^'^Developing new habitats for waterfowl 



Waterfowl biologists at the Center are testino: 

 methods and materials for development of duck 

 nesting and feeding areas on lands that are not in 

 demand for other purposes. Rarely are wetlands 

 preserved for waterfowl or other wildlife values 

 if they can be drained for farming or tilled in 

 for industrial or other uses. More than half of 

 the country's original 127,000,000 acres of wet- 

 lands have already been spoiled or destroyed for 

 waterfowl use, and the destruction continues. 



Biologists have planned their experiments to 

 find ways to create ponds and marshes where 

 waterfowl can nest and feed and to increa.se the 

 productivity of remaining areas. The Center has 

 constructed 20 lakes and ponds in which water 

 levels can be regulated to provide a variety of 

 conditions for studying the growth of waterfowl 

 food plants. Most of these impoundments, 1 to 53 

 acres in size, are in former swamps, gravel pits, or 

 similar waste areas (see map, pp. 12 and 13). 



Even though many of the impoundments are 

 still in early stages of development, the migratory 

 waterfowl population of the Center has increased 

 each year. On approximately 160 acres of these 

 partially developed areas, up to 3,000 migratory 

 waterfowl now find a suitable place to winter 

 where none existed before. In 1959, 66 broods of 

 waterfowl were produced, with a total of 415 

 young. Among the nesters are wood ducks, mal- 

 lards, Canada geese, and black ducks. The liiolo- 

 gists found that after construction of several small 

 islands, where nests were safer from predators, 

 geese were more successful in hatching and rearing 

 their young. Trials are uiulerway to find ways to 

 l^rovide safe nesting structures for wood ducks and 

 mallards. 



AVater drawdown in ponds is a promising tech- 

 nique for increasing waterfowl-food jiroduction. 

 Wiiere feasible, ponds are constructed in pairs or 

 groups so tliat one pond of a pair can be drained 

 in summer and seeded to waterfowl-food plants 

 such as panic grasses, wild millets, or smartweeds. 

 When the crop is ripe in the fall, the pond is 

 flooded again to make the seed available as food to 

 migrating and wintering birds. This pond re- 



Buildins steel-reinforced concrete water-control 

 structure for new waterfowl impoundment. 



mains flooded through the next year while its 

 counterpart is drained and seeded. If the same 

 pond were drained each year, ujidesirable plants 

 would begin to replace food-producing ones. With 

 drawdowns in alternate years, seed production can 

 be maintained year after year without reseeding. 

 The problem of providing food cannot be solved 

 so simply in all water areas. Permanent ponds 

 have their special problems. For example, runoff 

 from fields causes turbidity in ponds with clay-soil 

 bottoms, as does the rooting of carp and bullheads. 

 Clouded water interferes with the penetration of 

 sunlight, necessary for a good growth of water- 

 fowl-food plants. Desirable plants do not grow 

 well in dark-stained waters or in those that are 

 acid or shaded. Biologists are directing their 

 research both toward finding immediate remedies, 

 such as liming, and toward finding the best plants 

 for growing in acid water or in poor light. 



