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At least 721 records · Page 40Linked to original sources
USGS1989

Breeding canvasbacks: a test of a habitat model

Schroeder (1984) proposed a habitat suitability model for breeding canvasbacks (Aythya valisineria) based on the size, water regime, and emergent vegetation of wetlands. We evaluated the model with data from surveys of canvasbacks on 2265 wetlands in North Dakota, South Dakota, and Minnesota. The model proved inadequate as a predictor of canvasback pair density; the correlation between values produced by the model and canvasback pair densities was r = 0.0023 (P = 0.911). There were, however, suggestions of (1) higher canvasback density and frequency of occurrence on wetlands with more open interiors, and (2) a relation between canvasback density and wetland size that varied according to wetland permanence. We recommend that the model be improved by testing these relations, and possibly by incorporating determinants of water quality or pondweed (Potamogeton spp.) occurrence.

Prairie Naturalist↗
USGS1981

Observations on black-crowned night heron breeding success in a North Dakota marsh

Storms and mammalian predation severely reduced production in a Black-crowned Night Heron (Nycticorax nycticorax) colony in two years and drought prevented nesting in two other years from 1976 to 1980. Maximum estimated production was 2.2 young per pair in 1978, the only year production was sufficient to maintain the population.

Canadian Field-Naturalist↗
USGS1984

Breeding bird community colonization of sown stands of native grasses in North Dakota

Breeding passerine birds were studied in three native grass plantings of predominantly western wheatgrass (Agropyron smithii) and green needlegrass (Stipa viridula) in south-central North Dakota during 1982-1984. A total of eight different species of passerines readily colonized this relatively new type of wildlife habitat during the second, third. and fourth growing seasons.

Prairie Naturalist↗
USGS2001

Range expansion of pileated woodpecker in North Dakota

Natural history writings from explorers such as M. Lewis, W. Clark, J. J. Audubon, S. F. Baird, and E. Coues failed to mention the pileated woodpecker (Dryocopus pileatus ) in North Dakota throughout the 1800's. The first published reference to the species was in the early 1900's in the valley of the Red River of the North, part of the Agassiz Lake Plain of eastern North Dakota. Sightings increased in the Agassiz Lake Plain in the mid-1900's but remained rare west of the Agassiz Lake Plain until the late 1900's. Ornithologists suggest that the species has recently established small, permanent populations in the Turtle Mountains, Devils Lake area, and along the Sheyenne River, especially in the Sheyenne National Grassland. I present information that supports the idea that the pileated woodpecker is establishing populations in the aforementioned areas and is moving even farther west. I also document the presence of the pileated woodpecker along the James River and the first record for Stutsman County.

Prairie Naturalist↗