S age Grouse 



Western Segment 



Distribution 



During the course of this study, 495 sage grouse were ob- 

 served. The distribution of these observations is presented in 

 Figure 19. The distribution of sage grouse in the study area is 

 directly related to the availability of sagebrush habitat. Sage 

 grouse are the most restricted in niombers and distribution of the 

 upland game birds. This species, like the antelope, has seen 

 the greatest reduction in its historic habitat with the advent 

 of dryland small grain agriculture. 



The primary habitat for this species in the study area is 

 found in the heads and divides between Birch Creek, Sand Creek 

 and Black Coulee on the north side of the Missouri River. In 

 this area, a native sagebrush-grassland vegetation type exists 

 and supports a significant population. Throughout the rest of 

 the study area, the sage grouse has been reduced to essentially 

 remnant populations where sagebrush has been left by farming 

 operations or has received a degree of protection by federal 

 ownership. However, these areas are being continually reduced 

 by land conversion programs. Reproducing populations exist on 

 the lower Teton and Marias river breaks, the Rattlesnake Coulee 

 drainage, the Missouri River Breaks near Virgelle, and the Arrow 

 Creek drainage. Sage grouse have been reported southeast of 

 Fort Benton along the Missouri Breaks. These populations, with 

 the exception of Arrow Creek, are quite limited in numbers and 

 available habitat. Habitat use data presented in 1977 showed 

 the importance of coulee and riverbottom areas of sagebrush- 

 grassland vegetation. A shift to small grain agricultural areas 

 was found in late summer and early fall. During severe winter 

 conditions these birds appear to make greater use of the steeper 

 sagebrush breaks . 



Population Characteristics 



Five sage grouse strutting grounds were located during the 

 spring of 1976 between Birch Creek and Black Coulee. Table 15 

 presents the maximum number of males observed on these grounds . 

 The average number of males observed per ground was 2 3 in 1976, 

 15 in 1977, 15 in 1978, and 17 in 1979. Counts were not recorded 

 for three grounds in 1979 due to poor conditions on the date of 

 observations . 



Brood observations for the course of the study recorded an 

 average of 5.3 young per brood in 1976, 3.8 in 1977, and 4.0 in 

 1978. The low figures of 1977 and 1978 are considered low due to 

 limited observations. 



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