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WATERFOWL BREEDING GROUND SURVEY IN NORTH DAKOTA 
Bernard A. Fashingbauer * 
Introduction 
The waterfowl breeding ground investigations conducted by the North Dakota 
Game and Fish Department in 1953 represent the 6th consecutive State-wide survey 
which has been carried on within the State. 
The purpose of these waterfowl surveys is to obtain information relative to the 
Spring migration, the breeding population and the resultant production which, when 
compared with similar data secured in other years, will determine the trends in the 
various aspects of waterfowl populations. 
With the exception of the assistance of an aerial observer from the Office of 
River Basin Studies of the Fish and Wildlife Service, all of the data were secured by 
personnel of the Pittman-Robertson Division of the State Game and Fish Department. 
Sampling Methods and Area Covered 
Techniques employed in censusing the 1953 breeding waterfowl population were 
identical to those used in 1952. Both aerial and ground censuses were conducted. 
The aerial census was conducted along 18 transects which traverse the State in 
an east-west direction and are located 12 miles apart in a north-south direction. 
The ground census was conducted along eight transects which traverse the State 
in a north-south direction. The east-west distance between the ground transects varies 
with the location of suitable roads, 
In both the aerial and ground inventories, all the game species of waterfowl 
observed within a 1/4-mile strip are tallied and geographically located, 
Each year the breeding pair census is begun immediately after the apparent 
completion of the spring migration. In 1953 the aerial and ground censuses were 
conducted concurrently in the period May 12 to May 25, inclusive. 
Aerially observed duck densities obtained by a random sample (slightly more 
than 2 percent) of the entire State serve as the basis in determining the breeding 
population index. The ground census provides information relative to the species 
composition and sex ratio of the waterfowl population. The sex ratio data permit the 
computation of a corrective factor to compensate for hens on the nest which are not 
observed during the aerial census. By applying the detailed information obtained 
during the ground census to the mass aerial data, the latter becomes more useful 
and reliable as an indication of the minimum breeding waterfowl population. The 
ground census is also used to tally available water areas. 
* James E. Sjordal, Field Biologist, assisted in compiling brood data, 
