198 
nearly all the potholes, small lakes, and some larger lakes of 100 acres or more. 
Continued drought until mid-October has resulted in the loss of more than one 
half of those areas present during the mid-May surveys. 
The dry-up in the central and western sandhills was much less severe 
with only some small potholes lest from the 1954 season. Water levels in the 
larger lakes, controlled mostly by ground water, were generally good. The 
normal seasonal dry-up occurred leaving most permanent water areas with © 
average levels in mid-October. 
Breeding Population Trends 
Table I. - Sandhill Aerial Transect Data Summary. 
Square Miles Sq. Mi. Ducks Ducks Per Total Duck 
Strata* in Area Sampled Observed Square Mile Index** 
Eastern 
Less than 1/2 734 39.50 0 . 00 0 
Duck Habitat 
More than 1/2 3859 273.25 732 2.68 10, 342 
Duck Habitat 
Central 
Less than 1/2 1815 34.50 0 . 00 0 
Duck Habitat 
More than 1/2 2831 115.00 1189 10. 34 29,273 
Duck Habitat 
Western 
Less than 1/2 
Duck Habitat 2814 29.25 0 . 00 0 
More than 1/2 
Duck Habitat 4178 233, 00 2931 12.59 52,589 

* Each area was divided by all the possible flight paths that were 
more than one-half and those that were less than one-half 
within relatively abundant duck habitat areas. 
*x* Ducks per square mile x square miles. Counts made May 10-18, 
1955. Conservation Officer Ralph Von Dane, Pilot, U. 5. 
Game Management Agent W. G. McClure, and writer, 
observers, 
