Northern Prairie Wildlife Research Center
Waterfowl habitat can be developed on sites where none existed before, and wetlands presently of low waterfowl value can oftentimes be improved for ducks and geese by relatively simple, inexpensive measures.
Wetland Types 1, 2, 6, 7, and 8 of the inland fresh series, Type 9 of the inland saline group, and Types 15, 16, and 17 of the coastal saline wetlands are the particularly water-deficient types. Collectively, these nine types comprise nearly 45 million of the 52 million acres (86 percent) classified as of low or negligible value to waterfowl. Wetland-improvement measures applied on an extensive scale to these types could pay big dividends in increased waterfowl use.
In relation to wetland types generally, Martin and associates state:
Improvement possibilities have been demonstrated repeatedly in meadows, marshes, and ponds. Many of these wet areas have been made more attractive to waterfowl by means of low-cost construction enabling effective manipulation of water supplies. Swamps and bogs, on the other hand, generally have limited prospect for improvement, mainly because of difficulties in managing their water supplies satisfactorily and because of costs involved if woody growths are removed. The degree to which any particular wetland area can be made more productive for wildlife depends largely on local factors (water supply, terrain, soil, flora, fauna, etc.) which can be appraised best locally. 
Basically, there are two methods of creating or improving waterfowl habitat. The first method involves impoundment of surface water. Holding a fairly constant year-round water level helps establish submerged and emergent aquatic plants useful as duck food (fig. 4). If outlet controls are feasible and if the water supply is dependable, water can be drawn off during the growing season to favor the growth of heavy seed-producing plants, such as smartweed and millet. Reflooding in the fall makes the new food available to waterfowl.
The second type of wetland development is used where it is impossible or impractical to impound water. By means of so-called level ditches, for example, open-water areas are created in sites where the water table is at, or just below, the ground surface. Level ditches (fig. 5) and potholes (fig. 6) are made by dragline or by blasting. Openings thus created often can be successfully planted with desirable waterfowl foods, but usually planting is not required. These two methods of improving wetlands for waterfowl can be applied in both coastal and inland situations.
Temporary inundation of bottom-land timber, especially in the Alluvial Valley section of the Mississippi River, provides a most attractive winter habitat for ducks. Hardwood bottom lands can be artificially flooded by constructing low earth levees to impound large areas of shallow water. Water from streams can be diverted to the areas by temporary dam structures, by diversion ditches, or by pumping. Drains are installed in low places in the levees to allow complete drainage.
Bottom-land flooding has no adverse effects on timber if the water is drained away during the growing season. In fact, in many cases seasonal flooding may be beneficial to hardwood-timber growth and mast production. Such controlled flooding creates ideal waterfowl areas because water can be managed independently of natural flooding, which may not occur at the best time for waterfowl use.
Special mention should be made of the convenient opportunities for creating good-quality wetlands in connection.with new highway construction. Waterlogged lowlands are often preferred places for constructing highways because the land is cheaper and modern road-building equipment is capable of constructing roads under wet-soil conditions. Instead of using open culverts in low places and at stream courses to drain areas that otherwise would be wet, water-control structures can be installed to hold water on one side of the roadway. The wildlife areas thus created add interest and beauty to the highway.
The so-called 1,000-Acre Marsh near Delaware City, Del., is a classic example of what can be done when highway and wildlife interests work together. Here, a State road provided a dike into which a water-control structure was built. Cooperation of the highway department with local landowners made it possible to control water levels and maintain a valuable marsh that is now highly attractive to waterfowl and muskrats. Similar cooperation resulted in a highway pond above Portsmouth, N. H., where a new turnpike was used to cut off and impound a former salt marsh (fig. 7). The control gate in this case includes a small fishway.
Farm and stock ponds, small floodwater-detention reservoirs, cranberry ponds, and water stored for irrigation and domestic use often may double as wildlife habitats with little or no additional expense. Stock-water ponds in the western parts of the Dakotas and in the eastern part of Montana, for example, afford excellent nesting sites for ducks and receive a high degree of use. Partial fencing of ponds to protect the margins and to provide more favorable nesting cover enhances their value as duck producers (fig. 8).
The New York State Conservation Department has teamed up with farmers and Soil Conservation Districts in an extensive program of marsh developments aimed primarily at benefiting waterfowl and muskrats (fig. 9), although the accompanying water-conservation benefits and recreational opportunities contribute greatly to its popularity.
Another example of how wet areas may harmoniously serve two or more purposes is in rice production. In the major rice-producing States of California, Texas, Louisiana, and Arkansas, flooding of rice fields during late fall and winter results in attractive feeding grounds for ducks and geese. It also affords good waterfowl shooting. Such management for waterfowl usually can be accomplished without upsetting good rice-farming practices.
The public wildlife agencies, both State and Federal, are acquiring and improving wetlands about as fast as funds and manpower will permit (fig. 10). However, in the face of constant pressure for the reclamation of wetlands, private citizens all over the country must also lend a hand to help keep waterfowl numbers from declining. Although many examples of wetland-improvement projects by private groups could be cited, many more projects are needed in all parts of the country. This deserves the serious consideration of all enterprising sportsmen's groups and others who are in a position to do something really helpful for the sport of wildfowling.
There are several useful State publications on waterfowl and wetland management. Private individuals or clubs interested in initiating wetland-improvement projects should consult their State fish and game agency for recent information, as well as for engineering and other technical guidance. Engineering assistance from district offices of the U. S. Soil Conservation Service may be available if the wetlands are developed in conjunction with farm plans.
The following publications will also be helpful:
Waterfowl Management on Small Areas, by C. E. Addy and L. G. MacNamara. Wildlife Management Institute, Washington, 1948.
Food of Game Ducks in the United States and Canada, by A. C. Martin and F. M. Uhler. U. S. Fish and and Wildlife Service, Research Report 30, 1951.
Duck Developments, by W. H. Turcotte. Mississippi Game and Fish Magazine, November 1954.
Ducks on Your Pond, by A. C. Martin. Sportsman's Club Bulletin No. 1, Sports Afield (Minneapolis, Minn.), 1946.
Improving Duck Marshes by Weed Control, by A. C. Martin. U. S. Fish and Wildlife Service, Circular 19, 1953.
Waterfowl Habitat Management in the Tennessee Valley, by John H. Steenis. U. S. Fish and Wild- life Service, Special Scientific Report--Wildlife No. 7, 1950.
Making Land Produce Useful Wildlife, by Wallace L. Anderson. U. S. Department of Agriculture, Soil Conservation Service, Farmer's Bulletin 2035, 1951.
"Management of Waterfowl", by R. E. Trippensee. In Wildlife Management, vol. II, chap. 16. McGraw- Hill, 1953.