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Table I - Average Brood Size by Age Classification in Eastern Washington 
aA SP a fy eS SS 

Class I Class II Class III 
No. Average No. Average No. Average 
Species Broods Size Broods’ Size Broods’ Size 
Mallard 79 1255 49 6.65 88 6.09 
Baldpate 17 6.23 26 6.26 49 6.51 
B-w. teal 23 7.39 22 13% 19 7.26 
Gadwall 28 7.07 30 7.43 13 6.69 
G-w. teal 22 7.59 3 4.66 19 5.31 
Shoveler 9 8.66 7 5.85 21 55 
Pintail 20 4.45 22 6.09 30 4.86 
Redhead 21 6.19 1l 6.45 3 6.00 
Ruddy duck 12 4.58 14 6.64 4 5.25 
Scaup 12 6.75 10 7.50 0 - 
Unidentified 16 6. 87 13 6.69 19 5.31 
Total 259 6, 87 207 6.78 270 5.96 
Central Washington 
Although the breeding population was slightly less in 1952, more broods 
appeared in all areas of central Washington. Favorable nesting and water conditions 
were apparently responsible for the increased brood success. The total fall 
population was determined to have increased by 14.5 percent in 1952, fixing the 
total population index at 66,910 ducks and coot. 
With the development of the Columbia Basin in Washington, the importance 
of waterfowl production within irrigation projects becomes more pronounced. 
Existing irrigation lands, almost all of which are located in the Yakima River Basin 
of central Washington, have been of relatively moderate importance in the State-wide 
production summary. However, the Columbia Basin which will exceed the Yakima 
projects in size by almost 5 times upon completion, should develop into a major 
waterfowl production area. In anticipation of production possibilities in the Columbia 
Basin, the southcentral Washington irrigation systems were divided into 5 units based 
on waterfowl utilization and allied land and water uses. The most important irriga- 
tion unit in this region is the irrigable lands of the Yakima Indian Reservation, 
with an average of 28.89 resident waterfowl and 7.48 broods per square mile in 
1952, This land is mostly flat or gently rolling bottomland with a checker-board 
pattern of irrigation canals, approximately 244 miles of drainage ditches, and is 
traversed by several winding, sluggish streams. Low crops and pasture land are 
the most important crops grown in this unit. 
Again in 1952, 17 species of ducks, coot, and Canada geese utilized 
central Washington breeding areas. Mallards, as usual the most abundant species, 
increased their relative abundance in 1952. Wood ducks were again second in 
relative breeding importance after relinquishing this position to redheads in 1951. 
The erratic redhead breeders decreased by almost 40 percent in 1952. Decreased 
Populations of blue-winged teal, pintail, Barrow's goldeneye, and coot were also 
evident. 
