Book excerpt: U.S. mourning dove population indexes increased by 4% from 1969 to 1970 in the Eastern Management Unit, but declined 2% in the Central Management Unit and 11% in the Western Management Unit. The changes were below the 10-year means, 1960-69, by 3% in the Eastern Unit, 15% in the Central, and 27% in the Western. Regression analyses of the call-count data for 1960-70 indicate a statistically significant downward trend in dove breeding populations in all management units; mean rates of decline were 1% a year in the Eastern Unit, 3% a year in the Central, and 4% in the Western