Vol * 24, do. 12 
Page 2 
Correlations between adult population size and recapture rates of different 
age classes may be an indication of social regulation. If social factors are 
important in density regulation, we would expect a negative relationship between 
survival and densities. P.ecapture rates of resident (£0.5 years old when first 
captured) adult male and female fox squirrels were not significantly (P_ > 0.05) 
related to the number of squirrels present. Immigrant (>0.5 years old when 
first captured) adult survival, however, was negatively related (P < 0.05) to 
the number of adults, most strongly to the number of females. Juvenile survival, 
surprisingly, was oositively correlated (£ < 0.05) with the number of resident 
adults—total males and total females. Subadult and yearling female recapture 
rates were negatively related to the number of males and the number of resident 
females (P < 0.05). Densities and recapture rates of subadult males were not 
significantly related; whereas recapture rates of yearling males was negatively 
related to the number of adult females and positively related to the number of 
resident males (P_ < 0.05). Survival from birth to 0.5 year was negatively 
related to the number of resident females and positively related to the number 
of adult males (P < 0.05). 
v/ e would expect several significant relationships by chance alone given the 
large number of correlations performed. Our problem is selecting the biologically 
meaningful relationships. Apparently, the number of adults, especially females, 
negatively influenced recapture of several age~sex classes. Hales had less 
influence than females on recapture; sometimes their influence was positive. 
Until further work is performed, however, we can make few definite conclusions. 
Presently we are running a field experiment to test the hypothesis that the 
presence of adults influences the survival of all age classes, especially the 
young. 
Responses of Prairie Chickens to Habi tat Manipulation ' ,_ 66~R P..L. V/estemeier, 
J.E. Buhnerkempe 
Wildlife biologists usually study cover preferences of wildlife to increase 
wildlife populations through habitat management. In our case, however, a. 
comparison of cover preferences is needed to maximize use of the sanctuaries by 
prairie chickens and minimize benefits to pheasants. Increasing numbers of 
pheasants on the sanctuaries underlies the need for this study (it'fPL 24(11) :2"3)» 
Annual nest searches on sanctuaries in Jasper County provide insight on 
comparative cover preferences by the 2 species. 
Among the 4 major grass types on the sanctuaries, densities per 10 acres 
for 53-0 prairie chicken nests were brome, 2.6; timothy, 1.5; redtop, 1.3; and 
prairie grass, 0.9. The densities per 10 acres for 72 pheasant nests were 
prairie grass, 0.4; brome, 0,3; timothy, 0.2; and redtop, 0.1. Thus, lowest 
densities of prairie chicken nests but highest densities of pheasant nests were 
found in prairie grasses (switchgrass, Indiangrass, and big bluestem). 
