when production of young exceeds natural mortality, this popula- 

 tion could sustain a greater kill by hunters without undue deci- 

 mation. If this be true, a more efficient utiHzation of the prairie 

 chicken as a resource could result, and high populations, which 

 may elicit complaints from farmers and ranchers, could be avoided. 



Changes in Age Composition 



The age ratios, as revealed by the examination of birds killed 

 by hunters (see Table 8), reflect the weather conditions of the 

 three breeding seasons, and the average size of broods seen in 1950 

 and 1951 (cf. Figures 7 and 8). The productivity of the greater 

 prairie chicken, as shown in Table 8, falls far short of that of the 

 bobwhite (Bennitt, 1951:32), which experience has shown is a 



Table 8. The 0.9546 Confidence Limits of Certain Population Char- 

 acteristics OF THE Greater Prairie Chicken, From Birds Examined in 

 THE Autumn, 1950, 1951 and 1952. 



Sex and Age 



1950 



Mean and Limits 

 1951 



1952 



Per cent of females 



0.412^0.017 



0.504=^0.068 



0.414 ±0.089 



Per cent of young 



0.556±0.060 



0.458^0.068 



0.480±0.090 



Per cent of females 



among young birds . . 



0.436=^=0.079 



0.515±0.144 



0.393 ±0.125 



Per cent of females 



among old birds 



0.384=b0.087 



0.496^0.159 



0.439±0.121 



notably successful game bird. Yet the productivity of the greater 

 prairie chicken found in my study is similar to that found by Lee 

 (1950:476) for the lesser prairie chicken in New Mexico in 1949. 

 If further study should reveal that 50 per cent is near normal pro- 

 ductivity for the greater prairie chicken, this fact should be con- 

 sidered in its management. Under the conditions now existing in 

 Kansas, no species with such a low productivity can withstand 

 heavy hunting eaclf year. The history of prairie chickens in Kansas 

 indicates that their productivity, in view of their present limited geo- 

 graphic range, is not sufficient to provide annual moderately re- 

 stricted hunting, for in each of the decades since 1920 open seasons 

 have been held, and in each instance thereafter the population de- 

 chned to so such a low point as to necessitate the closing of the 

 hunting season for a number of years. 



[56] 



