One of the goals was to maintain 25 bucks/ 100 does in the post-season 

 population. 



Background: The Northwest Slope mule deer population on the west slope of the Bridger 

 Mountains provides one of the best long term data sets in Montana for describing trends in 

 the mule deer buck segment. This population occupies rugged, heavily timbered, high 

 mountain country and represents a favorite location to hunt big bucks in the Bozeman area. 

 In the last 20 years, hunting pressure has intensified in this area. Portions of the habitat are 

 now more accessible because of logging roads and removal of forest cover. 



Significant numbers of large bucks occurred in this population in the early to mid-1970s. 

 Beginning in 1977, numbers of larger bucks began a steady decline continuing to very low 

 levels in the mid-1980s. When large bucks hit rock bottom in 1986, we estimated that buck 

 hunters would have to spend seven or eight days afield before observing a single four-point 

 buck. Twelve years earlier, when large bucks were at a peak of abundance, a hunter could 

 observe three four-point bucks in a single day. 



Results: The two-point season began in 1989 to restore the opportunity for hunters to kill 

 large mule deer bucks in HD 312. The ratio of 4 pt bucks/ 100 does increased from 2:100 to 

 7:100 during 1989-1991. Initially this appeared to be an encouraging trend. However, four 

 point ratios again declined during 1992-1994 to only slightly better than the mid-1980s at less 

 than 1 4pt buck/100 does). Since 1989 the buck:doe ratio has averaged 19:100 with only one 

 year (1992) that exceeded the goal of 25 bucks: 100 does. 



The age structure of the harvest followed a similar pattern to the buck: doe ratios. A much 

 higher percentage of older bucks (five years and older) were killed in HD 312 in 1991-1992 

 as a result of lower rates of hunter harvest during the first few years of the two-point season 

 and because of above average fawn survival. During 1993-1994 percentages of five years and 

 older bucks in the harvest declined in HD 312 to a level similar to HD 393, where the 

 population is under a consistently high level of exploitation and the bulk of the post-season 

 population consists of yearlings. 



Managing for an improvement in availability of older mule deer bucks is a challenging 

 endeavor considering the significant natural losses that occur in the male segment of 

 mountain-foothill mule deer populations. During 1990-1994, annual samples of six to eight- 

 month-old radio-collared male fawns have exhibited mortality rates of 52, 35, 39, 78, and 38 

 percent during the January - June period of those years, respectively. Cause of death was 

 predominately predation and winter malnutrition. 



Conclusion: 



1) The 2-point season has not provided a sustained improvement in post-season 

 buck: doe ratios. In only one of six years did the ratio exceed the stated goal of 25 

 bucks: 100 does. 



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