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

Table 44. Average production and recruitment rates of young for 12 duck species,
Woodworth Study Area, 1965-81.


Table 44. Average production and recruitment rates of young for 12 duck species, Woodworth Study Area, 1965-81.
Species Average pair population (PP) Hen success rate (H) Averaged brood size at fledging (B)a Recruitment rate (R)b Averaged young produced per yearc
Mallard 53 0.25 5.7 0.49 53
Gadwall 68 0.30 7.3 0.76 104
Northern pintail 31 0.22 3.8 0.29 18
Green-winged teal 9 0.32 4.0 0.44 8
Blue-winged teal 225 0.33 5.9 0.68 307
Northern shoveler 29 0.25 5.0 0.43 25
American wigeon 11 0.31 6.0 0.69 15
Redhead 18 0.21 3.7 0.27 10
Canvasback 6 0.50 3.4 0.59 7
Lesser scaup 23 0.18 7.5 0.47 22
Ring-necked duck 1 0.39 6.8 0.92 2
Ruddy duck 20 0.32 3.6 0.40 16
Total 492 0.30 5.6 0.58 579
aAverage brood size at Class III brood size was used, or the nearest estimate, and it was assumed that very little duckling loss occurred between Class III brood size and fledging.
bR = HZB/2 where Z = 0.70 for survival of broods from hatch time to census periods (Cowardin and Johnson 1979).
cAverage young produced per year = 2 x R x PP.


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