210 
Duck Population Tmends Expressed in Breeding Pairs per Square Mile in 
North and South Dakota 
s+ ttep i & 
ae . ~ SS Sag endigeeee om 
“> lial 
2 ae 
gi af 
ad 2” ae 
| ae pe on fa - 
a anos oy 
bs gS 
v 
he 
a 
ao aliarg 
un) | IVA She 
Mi 
» | 
| Gadwall 
| Redhead ——=s ati! 
. Ruddy duck . 3 
1948 1949 1950 1951 1952 
In general it can be stated that the breeding pair population of waterfowl in the 
Dakotas has varied directly with the number of water areas per square mile during 
the past five years. It should be possible to determine the closeness of this 
correlation between water areas and ducks if data from the entire breeding grounds 
are assembled. Size of water areas is also important, the smaller areas being more 
heavily populated in a unit basis. The number of water areas per square mile is 
more important than the total acreage per square mile. 
Table VIII - Brood Averages -- Class III Only (North and South Dakota Combined) 
Species 1949 1950 1951 1952 
B-w. teal 7.54 7.37 7.74 7.56 
Pintail 5.69 5.93 5.73 6.67 
Gadwall 7.40 8.29 7.75 6.80 * 
Mallard 6.67 6.25 7.24 | 6.62 
Shoveler 6,54 7.31 7.37 5.50 * 
Ruddy duck 6.50 5.00 - 4.80 
Redhead ‘6.25 - 74.38 7.00 
Lesser scaup - 7.00 - 6.18 

* Too few broods to give accurate averages. 
