Northern Prairie Wildlife Research Center
Mallard Recruitment in the Agricultural Environment of North Dakota
The study area was an area of 10,041 km2 in central North
Dakota (99°00.0'-100°22.5'W long. and 47°00.0'-47°52.5'N lat.) (Fig. 1). It
included portions of the Missouri Coteau and Drift Plain biogeographic provinces
(Stewart 1975) in about equal proportions. The Missouri Coteau, composed primarily
of rolling stagnation moraine and outwash plains, contained 14.6 ha/km2
of wetland. The Drift Plain an area of glacial drift with much less relief than
the Coteau, contained 6.3 ha/km2 of wetland (Cowardin et
al. 1981). The primary land use was for the production of small grains, sunflowers,
hay, and pasture for beef cattle. Most of the pasture was native mixed-grass
prairie. In recent years there has been a continuing trend in land use away
from pastureland and toward cropland.
Annual rainfall averages 44.3 cm/year. Mean minimum temperature is 2.8 C
and mean maximum is 11.1 C. The growing season is 119 days (Seago et al. 1970).
Climatic fluctuation, especially in rainfall, is great and is reflected by
the number of ponds available to waterfowl during the breeding season. Our
study included 2 dry years, 1977 and 1980, and 2 wet years 1978 and 1979 (Table
Table 1. Variation in temperature, precipitation,
and density of ponds on a 10,041-km2 study area in
central North Dakota from 1977 to 1980.
||Departure from mean temperaturea
Apr-Jun (Degrees C)
||Departure from mean precipitationa
temperature and precipitation data obtained from Jamestown, North   Dakota,
situated 17 km east of the southeast corner of the study area.
from aerial photography of 66 3.22-km2 plots.
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