Table 6 shows the number of doves seen and heard during call counts 
in 1950. A distinction has been made between birds seen while driving 
between the one-mile stops and those actually seen (and not heard) during 
the 3-minute listening periods. It is believed that birds under the 
column "doves seen driving" are comparable with data from early morning 
roadside counts whereas birds recorded under "doves seen stopped" in- 
clude only those individuals which would not have been recorded had the 
car been in motion. Of the 336 doves seen during these call counts, 
18h or 54 percent of the birds were seen while stopped. 
An interesting comparison can be made between birds recorded on 
calling counts and those recorded during pure roadside counts. From 
Table 6, let us consider only the figures for pre-sunrise through the 
third hour for comparison with roadside data from part "b" of Table l. 
All call count data for these "four" hours average 111 doves per 100 
miles as opposed to an average of only 94 doves per 100 miles during 
roadside counts (Table 1). If consideration is made for the fact that 
it takes three times as long to cover the same distance in making call 
counts, a factor of three should be applied to the figure "9%." ‘The 
latter figure (9%) then would be 264 doves per 100 miles on roadside 
counts as compared with 111 per 100 miles recorded during call counts. 
If an additional factor of is introduced to compensate for the time 
of day when roadside counts were made we have, then, an average of 71 
doves per 100 miles; this is still only 6 percent of the average figure 
for call counts (see page 17 for explanation of factor of 24). These data 
show that call counts plus the doves seen during these counts give far 
more information on abundance of doves during the breeding season than 
roadside counts alone, even when all possible allowances are made in 
computing roadside counts. 
During the morning period (through third hour after sunrise) when 
call counts were made in 1950, 686 doves were recorded: 80 percent were 
tabulated at one-mile stops and the remainder while driving from one 
stop to another. Fven if an allowance (factor of 3) is made for the 
time element for birds seen while driving, the total number of birds 
recorded while stopped would still be far in excess of those seen while 
driving. For all the major areas studied there was an average of lll 
doves per 100 miles traveled, 6) doves per 100 miles being calling in- 
dividuals. 
23 
