ABSTRACT 
Mourning dove population indexes declined from 1970 to 1971 by 
5 percent in the Eastern Management Unit, by 4 percent in the Central 
Management Unit, and by 2 percent in the Western Management Unit. The 
changes were not statistically significant. The 1971 indexes were 
below the 10-year means, 1961-70, by 7 percent in the Eastern Unit, 
15 percent in the Central, and 25 percent in the Western. Regression 
analyses of the call-count data for 1961-71 indicate a statistically 
significant downward trend in dove breeding populations in all man- 
agement units; mean rates of decline were 1 percent a year in the 
Eastern Unit, 2.5 percent a year in the Central, and 4.4 percent a 
year in the Western. 

Changes in the population indexes are described by State and 
physiographic region. The 1971 indexes were generally lower than 
1970 in the southern two-thirds of the United States, and generally 
higher in the northern third. Regression analyses of 11 years' data, 
1961 to 1971, indicate a statistically significant downward trend in 
population in much of the area represented by the northern Great 
Plains and Pacific border and southern border States. Trends are 
Significantly upward in several scattered mid-latitude States. 
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