equilibrium level with reduced fluctuation has been a 

 management goal after the 1970s. Whether that goal has been 

 achieved and will be sustained can only be determined by 

 additional years of testing. 



Interpretation of trends and results and conclusions of 

 studies may often depend upon such chance events as the 

 particular year data collection starts and how long it 

 continues. For example, for our study (Fig. 13. 1G) , the 

 reader can choose a variety of 10 consecutive year periods 

 that will indicate vastly different, even opposite, population 

 trends. These could also provide vastly different 

 interpretations of population ecology and regulation. The 

 initial year of investigation makes all the difference in 10- 

 year trend. Similarly, it is obvious that 10 years does not 

 necessarily provide a long-term perspective. The degree of 

 environmental variability within an area may be a major 

 consideration in determining valid study length and 

 reliability of trend projection. 



One year's change did not make a trend, but at about the 

 time a long-term trend seemed to become obvious, the trend was 

 often about to change. This seemed to occur because extremes 

 tended to make the past trend obvious and "extremes" were 

 unlikely to occur for 2 or more years in succession. Thus, 

 population or any other measured data tend to reverse after 

 extremes . 



We suggest that trends in 1 population on 1 area provide 

 insight to dynamics only after long periods. To best or most 

 quickly measure the results of any management practice, the 

 trends of 1 "treated" and 1 "untreated" population within 

 similar environmental types should be measured simultaneously. 

 This paired population approach is necessary to determine how 

 much of the trend was "natural" and how much resulted from 

 management action. 



Habitat Evaluation and Management 



The importance of healthy, productive habitat to healthy, 

 productive animal populations has been justly recognized for 

 years. However, concurrence on the meaning of healthy habitat 

 and habitat requirements of species is lacking. This results 

 partly from the different perspectives and objectives of 

 different individuals, groups, and agencies. It is also the 

 result of the lack of solid information about and 

 understanding of the interactions between habitat and animal 

 populations despite years of various types of studies. The 

 assumption that winter habitat ("range") was of overriding 

 importance to big game populations in the northern United 

 States may have resulted in inadequate data collection on 

 other aspects of deer ecology. This led to lack of long-term 



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