20 
wildlife guilds that occur as guild blocks are added to 
wildlife habitat. 
The greatest difficulties in working with our guilding 
technique are associated with developing the data base to 
drive the guild analyses. Difficulties occur because wild- 
life species have not historically been associated with ver- 
tical strata in the environment (an important subdivision 
within the species-habitat matrix). We believe this is an 
imprecision in the quality of natural history information 
(field biologists have not historically associated species 
with strata), rather than a flaw in the design of the species- 
habitat matrix. The correct positioning of wildlife species 
within vertical strata requires expert judgment even 
though food habit and breeding niche requirements are 
among the best known information about individual 
species. A second problem encountered in building the 
data base is the determination of “normal” and “abnormal” 
food habits and breeding activities. We consider “abnor- 
mal” feeding and breeding information to be those excep- 
tions that are so unusual and occur so rarely as to be note- 
worthy events. Such noteworthy events are not considered 
in the development of the species data base. 
The suggested application of the principles determfned 
from the guilding model is presumed and not proven. The 
determination of the utility of the proposed applications 
must wait until an applications study, presently under 
way, is completed. Still we can conclude that the ability to 
associate wildlife guilds with the structure of habitat 
allows good predictions to be made about the impacts of 
habitat change on the structure of the wildlife community, 
and that wildlife guilds actually occupying an area com- 
pared with the standard guild structure that can occupy 
an area may possibly be a useful measure of habitat 
quality. This measure compares the structure of the actual 
wildlife community with the structure of the wildlife com- 
munity that would potentially occupy the area. The 
standard guild structure is determined for the climax com- 
munity of the potential natural vegetation that can occur 
on an area and the actual guilds present on the area are 
determined by comparing species found on an area with 
lists of species comprising the guilds that can occur on the 
area. An additional utility of the guilding technique is that 
the structure of the wildlife community present at some 
future time can be simulated if the structure of the vegeta- 
tion community present at the future time can be hypothe- 
sized. This capability should enhance the assessment of 
impacts of habitat change on the wildlife community. 
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