and general impressions about population size relative to 

 prior and subsequent full-coverage surveys. Sex and age 

 classifications on the NCRCA and adjacent areas were available 

 for many of these years, including 1968 when no data were 

 obtained on our study area. Harvest statistics, available for 

 the hunting district which included our study area, provided 

 information on relative hunting losses. Additionally, Mackie 

 monitored harvests on the study area during 1960-1965. 



Because population estimates for 1960 through 1975 were 

 more dependent on modeling, they may be less accurate than 

 estimates for 1976-1987. Considering all evidence, however, 

 they must be close to actual population levels. For example, 

 one question might relate to estimates from 1966 through 1969, 

 when neither census nor complete classification surveys were 

 conducted. Complete surveys earlier (1964 and 1965) and later 

 (1970 and 1971) provided reasonably accurate population 

 estimates and a measure of trend through intervening years. 

 Data from the incomplete helicopter survey in early winter 



1966 indicated little change in population size from the 725 

 estimated for 1965, whereas data from the partial survey in 



1967 indicated an increase that year. Also, fawn survival was 

 much better during 1967 than 1966 and harvest questionnaires 

 revealed that hunting loss was lower. Fawn: doe ratios 

 obtained for mule deer in adjacent areas north of the Missouri 

 River in 1968 indicated continuing high fawn survival and a 

 further increase in population size through early winter that 

 year. Some mortality likely occurred during the relatively 

 severe winter of 1968-69. However, the population must have 

 continued to increase through early winter 1969, when fawn 

 production and survival remained quite high, if the estimated 

 number of about 1,290 was to be reached in early winter 1970. 

 Arithmetic modeling, given available data on fawn survival to 

 December, relative levels of hunting mortality reported by 

 questionnaire, and weather patterns, indicated a relatively 

 narrow range of possible population levels for the four years. 

 Although actual populations for each of the 3 periods for 

 which estimates were made each year could have deviated from 

 our estimates (Appendix Table A), the deviation would not have 

 been sufficient to influence major conclusions concerning 

 population dynamics. 



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