That relationship occurred independently of deer density. It 

 may still be argued that we overlook the importance of forage 

 quantity because during some years deer face a shortage in the 

 quantity of quality forage. We do not deny that argument has 

 merit; the point remains however, that we found no evidence 

 that quantity or quality of forage available was adversely 

 impacted by deer, either by measurement of the vegetation or 

 by detecting density-dependent relationships for fawn 

 production and mortality. 



Generally, the growing season on our study area was 

 short, with most herbaceous plants maturing by late July in 

 most years. Because there was little elevational gradient on 

 the area, forage desiccated rapidly on all areas when severe 

 drought occurred; plants on north- and east-facing slopes 

 remained green only a few weeks longer than those on other 

 sites. Also, north- and east-facing slopes (the Douglas fir 

 and Pine-Juniper-Fir types) comprised only 15.7% of the study 

 area. Thus, even if plants/forage on those areas remained 

 green much longer than plants on other areas, only a portion 

 of all deer, which remained widely dispersed on the study 

 area, could take advantage of them. Certainly, deer that 

 occupied home ranges including those types faced better living 

 conditions during all years, but parturition territoriality 

 functioned to limit the number of deer that live in such 

 habitats during summer and early autumn when availability of 

 green, high quality forage was critical. 



Conditions that led to a reduction in the quantity of 

 quality forage were not related to deer numbers or to 

 "overbrowsing" or "overgrazing" by deer; thus, a reduction of 

 the number of deer in areas where forage was of poor quality 

 would not increase the survival of other deer in that area. 

 Forage quantity and quality on this area were determined 

 primarily by annual variations in precipitation and 

 temperature. How individual deer fared under the varying 

 annual conditions depended, at least in part, upon where they 

 lived, the topography, vegetation, weather /climate, and other 

 land use within that area. 



Contributions of the Fixed-Stable Habitat Base to Population 

 Dynamics . 



The deer-forage relationships just discussed are only one 

 aspect of population-habitat relationships . Much of the 

 important deer-forage relationship was part of the dynamic- 

 variable habitat component of our model (Fig. 1.4). However, 

 fixed-stable properties of the habitat model such as 

 topography and habitat structure interacting with the variable 

 habitat components and the morphology, physiology, and 

 behavior of the deer (animal component, Fig. 1.4) also played 

 a major role in population ecology and dynamics. 



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