
Table II - Species Composition of the Colorado Breeding Population, 1956* 

Number | Species Composition % 
Species | 1954 1955 1956 1954. 1955. 1956 
Mallard 11,295 9,633 11,027 70.4 63.9 61.7 
Blue-winged Teal 886 600 1,010 5.5 4.0 5.6 
Pintail | | 873 750 710 5.5 5.0 4.0 
Gadwall 852 1,874 1,495 5.3 12.4 8.3 
Baldpate 552 211 376 3.4 © 1.5 2.1 
Shoveler 542 220 387 3.4 1.5 2.2 
Cinnamon Teal 442 509 862 2.8 3.4 4.8 
Green-winged Teal 220 407 406 124 Ze 2.3 
Redhead 109 352 807 0.7 2.3 4.5 
Scaup 99 369 556 0.6 2.4 33.1 
Ruddy Duck 48 44 12 0.3 0.3 0.1 
Bufflehead - - 12 > - 0.1 
American Merganser 114 105 222 0.7 0.7 1.2 
fn n= Eee 
Totals 16,012 15,074 17,882 100.0 100.0 100.0 

* Data derived from permanent transect records for the 1956 season. 
Data are corrected for unidentified pairs. 7 
Species composition of the duck breeding population was very similar to 
past years (Table II). Mallards still make up the bulk of the breeding birds 
(41. 7 percent) and no other species make up more than 10 percent of the total 
number. | . 
Considering all areas, 1956 duck breeding populations show an increase 
of 18.6 percent over 1955, and 11.0 percent over 1954. 
The Yampa Valley--Brown's Park goose flock showed a good increase in 
population this year over last, but still under the previous years of 1952, 1953, 
and 1954. | 
Conclusions - 
In view of the increase in breeding population in Colorado this year, and 
the favorable water conditions, it is estimated that the fall flight from Colorado 
will be somewhat larger than in 1955. 
