Duck nesting in fields of undisturbed grass-legume cover

Harold F. Duebbert; J. T. Lokemoen

doi:10.2307/3800154

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Duck nesting in fields of undisturbed grass-legume cover

Harold F. Duebbert·J. T. Lokemoen

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Abstract

A study of dabbling duck ( Anatinae ) nesting was conducted during 1971-73 on nine 12- to 54-ha Cropland Adjustment Program fields in the prairie pothole region of north-central South Dakota. The tall, dense vegetation was comprised of introduced cool-season grasses and legumes, primarily smooth bromegrass ( Bromus inermis ), intermediate wheatgrass ( Agropyron intermedium ), and alfalfa. Complexes of temporary, seasonal, and semipermanent wetlands surrounded the fields at densities of 1.5-8.1 basins/km2 and areas of 9.4-17.2 ha/km2. Of the 620 nests studied, 38 percent were of blue-winged teal ( Anas discors ), 24 percent were of mallards ( A. platyrhynchos ), and 24 percent were of gadwalls ( A. strepera ). Densities of nests of all species averaged 67, 114, and 47 nests/km2 (3-yr av 77/km2). Calculated hatching rates were 69, 58, and 32 percent (av 56) for the 3 years. Hatchability of eggs in successful nests averaged 97.1 percent. Averages of 4.0, 6.2, and 1.2 ducklings were hatched per hectare in 1971, 1972, and 1973, respectively (3-yr av 3.7/ha).

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Journal of Wildlife Management Article

Source-reported bounding extent: 42.479635° to 45.94531° latitude; -104.057698° to -96.436589° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Harold F. Duebbert, J. T. Lokemoen. 1976. Duck nesting in fields of undisturbed grass-legume cover. https://doi.org/10.2307/3800154

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