Publications

No abstract available.

Habitat use and survival by nine mallard (Anas platyrhynchos) broods from nests on the James River floodplain and adjacent drift plain were monitored during summer 1987. Radio-marked broods were relocated an average of 22% of the time in the river channel, 22% in oxbow ponds, 43% in a large sewage lagoon complex, and 13% in basin wetlands. Four of the six broods hatched on the floodplain...

Abstract has not been submitted

We evaluated 3 techniques (air jet, flat skin, grab sample) to assess molt in dead waterfowl (green- winged teal [Anas crecca] and king eider [Somateria spectabilis]). The air jet technique was fast and required no specimen preparation. The flat skin technique required lengthy preparation time after which molt was assessed quickly. Both techniques underestimated the extent of molt (P 0...

We studied mallard (Anas platyrhynchos), gadwall (A. strepera), and blue-winged teal (A. discors) populations on 2 study areas of 22.6-km2 each in central North Dakota during 1976-81. Data regarding rates of return of females to natal or previously used nesting areas, nest site selection, and productivity of hens of different ages were collected from 1,166 nasal-marked and 2,142 banded...

Sago pondweed (Potamogeton pectinatus L.) is a submersed macrophyte of nearly cosmopolitan distribution. The plant is of worldwide importance as a waterfowl food but also can be a nuisance in irrigation canals and recreational areas. The plant reproduces by many different means, depending on habitat and environmental stress. Several genetic ecotypes have evolved. Most important as...

Review of: Ornithology. Frank B. Gill. New York : W.H. Freeman, 1990. ISBN: 0716720655.

Body mass of adult female and male sandhill cranes (Grus canadensis) increased an average of 17 and 20%, respectively, from early September to late October on staging areas in central North Dakota and varied by year. Increases in body mass averaged 550 and 681 g among female and male G. c. canadensis, respectively, and 616 and 836 g among female and male G. c. rowani. Adult and juvenile...

Abstract has not been submitted

We examined diets of canvasbacks (Aythya valisineria) breeding in southwestern Manitoba during 1977-81. Percent volume of animal foods consumed did not differ between males and females nor among prenesting, rapid follicle growth, laying, incubation, and renesting periods in females (mean = 50.1%). Tubers and shoots of fennelleaf pondweed (Potamogeton pectinatus) and midge larvae...

We correlated temporal changes in social groupings of canvasbacks (Aythya valisineria) breeding near Minnedosa, Manitoba, with an independent estimate of hen success during 1974-80. Roadside counts of pairs, lone males, and flocked males were made along transects at 5-day intervals, normalized to percentages to allow comparisons among years, and plotted to obtain measurements of selected...

We compared nutrients in reproductive and nonreproductive tissues of breeding Canvasbacks (Aythya valisineria) to assess the relative importance of endogenous reserves and exogenous foods. Fat reserves of females increased during rapid follicle growth and varied more widely in size during the early phase of this period. Females began laying with ca. 205 g of fat in reserve and lost 1.8 g...