Predator Management: Success and Failure in the Devils Lake Area
GARY L. HUSCHLE AND DOUGLAS A. LESCHISIN
U.S. Fish and Wildlife Service, Devils Lake Wetland Management District,
Devils Lake, ND 58301
Waterfowl nest densities and hatching success increased an average of 121% and 23%, respectively, from 1985 to 1988, on five natural islands in northeastern North Dakota after a predator removal program was initiated in 1986. Nest densities built up to a high of 41.5 nests per hectare with hatching success of 89.2% in 1988. The rapid buildup of nesting hens over this period may have been the result of increased recruitment due to predator control. However, nest densities and hatching success declined 68 and 54%, respectively, from 1988 to 1989. Lower nest densities and hatching success in 1989, compared with 1986-88, may have reflected concentrated predator populations, difficulty of conducting predator control under low water conditions, or dry conditions in nearby wetland basin complexes during a severe drought.
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