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At least 703 records · Page 39Linked to original sources
USGS1986

Comparison of wetland drainage during and after protection by 20-year easements

We determined drainage rates for wetlands in North and South Dakota with U.S. Fish and Wildlife Service 20-year easements, during (1961-1980) and after (1981-1984) contract protection. Average annual drainage rates were 10 times higher during the four postcontract years than during the 20 contract years on the same tracts of land. Twenty-year easements only delayed wetland drainage, and are of limited value for securing a long-term habitat base.

Prairie Naturalist↗
USGS1986

Nest sites of ducks in grazed mixed-grass prairie in North Dakota

Habitat use and nesting success of seven species of dabbling ducks were evaluated in five vegetative associations within grazed mixed-grass prairie in central North Dakota. During 1976-80, 548 nests were found on 412 ha of grazed prairie for an annual average density of 27 nests/100 ha. Numbers of nests found ranged from 1/100 ha in 1977 (a drought year) to 58/100 ha in 1979 (a very wet year), reflecting the variability that may be expected in a dynamic prairie wetland environment. Nesting success ranged from an average of 23% in the western snowberry (Symphoricarpos occidentalis) association to 34% in the mixed-grass association. Forty-two percent of the mallard (Anas platyrhynchos) nests and 35% of the gadwall (A. strepera) nests were in patches of western snowberry and/or Wood's rose (Rosa woodsii) that made up 2% of the available cover. Numbers of nests of blue-winged teal (A. discors) and northern shoveler (A. clypeata) were highest in cool-season grasses, especially green needlegrass (Stipa viridula) and western wheatgrass (Agropyron smithii). Height/density (HD) of residual cover decreased exponentially with increased grazing pressure. Use of grazed prairie by blue-winged teal was maximized when the HD of residual cover was 0.5 dm or higher, as could be maintained under light grazing. Results of this study indicated that properly grazed mixed-grass prairie can provide adequate nesting habitat for dabbling ducks. We recommend that preservation and sound ecological management be focused on large tracts of mixed-grass prairie with complexes of seasonal and semipermanent wetlands.

North Dakota↗
USGS1986

Western Stump Lake, a major canvasback staging area in eastern North Dakota

Large numbers of waterfowl, especially canvasback (Aythya valisineria), used Western Stump Lake as a staging area during most of October 1985. Selection of the lake as a conditioning site by this species likely is caused by extensive, shallow-water beds of sago pondweed (Potamogeton pectinatus) and lack of human disturbance. A brief limnological and historical account of the lake is provided.

Prairie Naturalist↗
USGS1981

Grazing intensity effects on the breeding avifauna of North Dakota native grasslands

A breeding bird census and plant survey was conducted on 180 samples of lightly, moderately, and heavily grazed and hayed native grasslands in North Dakota in 1974. The ten most important cover plants on each of eight major physiographic landforms in three of the four regions (the Agassiz Lake Plain excluded) overlapped so extensively that only 19 species were involved: 13 grasses or sedges, four forbs, one shrub, and one clubmoss. Bird densities were generally highest in (i) regions and landforms containing numerous natural basin wetlands, (ii) flatter, glaciated landforms containing more fertile soils, and (iii) landforms of greater relief and high habitat heterogeneity. Avian species richness tended to decrease with increased grazing intensity, but total bird density increased due to higher populations of a few species, and hayland that had been mowed and raked during the previous growing season was highly attractive to some species.

Canadian Field-Naturalist↗
USGS1989

Coleoptera species inhabiting prairie wetlands of the Cottonwood Lake Area, Stutsman County, North Dakota

The aquatic Coleoptera of a prairie wetland complex in Stutsman County, North Dakota, were collected from April 1979 to November 1980. Identification of 2594 individuals confirmed 57 species, including seven new records for North Dakota. Two seasonally flooded and two semipermanent wetlands, totaling 7.43 ha, contained 53% of the Dytiscidae, 43% of the Haliplidae, 38% of the Hydrophilidae, and 22% of the Gyrinidae species previously identified from North Dakota. Although 49.1% of the Coleoptera species occurred in both types of wetlands, the occurrence of 29 species varied by wetland class.

Prairie Naturalist↗