Population Trends 
Comparison of 1949 data with that of 1948 indicates a substantial increase 
of waterfowl in 1949. 
An increase of approximately 27 percent in total ducks is indicated by 
comparing raw data from the 10 aerial strips covered in both 1948 and 1949. 
By ground counts, an increase of approximately 15 percent in breeding 
pairs is indicated when all 1948 and 1949 ground counts are compared. When 
only those counts made in a comparable manner both years ars considered, an 
increase of approximately 18 percent in breeding pairs is shown. 
When all indicators are considered together in the light of their rela- 
tive reliability, it is believed that the duck breeding population of North 
Dakota in 1949 was approximately 25 percent greater than that of 1948. 
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