Waterfowl Production on the Woodworth Station
in South-central North Dakota, 1965-1981

Table 40. Mean cumulative brood size of 12 duck species by age class and month,
Woodworth Study Area, 1965-81a.


Table 40. Mean cumulative brood size of 12 duck species by age class and month, Woodworth Study Area, 1965-81a.
  Class I Class II Class III 17-year mean, all classes
Species July August July and August July August Julu and August July August July and August July August July and August
Dabbling ducks
Mallard 6.3 6.1 6.2 5.4 5.5 5.5 --b 5.7 5.7 5.9 5.7 5.8
Gadwall 8.1 6.4 7.3 7.8 6.9 7.0 -- -- -- 8.0 6.6 7.2
American wigeon 7.9 5.0 7.3 -- 5.6 5.6 -- 6.0 6.0 7.9 5.5 6.6
Green-winged teal 7.0 4.8 5.5 -- 6.3 6.3 -- 4.0 4.0 7.0 5.1 5.4
Blue-winged teal 7.5 5.2 6.9 7.7 5.6 6.7 6.5 5.8 5.9 7.6 5.6 6.7
Northern shoveler 6.7 4.4 5.8 6.3 5.3 5.7 7.5 4.4 5.0 6.6 4.9 5.6
Northern pintail 9.3 3.0 6.6 4.3 3.3 3.9 1.0 4.5 3.8 5.3 3.6 4.4
Total dabbling ducks 7.6 5.8 6.9 7.3 5.8 6.5 6.3 5.6 5.7 7.4 5.8 6.6
Diving ducks
Redhead 7.7 6.0 6.6 6.7 5.2 5.6 -- 3.7 3.7 7.5 5.6 6.2
Canvasback 5.5 5.0 5.4 4.8 4.7 4.7 -- 3.4 3.4 5.0 4.5 4.7
Lesser scaup 8.0 6.5 7.0 -- 7.9 7.9 -- -- -- 8.0 7.4 7.5
Ring-necked duck 8.0 4.0 6.0 10.0 5.5 7.0 -- 8.0 8.0 9.0 5.8 6.8
Ruddy duck 4.9 5.2 5.1 6.8 3.7 4.0 -- 5.7 5.7 5.2 4.5 4.7
Total diving ducks 6.2 5.7 5.9 5.4 5.5 5.5 -- 4.4 4.4 5.9 5.5 5.6
Total broods 7.4 5.7 6.7 7.1 5.8 6.3 6.3 5.5 5.6 7.2 5.7 6.4
aOnly broods with complete counts.
bIndicates no data.


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