Decrease of the mourning dove, an important game bird of the United States, has been noted recently in eastern and southern states. In Iowa, the dove is among the commonest of breeding birds, and observations in Cass County, Iowa, during 30 months of 1938, 1939 and 1940 revealed that the county production was high, averaging an estimated 200,000 young yearly from 73,000 adults. About 2 percent of the summer residents is believed to have wintered in the county.

Detailed investigations at Lewis, at 14 farmyards and at 6 other habitat types, brought under observation nearly 4,000 nests. The preferred types of trees were elms and conifers. The average success of nestings was 50 percent, an average of 55 percent of the eggs was hatched, and an average of 82 percent of young left the nests yearly. The peak of nesting activity came during the middle of June, followed by a slump in August and a slight increase in the fall. The robin-dove relationship was greatly of advantage to the dove in nesting.