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Providing evidence to improve practice

Individual study: Predator control increases waterfowl nesting success and productivity at two prairie and forest sites in Minnesota, USA

Published source details

Balser D.S., Dill H.H. & Nelson H.K. (1968) Effect of predator reduction on waterfowl nesting success. The Journal of Wildlife Management, 32, 669-682


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Control predators not on islands for wildfowl Bird Conservation

A controlled study at two prairie and forest sites in Minnesota, USA, between 1959 and 1964 (Balser et a. 1968) found that using predator control significantly increased the survival of duck nests (59% of 247 nests vs. 29% of 112) and the number of ducklings produced (from 4,858 to 7,571) compared to the same sites when control was not used. The ‘survival’ of artificial wildfowl nests also increased (81% of 654 nests vs. 34% of 699). The duck species were blue-winged teal Anas discors, mallard A. platyrhynchos, and gadwall A. strepera. Raccoons Procyon lotor, striped skunks Mephitis mephitis and red fox Vulpes vulpes were removed using strychnine-treated eggs and trapping. The authors note that the two sites may not have been far enough apart to prevent predator immigration from control areas to treatment areas, so results may be conservative.