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Table I, - Waterfowl Breeding Areas and Samples, Colorado - 1953 

Breeding Grounds AREA Sampling Method * 
Total Sample Percent 
. Sq. Mi. Sq. Mi. of total 
North Park 611 55 9.0 Aerial 
South Platte Valley 1,407 70 5.0 Ground and Aerial 
Cache la Poudre Valley 343 36 10.5 Ground and 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 
San Luis Valley -- -- -< Aerial 
South Park -- -= -- Ground and Aerial 
* Breeding-pairs and lone birds recorded by species and cover types 
in both ground and aerial coverages. Vehicle employed for ground 
travel; inaccessible areas walked, Cessna 170 and super-cub planes 
used for aerial work, crew consisting of pilot and observer. Identical 
forms used for recording data in both methods of coverage. 
The eastern plains were affected differently. There, the mild winter and early 
Spring was generally favorable to the early movement and nesting. of ducks. It is 
believed that nesting was earlier this year than for the past 5 years as a result of 
these conditions. 
Water levels were generally low in reservoirs, sloughs, and streams throughout 
the State. Intermittent potholes on the eastern plains, which in wet years furnish 
additional nesting habitat, have no water this year. Although not disastrous, this 
State-wide decrease in water has resulted in reduced production for all areas in 1953, 
Discussion of Data 
The current report on waterfowl conditions is, perhaps, more confusing than 
any previous report has been, or any future report will be. This is due to the two 
types of information that have been gathered this year--trend data, and total production 
estimates, . AS previously explained, some areas in the State still remain to be surveyed 
on the basis of total production. The only information obtainable from these areas, 
therefore, is a comparison of production on a trend basis. For this reason, each 
breeding ground will be discussed separately and in summary form, and all known 
production will be briefly summarized at the end of the report. 
North Park 
This high mountain park consisting of approximately 611 square-miles is located 
in the north-central portion of the Colorado mountains. An attempt has been made, 
this past summer, to determine the best waterfowl census method for this area. To 
accomplish this, a series of 4 flights of randomly selected transect routes were made, 
and 2 ground counts of selected areas over all habitat types represented in the Park. 
Comparison of these methods has revealed that: (1) Aerial breeding-pair counts are 
satisfactory; (2) aerial brood counts are unSatisfactory; and (3) ground brood counts 
will give a better estimate of production than aerial brood counts if a good sample of 
each habitat type is taken. The following report is based upon an aerial breeding -pair 
count and a later ground brood count. Admittedly, the sample on which the brood 
