f= 
46 
Table 3, -- Species Composition and Sex Ratio of Ducks Recorded During Ground 
Survey of Breeding Grounds in North Dakota - Spring, 1950 - 
Species Composition 
res 
. 
a 
« 
’ 







a % 
Species Male Female Total _ Total “Males 
Blue-winged teal 1762 1337 3099 33.8 31.7 
Pintail 1681 667 2348 26. 4 _ 30.2 
Mallard 701 359 1060 leh, Oe * -~ 12.6 
Shoveler 631 420 1051 11.8 11.4 
Gadwall 230 200 430 4.8 4.1 
Redhead 144 109 253 2.8 2.6 
Baldpate 103 83 186 2.1 1.9. 
Ruddy 106 73 _ 179 2.0 era S er 
Canvasback 119 53 172 1.9 2.1 
Scaup 74 39 113 aie 3 L.3 
Green-winged teal 4 3 7 : et pi 
Others 3 1 4 : 24 
Totals 5558 3344 8902 


Population Trends 
Comparison of the basic data from the 1949 and 1950 aerial counts indicates 
an increase of approximately 40 percent in breeding ducks in 1950. However, after 
applying correction factors obtained in the ground counts, the over-all increase 
indicated by the aerial survey is reduced to approximately 33 percent. 
Comparison of the data from comparable ground counts indicates an increase 
of approximately 18 percent in breeding pairs of ducks in 1950. ; 
On the basis of these data, it is concluded that the 1950 spring breeding 
populations of ducks in North Dakota was approximately 25-30 percent greater than 
that of 1949. 
