Douglas Johnson (Former Employee)

North Dakota is a major fall staging area for the Midcontinent Population of sandhill cranes (Grus canadensis), which is composed of three subspecies: the greater (G. c. tabida), Canadian (G. c. rowani), and lesser (G. c. canadensis). The number of cranes killed by hunters in North Dakota averaged 6,793 during 1990-94 seasons, ranking second highest among crane-hunting states. The...

Review of: Metapopulations and Wildlife Conservation. Dale R. McCullough, editor. 1996. Island Press. Washington, DC. 429 pages. $55.00 (cloth), $28.00 (paper).

We compared breeding bird populations in North Dakota using surveys conducted in 1967 and 1992-93. In decreasing order, the five most frequently occurring species were Horned Lark (Eremophila alpestris), Brown-headed Cowbird (Molothrus ater), Western Meadowlark (Sturnella neglecta), Red-winged Blackbird (Agelaius phoeniceus), and Eastern Kingbird (Tyrannus tyrannus). The five most...

No abstract available.

Increased predation on nests of ducks in prairie uplands, as a result of habitat alteration, has been hypothesized to cause decreased nest success and population sizes. We tested whether, and by how much, nest success declined using data compiled from 37 studies conducted between 1935 and 1992 at 67 sites in the Prairie Pothole Region of Canada and the United States. Nest success...

Duckling survival, an important factor affecting annual recruitment, has not been determined adequately for canvasbacks (Aythya valisineria). We investigated the magnitude, timing, and causes of mortality of canvasback ducklings from hatch to fledging at the Agassiz National Wildlife Refuge (NWR) in northwestern Minnesota during 1987-90. During the 4 years, 217 day-old ducklings were...