method can be readily understood by persons who are not trained as life scientists. 

 Moreover, application to a given tract can be entirely quantified and objective. 



PATREC contains just two parts. One is a questionnaire usually consisting of 

 about 10 questions (Figure 2). Each question pertains to a particular environmental 

 condition — whether it occurs on the tract, and within what range of amounts. The 

 questions are based on the environmental conditions that exist where the animal 

 occurs in very high densities and where it occurs in very low densities. The ranges of 



PATREC Model for Northwest Colorado/Northeast Utah 



Sage Grouse 

 Habitat Evaluation Model 



Population Density Standards: High " 50/sq. ml.; Low - 1/sq. ml. 

 Prior Probabilities: High - .30; Low - .70 



1. What is the size of the continuous sagebrush community? 



High Low 



a. <1G00 acres .15 .25 



b. 1000-5000 acres .35 .l^5 



* c. >5000 acres .50 .30 

 d. No data 



2. What percent of the sagebrush community Is interspersed with meadows, 

 riparian zones or irrigated farm lands? 



High Low 



a. <5Z .20 .25 



b. 5-157. .25 .25 



* c. 15-30X .30 .20 



d. >30% .25 .30 



e. No data 



3. What is the average distance to open, permanent water? 



High Low 



* a. <2 miles .50 .35 



b. 2-4 miles .30 .35 



c. >A miles .20 .30 



d. No data 



A. What percent of the sagebrush community has a slope less than 10 percent^ 



a. <30Z 



b. 30-60Z 



* c. >60Z 

 d. No data 



5. What is the distance to a known strutting ground? 



High Low 



* a. <2 miles .50 .15 



b. 2-6 miles .35 .AO 



c. >6 miles .15 .45 



d. No data 



6. What is the percent canopy cover within the sagebrush community? 



High Low 

 a. <10Z .10 .30 



* b. 10-40% .70 .30 



c. >40% .20 .40 



d. No data 



2 Oct 79 CCWRU 



Figure 2. PATREC Model for Northwest Colorado/Northeast Utah - Sage 

 Grouse habitat evaluation model. 



177 



