carrying capacity" varied many-fold among years independently 

 of deer density; forage quantity was not limiting during any 

 year or season. Variation in forage quality (nutritional 

 content) among years and the length of time nutritionally 

 adequate forage was available in any year was of major 

 importance to mule deer population dynamics. Because quality 

 of winter forage was typically only of maintenance or lower 

 quality, we determined that forage conditions during spring 

 through autumn were of vital importance. The overall physical 

 condition of deer and amount of fat that they carried into 

 winter comprised a major component of "winter range". Length 

 and severity of winter were important as they influenced the 

 rate of use of fat reserves and the length of time deer were 

 forced to subsist on maintenance or sub-maintenance quality 

 forage . 



Although the length of time that high quality forage was 

 available had major influence on population dynamics, there 

 was no evidence that intraspecif ic competition for food played 

 a major role in determining nutritional plane of deer. Thus, 

 management concepts tied to intraspecif ic density-dependent 

 competition for food, finite carrying capacity, and "winter 

 bottlenecks" had little applicability to this population. As 

 evidenced by the combination of a variety of literature cited 

 throughout this report (Chapters 1, 3, 5, 10-12), similar 

 conclusions may also be drawn for some other areas and 

 populations . 



Because intraspecif ic competition for food was not a 

 major influence on population dynamics, the concepts of 

 compensatory reproduction and mortality also are questionable, 

 at least for this population. We were, in fact, unable to 

 measure significant compensation. When nutritional 

 deficiencies are primarily independent of the number of deer 

 on the area (density), reductions in the number of deer do not 

 improve nutritional conditions. It follows that, if 

 nutritional conditions are not improved, reproduction and 

 survival do not improve and there is little or no 

 "compensatory" (increased) reproduction or "compensatory" 

 (decreased) mortality among surviving deer. 



An additional and separate aspect of the issue of 

 compensation is the question of whether hunting mortality 

 substitutes for or is additive to other forms of mortality. 

 This is the "compensation" typically referred to across all 

 wildlife species. For example, game birds are rarely, if 

 ever, considered to destroy their food base, yet most of their 

 mortality by hunting is considered "compensatory mortality" in 

 the sense that it generally substitutes for other mortality. 

 To keep this form of compensation separated (as it should be) 

 from that addressed in the previous paragraph, we will use the 

 term substitution . Thus, we frame the question: does hunting 



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