Feeds elsewhere 
(3.0) 

Aerial 
(aes!) 
Terrestrial 

feeders 
(2.2) 
Secondary consumers Aquatic 
(2.0) feeders 
(2.1) 
Terrestrial 
feeders 
(1.2) 
Primary consumers Aquatic 
(1.0) feeders 
(1) 

feeders 



Tree canopy (2.25) 
Tree bole (2.24) 
Shrub (2.23) 
Terrestrial surface (2,22) 
Terrestrial subsurface (2.21) 
Surface of water column (2.135) 
Water column C2; Te) 
Bottom of water column (cote 
Tree canopy CMias) 
Tree bole (1.24) 
Shrub (1.23) 
Terrestrial surface (1.22) 
Terrestrial subsurface CL 21) 
Surface of water column (t.13) 
Water column fe 
Bottom of water column (cles 1-1) 
Fig. 1. Organization of food sources by strata along the y-axis of the species-habitat matrix. 
types) and wildlife species present in those cover types are 
not unmanageably large. 
We developed data sets describing the x and y coordi- 
nates of wildlife species in the climax ponderosa pine type 
in southeastern Montana and northeastern Wyoming, and 
also for six additional current vegetation types found in 
that potential natural vegetation type. Those additional 
vegetation types are sagebrush steppe (Artemisia spp.), 
upland grassland, riparian grassland, riparian shrubland, 
riparian woodland, and aspen (Populus sp.). Only the 
data for the upland grassland, sagebrush steppe, and the 
ponderosa pine type are extensively discussed in the 
present paper. Data for the other types are included in 
summary tables. A data base containing the appropriate 
numeric x and y coordinates was developed from the 
literature for each of the 275 nonfish vertebrate species 
resident and breeding in this potential vegetation type 
(Appendix III). The numeric data in the data base were 
structured into a computerized data file, which was then 
manipulated to produce the various displays and sum- 
maries given in the Results section. 
Each pair of x and y coordinates developed for a species 
in a vegetation cover type represents either a primary con- 
sumer or a secondary consumer role. The average x and y 
values (and their standard deviations) were calculated for 
the data describing the primary or secondary consumer 
role for each species in a data set. These means and stand- 
ard deviations summarize the feeding and breeding data 
for each species in that data set. Standard deviations of 0 
were listed if only a single x and y coordinate existed for 
the primary or secondary consumer role of a species. The 
means and standard deviations for the data about Steller’s 
jay (Table 1) are also listed in Fig. 3. 
Simple and portable computer programs (FORTRAN) 
were written for checking the basic data, computing the 
summary statistics, and printing various summaries. The 
