Some of the shortcomings of the data available to fulfill 
these assumptions are as follows: (1) The distribution of banding 
does not always represent the distribution of the dove population; 
(2) unmeasured biases in the call-count census and possible 
variation in productivity between management units obscure the 
relation between the breeding index and the actual population 
(Southeastern Association, 1957); and (3) little is known of the 
variation in rate of reporting bands faund on shot birds (Atwood 
and Geis, 1958). 
It is clear that a real job lies ahead in eliminating or 
evaluating the biases that tend to invalidate the procedure followed. 
MANAGEMENT UNITS AND BORDER STATES 
Thirty States now class mourning doves as game birds 
and have open hunting seasons (figure 1). Several additional 
States are expanding their dove-research programs and are 
considering hunting seasons, 
Figure 2 shows the tentative division of the United States 
into three management units. Within each of these units--Eastern, 
Central, and Western--production and harvest areas appear to 
be more closely related to each other than to production or harvest 
areas in another unit, These units most nearly meet the criteria 
of an ideal management unit: A unit that produces the doves it har- 
vests and does not produce doves that are harvested by other units.. 
Border States between the Eastern and Central units are 
Wisconsin, Illinois, Missouri, Arkansas, and Louisiana. Figure 2 
illustrates where birds banded in these States are shot and where 
the hunting kill of these border States originates. In these calcu- 
lations, the five border States are considered neutral with respect 
to their assignment to either the Eastern or the Central manage- 
ment unit. For example, Wisconsin, a non-hunting State, contri- 
buted 54 percent of its banded doves to the harvest in the Eastern 
unit and 21 percent to that in the Central unit, on the basis of 24 
band recoveries. The remaining 25 percent was shot in the border 
States or in Mexico or Central America. Recoveries of doves 
banded in Illinois, a hunting State, were distributed as follows: 
35 percent to the Eastern unit, 6 percent to the Central unit, and 
59 percent to the border States, Mexico, and Central America. Of 
the Illinois hunting kill, 5 percent (on the basis of weighted band 
recoveries) originated in the Eastern unit, outside the border 
States. Hence, Wisconsin and Illinois appear to fall rather definitely 
into the Eastern unit. 
