Vol . 9, No. 3 
Page 5 
4. Responses of Bobwhi tes to Habitat Manipulation J. A . Ellis, J. A. Eastman 
Quail can be sexed and agud in the fall by plumage characteristics. Sex is 
determined by dimorphism of the head plumage. Young-of-the-year (juveniles) are 
distinguished from adults by the appearance of the seventh primary covert and by 
the progress of molt of the primary flight feathers. 
Harvested quail on the Dale and Forbes areas were sexed by park custodians, 
who removed one wing from each bird at the check stations. Wings were then aged 
by project biologists. Sex and age data for harvested quail on the two areas are 
presented in Table 4. 
Juvenile quail comprised over 80 percent of the harvests for all years (1963“ 
65) on both study areas. Although fall populations on the two areas were consider¬ 
ably lower in 1965 than in 1964 and harvests reflected a similar trend, the percent 
age of juveniles in the harvest increased from 1964 to 1 965 on both areas. Poor 
survival of adults in the summer and fall of 1 965 , rather than reproductive success 
was thought to have influenced the increase in percentage of juveniles in the bag 
i n 1 965 . 
Disproportiona1 sex ratios are common among bobwhite juveniles and adults. 
Most published studies report males outnumbering females. On the Forbes Area, 
males have consistently outnumbered females in the adult samples. Among the 
juvenile segments of the kills, however, sex ratios have favored females. Similar 
trends in sex ratios were noted in kills on the Dale Area, with the exception of 
1963* In that year, adult sex ratios favored females, while juvenile sex ratios 
favored males. 
Studies generally agree that mortality of females during breeding season 
accounts for the unbalanced sex ratio favoring males among adults. The consistent 
unbalanced sex ratio favoring females among juveniles (for 3 years on the Forbes 
Area and for 2 of 3 years on the Dale Area) may indicate that the sex ratio favors 
females at hatch, or that juvenile females are more vulnerable to hunting pressure 
than juvenile males. The latter premise seems unlikely. 
Table 4. Sex and age ratios among quail harvested from two Illinois areas, 1 36 3“65 
Adu 1 ts 
Juveni1es 
A1 1 Quai1 
A rea 
cfcf 
?? 
Percent 
Ma 1 es 
dtr 
9? 
Percent 
Ma 1 es 
Percent 
Juveni1es 
Forbes 
1963 
12 
1 1 
52.2 
63 
80 
44.0 
86.1 
1964 
29 
20 
59-2 
87 
110 
44.2 
80.1 
1965 
8 
7 
53.3 
38 
46 
45.2 
84.8 
Tota1s 
49 
38 
56.3 
188 
236 
44.3 
83.0 
Dale 
1963 
12 
16 
42.8 
82 
52 
61 .2 
82.7 
1964 
15 
12 
55-6 
80 
95 
45.7 
86.6 
1965 
10 
2 
83.3 
46 
52 
46.9 
89.1 
Totals 
37 
30 
55.2 
208 
199 
51.1 
85-9 
