
Table II - Waterfowl Breeding Population Trends 
1956 aerial index including non-breeders. .. 123,639 


1955 aerial index including non-breeders ... 92,204, change- 1955 to 1955 +434,.14 
Average, 1954-55 aerial index............ 123,166, change-to 1956 -10.4% 
1956 breeding Guiele TNAES Re ose os ee ee Hoe es 94, 949 
1955 breeding duck indem.....as%-ssesbe ee 101, 864, change - 1955 60 1956 - 6.89% 
eee 
- Table III - Species Composition and Trends* 
% of '56 1955 % Change 

Species Eastern Central Westernt -Over:rall Index Index to 1956 
Mallard 3,887 10,493 11,455 25, 835 27.2 231,998 ~- 19.2 
Gadwall 412 2,229 4,995 7,636 8.0 10, 743 - 28.9 
Baldpate — 930 631 182 1, 743 1.8 1,733 + 0.6 
Pintail 1,812 3, 644 6,402 11, 858 12.5 10, 866 + 9.1 
G.W. Teal 552 151 703 O. 7 918 - 23.4 
B.W. Teal 7,347 11,156 11,647 30,150 31.8 92,989 - 8.6 
Shoveler 1,662 634 2,905 5,201 5.5 5,410 - 3.8 
Redhead 1,427 2,915 4,342 4.6 4, 841 - 10.3 
Canvasback 1,701 1. Fo 1.8 526 +223.4 
Scaup 140 1,115 2,267 3, 522 4.7 1,023 +244. 3 
Ruddy Duck 135 319 1,653 2,107 oat 442 +376. 7 
Cinnamon Teal 151 151 0.2 
Goldeneye io 59 
Bufflehead 316 
—eeeeeeeEeEeEe———eEeEEeE————————EE———ES——SS—————EE——————————————————————— 
Total 16,877 31,950 46,122 94,949 100.0 101, 864 - .6.8 
SS eee eee ———————————SSS————S——— 
* The species composition was determined by ground counts made 
immediately following the aerial counts. Species Indices are 
corrected for non-breeding ducks and for nesting hens as repre- 
sented by lone males on territory. 
40 
