a common problem in converting science to management; the 

 overapplication of findings from one area or species to 

 others . 



Management Concepts 



The implications of our findings to management are 

 dissimilar to those usually encountered. Therefore, we 

 believe it is necessary to first discuss some common 

 management concepts in relation to our findings before making 

 recommendations . 



Management of ungulates has usually centered around the 

 concept of a forage based "carrying capacity" (K) . Because 

 much of the observable natural mortality occurred during 

 winter, it has further been assumed that there was a winter 

 "bottleneck" and that the quantity and quality of winter 

 forage was a key factor determining "carrying capacity" . 

 Thus, "carrying capacity" and population dynamics in deer have 

 most commonly been interpreted to directly relate to the 

 quantity and utilization of winter forage, especially "key" 

 browse plants . 



Additionally, deer populations have been assumed to be 

 inherently irruptive, which led to "over-utilization" of 

 forage and a reduction in "carrying capacity". Management 

 strategies emphasized the importance of hunter harvests to 

 bring deer numbers into " balance " or " equilibrium " with forage 

 supplies (especially winter forage) and prevent overuse of 

 browse plants. Similarly, it has been believed that 

 populations held somewhat below "forage carrying capacity" 

 were the most productive and would yield maximum sustained 

 harvests . A reduction of the number of deer on "over-used" 

 range would reduce browsing pressure and result in improved 

 forage condition and production, thereby improving fawn 

 production and survival for the remaining deer. Thus, hunter 

 harvests were deemed to be compensated for by increased 

 reproduction ( compensatory reproduction ) and decreased 

 mortality ( compensatory mortality ) among survivors. Because 

 deer were considered to be inherently irruptive, both hunter 

 harvests and kills by predators were considered to substitute 

 for ( not add to ) mortality of the " doomed surplus " from 

 starvation or other causes. 



For our study area and mule deer population, forage 

 production and condition were primarily determined by factors 

 other than deer browsing pressure (Chapters 3 and 10). Forage 

 production and quality were determined mainly by variation of 

 temperature and precipitation. Deer browsing pressure did not 

 result in long-term deterioration of forage plants and in many 

 cases actually stimulated increased production of browse 

 plants (Mackie 1973b, Peek et al . 1978). Measures of "forage 



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