east of the banding site on October 24, 1951. Number ten was 

 not seen after banding. No banded birds were observed at boom- 

 ing grounds in the spring of 1952. 



These observations agree with the observations of flock be- 

 havior and together they indicate that different flocks share the 

 same feeding ground, but act as distinct units at other times, and 

 that the daily and seasonal ranges of flocks and individuals were 

 limited to a cruising radius of approximately one-half mile. 



These observations stand in contrast to those in Wisconsin of 

 Hamerstrom and Hamerstrom (1949) who found winter packs to 

 be made up of several smaller flocks. These packs operated as 

 units in severe weather but subdivided into smaller groups in mild 

 weather. The ranges of the various packs covered 2-4 square 

 miles and did not overlap. Schwartz (1945:83) found similar be- 

 havior in the greater prairie chicken in Missouri. There, flocks of 

 both sexes banded into packs and cruised over most of the range 

 of the separate flocks. In Nebraska, Mohler (1952:22) found the 

 home range of flocks in winter to be 2000 acres ( approximately three 

 square miles) or more. These differences in behavior of flocks 

 in wdnter may be attributed to the mild winter weather that pre- 

 vailed in the course of this study, and to the greater density of popu- 

 lation in the Welda Area. 



Activities of Males on the Booming Ground 



The activities of the greater prairie chicken on booming grounds 

 have been so completely described by Schwartz (1944 and 1945), 

 and others, that only the observed seasonal changes in activity will 

 be presented here. The earliest autumnal activity on a booming 

 ground was observed three and one-half miles southwest of Ottawa, 

 Franklin County, on September 15, 1949, where 24 males assembled 

 in the morning, engaged in territorial disputes, and unsuccessfully 

 attempted to boom. At the time of the first visit to the Welda Area, 

 on November 8, 1949, approximately 100 males were at B-1 and 

 territorial disputes and booming were in full progress. Attendance 

 at booming grounds was noted at the time of each morning visit 

 by the observer that autumn and vdnter (1949-1950), and in the 

 next autumn and winter (1950-1951). Schwartz (1945:58) found 

 that the greater prairie chicken in Missouri did not visit booming 

 grounds in mid-winter. 



Hamerstrom (1939:108) concluded that activity on booming 

 grounds was determined by upper and lower limits of a combina- 

 tion of light and temperature. This conclusion explains the mid- 

 winter booming-ground activity observed by me in 1949-1950 and 



[22] 



