143 
WATERFOWL BREEDING GROUND SURVEY IN NORTH DAKOTA - 1950 
‘Brandt V. Hjelle 
Introduction 
The third annual State-wide survey-of migratory waterfowl breeding grounds, 
carried out cooperatively by the Branch of Game Management and Office of River Basin - 
Studies of the Fish and Wildlife Service, and the North Dakota Game and Fish Depart- — 
ment, was completed during the latter part of May and the first part of June, 1950, 
The survey included: (1) An aerial survey of the entire State on an equal 
basis for the purpose of determining mass waterfowl populations; and (2) A State-wide 
ground survey made in as random and complete a manner as possible for the purpose 
of obtaining information as to species composition and observed sex ratios, and also 
to furnish indices to waterfowl populations and waterfowl habitat. 
The Aerial Survey 
“The spring of 1950 brought an unusual increase in surface water present in 
a large portion of North Dakota. This condition increased the time and effort required 
to obtain a satisfactory water and waterfowl inventory on the 17 one-half mile wide 
sample strips used in the 1948 and 1949 surveys to such an extent, that it was soon 
decided to limit the 1950 survey to only an inventory of ducks on the north one-half of 
the previously selected sample strips. Accordingly, the major part of the 1950 survey 
was done on a quarter-mile basis, rather than a half-mile basis as was done in 1948 
and 1949. 
The Game Management Division of the Fish and Wildlife Service, using a 
Grumman 'Widgeon', covered strips 3, 7, 11,.and 15, on a quarter-mile basis. 
The Office of River Basin Studies, using the same crew and type of plane 
as used in the previous surveys, again covered strips 6 and 9, but this year ona 
quarter-mile basis. 
The Federal Aid Division of the North Dakota Game and Fish Department, 
using in large part the same planes and crews used in the previous survey, covered 
the remaining strips, all of which were done on a quarter-mile basis, except for 
strips 14 and 15, and that part of 16 west of the Missouri River, which were again 
covered on a half-mile basis. 
Because of an unusually late spring, this year's survey was made about two 
weeks later than that of 1949. The 1950 aerial survey was begun on May 21, with the 
greater part being finished by June 9. However, strips 6 and 9 and the west part of 
strips 12 and 13 were not completed until June 13. 
It is believed that the timing of this year's survey in general is such that it 
is comparable with the surveys of 1948 zn aie 
Except for the reduction in sample size and the elimination of water area 
data,’ techniques and procedures were essentially the same as in previous surveys 
and are fully explained in the 1948 report. 
