The establishment of dense nesting cover (DNC) for breeding waterfowl is a common management practice on large blocks of former agricultural land. The Delta Waterfowl Foundation's Adopt-A-Pothole (AAP) program establishes DNC adjacent to small wetland complexes to increase waterfowl use and productivity. I evaluated waterfowl use and nesting success on AAP lease sites in southwestern Manitoba in 1993-94.

Diving duck breeding pair densities were higher on treatment sites. Dabbling duck breeding pair densities did not differ between sites. Upland nesting success did not differ between control and treatment sites in 1993 and was higher on control sites in 1994. Overwater nesting success did not differ between treatment and control sites. Overwater nests located in $<$30 cm of water were predated more often than expected.

Deeper water may provide greater security from predators for overwater nesting ducks. Wetlands appear to provide attractive mallard nesting habitat. The establishment of DNC adjacent to small wetland complexes located in agriculturally dominated landscapes may provide relatively secure and attractive waterfowl nesting habitat. However, other factors, including the presence and abundance of potential nest predators, may influence the effectiveness of this practice.