Vol. 16, No. 10 
Page 3 
Responses of Bobwhites to Habitat Hanipul at ion J . A. Ellis 
Wings from 245 quail harvested in 1972-73 on the Dale Area were sexed and aged 
according to plumage characteristics. Juveniles comprised 80 percent of the sample. 
The percentages of cocks among the adult and juvenile segments were 56 and 49, 
respectively. The young:adult hen ratio was 9-4:1. 
Seventy-eight percent of the 3 1 6 wings comprising the sample from Forbes in 
1972-73 were juveniles. Sixty-five percent of the adults and 51 percent of the 
juveniles were cocks. The young:adult hen ratio was 10.3:1- 
These sex and age data from the 1972-73 harvest deviate slightly from the 
long-term mean for 8 years, 1964-71- More than 2,000 wings from each area were 
examined during that period. Juveniles comprised 85 percent of the sample from 
Dale. Sixty-three percent of the adults and 49 percent of the juveniles were 
cocks. The young:adult hen ratio was 18:1. 
Juveniles comprised 82 percent of the sample from Forbes. The percentages of 
cocks among the adult and juvenile segments were! 60 and 51, respectively. The 
ratio of young per adult hen was 12:1. 
^ Responses of Prairie Chickens to Habitat Manipulation R. l. Westemeier, 
D. R. Vance 
During the 10-year period of 1 963 -72, the rate of predation and abandonment of 
prairie chicken nests at Bogota ranged from 7 .1 to 50.0 percent, with a mean of 
34.2 percent for 310 nests of known fate. (Nest losses due to farm activities are 
excluded in this report.) Among 106 unsuccessful nests found during this period, 
86 (81.1 percent) were found destroyed by predation and 20 (18.9 percent) were judged 
to have been abandoned. The estimated number of eggs per unsuccessful nest ranged 
from 1 to 14 and averaged 5-4 for the 1963-72 period. 
In 1973, however, 73-0 percent (54 nests) of all nests found were unsuccessful 
due to predation or abandonment. About 93 percent of the unsuccessful nests were 
destroyed by predators. The mean number of eggs per unsuccessful nest in 1973 
was estimated as 7-2 and ranged as high as 16 eggs. 
The rate of predation and abandonment of nests in 1973 was over twice as 
high as the mean for the preceding 10 years. Predation or abandonment in 1973 
occurred at later stages of laying or incubation than were average for 1963 - 72 . 
Possible reasons for the poor nest season of 1973 were discussed in the previous 
report (MWRL 16(9):3)- Between 1963 and l 969 , hen kills were recorded at only 2 
of 33 nests (both in 1964) that were unsuccessful because of predation or abandon¬ 
ment. In 1970, 1972, and 1973, hen kills were noted at 23.8 percent, 18.8 percent, 
and 13-0 percent, respectively, of the nests that were unsuccessful due to predation 
or abandonment. Thus, predation on nesting hens per se has increased to noteworthy 
levels during the past 4 years and does not appear exclusively related to factors 
responsible for the poor nest season of 1973 . 
