control of mosquitoes which drastically reduces the need to spray insecticides, but wetland wildlife habitat can be enhanced or restored.

Permit conditions stress that only the minimal amount of excavation necessary to control mosquitoes be performed. OMWM ponds are therefore usually less than 0.10 acre in size. However studies have shown that larger ponds (0.25-1.0 acre) are better utilized by waterbirds (Erwin et al. 1991, Whitman 1995). Therefore, at the recommendation of the USFWS, the Mosquito Control Section was authorized to create larger, shallow ponds and plug tidal grid-ditches to restore drained ponds for waterbird habitat.

From July, 1995 to November, 1996, approximately 200 acres of OMWM have been done around Rawley Island. This includes over 14 acres of newly created or restored ponds which are receiving a great deal of wildlife use already. Also, a 17-acre salt hay impoundment was breached in several areas to allow more frequent tidal inundations. This is similar to work done in New Jersey for the restoration of salt hay impoundments (Ferrigno et al. 1987). It is anticipated that there will be some vegetation reversion to Spartina alterniflora with enhanced fish access to provide more consistent biological mosquito control. Furthermore, due to its site-specific nature, performing only 200 acres of OMWM has resulted in eliminating over 400 acres of aerial insecticide spraying. This effort not only provides an ecological benefit, but a substantial long-term economic savings as well.

To promote the partnership aspect of this wetland rehabilitation project, the U.S. Fish and Wildlife Service, The Nature Conservancy (through the Service's "Partner's for Wildlife" program) and Ducks Unlimited have provided matching grants to help fund this endeavor. Similar funds are being sought for 1997. Although they have no expendable funds for this project, TNC has signed an agreement to allow pond restoration (no source reduction) on a 100-acre tract adjacent to DFW property.

In addition to gaining acceptance and recognition through partnerships, it is recommended to promote your project through media events, press releases, educational site visits and the like. Many wetland rehabilitation projects are done in remote locations where projects may proceed relatively unnoticed. Conversely, projects on smaller marshes may be surrounded by houses and area residents may react very negatively and may even delay or halt your project if they are not kept abreast of your objectives. Other funding sources may also become available to you if individuals and agencies are aware of what you are trying to do. A well-informed public can be a valuable asset, therefore, it is well worth the time to promote your wetland rehabilitation project.

Within the next year, the Mosquito Control Section will continue with OMWM at the Rawley Island site and will also be looking to do similar OMWM and pond restoration work on other properties to help enhance the Focus Area for wildlife habitat while reducing the need to apply chemical insecticides. Also, the Division of Fish and Wildlife, The Nature Conservancy and Delaware Wildlands (the three largest landowners in the Focus Area) will be working together to develop compatible Best Management Practices to implement on their respective areas to holistically manage the Milford Neck Focus Area and help achieve the goals of the NAWMP.

LITERATURE CITED

Erwin, R. M., D. K. Dawson, D. B. Stotts, L. S. McAllister and P. H. Geissler, 1991. Open marsh water management in the mid- Atlantic region: aerial surveys of waterbird use. Wetlands. 11:209-228.

Ferrigno, F., J. K. Shisler, J. Hansen and P. Slavin. 1987. Tidal restoration of salt hay impoundments, pp. 284-297. In: W. R. Whitman and W. H. Meredith (eds.). Waterfowl and Wetlands Symposium: Proceedings of a Symposium on Waterfowl and Wetlands Managment in the Coastal Zone of the Atlantic Flyway. Delaware Coastal Management Program, Delaware Dept. Natural Resources and Environmental Control, Dover, DE.

Whitman, W. R. 1995. Modification of open marsh water management for wildlife habitat enhancement in Delaware. In: W. R. Whitman, et al., (eds.) Waterfowl

habitat restoration, enhancement and management in the Atlantic Flyway, Third ed. Environmental Manage. Comm., Atlantic Flyway Council Technical Section, and Delaware Div. Fish and Wildl., P.O. Box 1401, Dover, DE. pp.E-42 to E-64.

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