Date of this Version
We contrasted nest success for control areas and experimental areas in eastern North Dakota where we employed professionals to trap mammalian nest predators from late March to late July. In 1995, dabbling ducks averaged 53% nest success on four treatment blocks of 4,150 ha each; whereas on four control areas upland nesting ducks averaged 24% success. Diving duck nest success averaged 57% on experimental areas and 29% on control areas. American coot (Fulica americana) nest success also improved on experimental areas, but blackbird nesting and fledging success were not affected by the treatment. In 1994, nest success of upland cresting ducks was 52%, which was a striking contrast with upland nest success of 6% on the control area. In 1994 and 1995, brood counts were much higher on the experimental areas than on the control areas. Track counts revealed lower estimates of predator activity on experimental sites compared to control sites. This study provides the first strong experimental documentation that trapping, without the use of poisons, can effectively reduce nest predation and substantially improve waterfowl recruitment.