Table 7.5. Mule deer group sizes during aerial surveys in the Missouri 

 River Breaks, September 1976 through April 1984. 



a X + 952 CI 



b Means in columns followed by different letter are different, P<0.05. 



c Range of group sizes 



d Number of groups 



indicated that group size then declined through April and May 

 to annual lows during June and July. The number of females 

 per group was lowest during July (and probably late June) when 

 an average 85% of all adult females did not occur in the same 

 group with another female. Number of males per group peaked 

 during summer and early autumn, but observations of marked 

 males suggested that group size for mature males may have 

 reached another high during mid-winter through spring. For a 

 small sample of 59 observations of marked mature males during 

 mid- January through mid-May, where the entire group sex-age 

 composition was known, there were the fewest solitary mature 

 males and greatest percentage of mature males with other 

 mature males of any recorded period (Table 7.6). The smallest 

 group size for males was during the rut when 82% of males did 

 not occur in a group with other males. 



186 



