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Table 6, -- Brood Averages By Age Classes 
ee 
l 11 111 All Total Broods 
Speci =: ‘ 
Blue-winged teal 1949 8.60 7.76 7.54 8.11 577 
1950 8.21 -. ° 7.75 7.37 7,80 850 
Pintail 1949 5.69 _ 4.97 5.69 5.50 133 
1950 5.20 5.52 5.93 5,70 331 
Gadwall 1949 7. 86. 7.27 7.40 7.67 153 
a 1950 » 7.91 | 7.81 8.29 7.94 218 
Mallard 1949 6.97 6.77 6. 67 6.82 | 130 
1950 7.05 7,00 6,25 6. 80 193 
Shoveler 1949 7.13 6,43 6.54 _ 6.79 62 
: 1950 7.98 7.00 7.31 7.57 116 
Ruddy duck 1949 6.20 5.50 6. 50 6.13 38 
: 1950 6.61 4.83 5.00 6.22 67 
Redhead _ 1949 7.00 6.50 6.25 6.72 29 
: we 1950 7.00: 7,40 -=-- 7.08 50 
Canvasback 1949 6.93 4.20 6, 64 5.32 34 
1950 4.25 5.64 - 6,20 5.22 46 
Baldpate 1949 6.71 7.11 7. 66 6.96 26 
1950 7.24 6.50 5.50 7.15 33 
Lesser scaup | 1949 9. 60 6.00 won 7.50 16 
1950 7.77 8,45 7.00 7.97 31 
All Species 1949 7.79 7.03 6.97 7.40 1198 
1950 7,47 7.21 6. 83 7.20 1936 
Total Number 1949 610 289 299 1198 
of broods 1950 857 — 420 659 1936 
, Only in the case of the teal were there enough broods counted to warrant a 
comparison between states. Note how closely the brood averages agree between 
North and South Dakota in the following tabulation. 
Blue-winged Teal 
1 11 111 All 
North Dakota 8.41 (160) 7.68 (102) 7.33 (174) 7.81 (436)* 
South Dakota 8,04 (182) 7.81 (108) 7.43 (124) 7.80 (414)* 
* Numbers in parenthesis indicate nuniber of broods counted. 
The fore-going Fable indicates that for all species brood averages were a 
bit higher in 1949 but a larger proportion of Class 111 broods were counted in 1950. 
Actually, the only true comparison is between Class 1 and Class 111 broods. Using 
Class 111 broods only, we finda difference of about 0.14 ducklings per brood between 
1949 and 1950, or aloss of 2 percent. It is likely, however, that no waterfowl census 
can be accurate enough to measure this small a percentage change. 
