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in 1979. They were followed in abundance by western meadowlarks, which as 

 well as Sprague's pipits, grasshopper sparrows and chestnut-collared longspurs 

 all showed a drastic decline in densities. The decline in densities of these 

 species was probably related to a need for substantial residual grass cover. 

 Here, as with other types, residual cover was reduced by the drought and cattle 

 grazing. Results of these surveys also indicated that heavy grazing would reduce 

 densities and change or reduce species composition on these areas. 



The long-billed curlew and upland sandpiper observed in this type are "special 

 interest or concern" species for Montana. Scattered silver sagebrush occurred 

 on some mesic sites in the grassland type. Where such sites are large enough 

 the breeding bird density and diversity may be similar to that of the sage- 

 grasslands. 



Badlands 



1979 ; This type had the lowest overall density with 75.9 pairs/100 ha and also 

 low diversity with only six species. Five additional species without singing 

 males were observed on the sample strip which resulted in a slightly higher 

 number of total species for this area as compared with the grassland type 

 (11 species vs. eight species). Western meadowlarks were the most abundant 

 species in this type with a density of 37.9 pairs/100 ha. Following in decreasing 

 order were lark sparrows (19.3 pairs/100 ha) and rock wrens (10 pairs/100 ha). 



1980 ; Breeding bird densities declined 37% to 47.4 pairs/100 ha although the 

 same six species of the previous year were present. Densities of all species 

 declined or stayed approximately the same. Once again, the drought was believed 

 to be the major factor in the decline. It was interesting to note that the 

 diversity remained the same which suggested that the species found here are well 

 adapted to the extremely dry conditions which typically occur in badland areas. 

 In addition, the effects of the drought on vegetative structure probably was 

 not as great as on areas more accessible to heavy livestock pressure. 



Of the species observed in this type, two in particular were confined to the 

 badlands vegetation type. Rock wrens and Say's pheobe were commonly found 

 around sandstone outcrops and more rugged areas in the badlands. Overall, a 

 general lack of vegetation in badlands areas is one plausible explanation for 

 the low breeding bird densities and diversities observed. 



C reek 



1979 ; Of the four types sampled, the creek type contained the highest diversity 

 with a total of 14 species. Density was moderate with an average of 113.4 pairs/ 

 100 ha. In addition, nine other species without singing males were observed on 

 the strip. Again, western meadowlarks were the most common species with a den- 

 sity of 51.5 pairs/100 ha. This figure was second only to that found for meadow- 

 larks in the sage-grassland type (52.2 pairs/100 ha). Meadowlarks were followed 

 by killdeer and western kingbirds with densities of 23.6 pairs/100 ha and 7.2 pairs/ 

 100 ha, respectively. 



1980 ; This type had both the highest density (106.1 pairs/100 ha) and diversity 

 (16 species) of the major vegetation types surveyed in 1980, and showed the smallest 

 decline (6%) from the previous year. As in 1979, an additional nine species 



