172 
A summary of sampling methods and areas is given in Table I. 
Table I - Waterfowl Breeding Areas and Samples, Colorado - 1952 
Rm enn en nn nnn SO, 
AREA 
pear eS Pe tr ete eee ee LL 
Breeding Grounds Total Sample Percent of Sampling Method * 
Sq. Mi. Sq. Mi. Total 
Northeast Colorado 
Cache la Poudre Valley 36 36 100 Ground and Aerial 
South Platte Valley 1,407 - - Aerial 
North Park 815 30 3.6 Ground and Aerial 
San Luis Valley - - - Aerial 
Yampa River Valley 220 22 10.0 Ground 
Brown's Park 15 15 100.0 Ground and Aerial 
White River Plateau 360 18 5.0 Ground 

* Breeding pairs, lone birds, and broods recorded by species and by 
cover types in both ground and aerial coverages. Vehicle employed for ground 
travel; inaccessible areas walked, Cessna 140 and Cessna 170 planes used for 
aerial work, crew consisting of pilot and observer. Identical forms used for 
recording data in both forms of coverage. . 
Weather and Water Conditions 
Climatological data and phenological records indicate that the 1952 spring 
season in Colorado was about 10 days earlier than in 1951. This circumstance 
apparently resulted in earlier northward migration and probably earlier nesting 
than in the preceding year. 
The earlier season, however, appears to have been counter-balanced by 
flooding losses caused by unprecedentedly heavy runoff, which adversely affected 
both east and west slope streams. Along the Yampa River especially such losses 
were heavy; and apparently heavier than normal spring flooding was common 
throughout the State. It now appears that flooding losses were largely compensated 
for by renesting. 
Except for flooding and a three-week drought in northeast Colorado, 
weather conditions have been generally favorable to waterfowl nesting, Water 
levels in practically all lakes, reservoirs, and marshes are higher than normal, 
the only loss from this source being due to the drying up of shallow depressions 
in the northeastern part of the State, which ordinarily are too dry for nesting 
purposes. 
Discussion of Data 
For convenience the six breeding grounds considered in this report will 
be treated separately and in summary form. 
