DISCUSSION AND MANAGEMENT CONSIDERATIONS 



The study area supports a typical shrubsteppe bird community, with intermixing of 

 species tied closely to sagebrush and grassland Sagebrush obligate bird species present included 

 Brewer's Sparrow (the most widespread of these) and Sage Thrasher to a much lesser degree. 

 Grassland birds of highest conservation priority, such as Sprague's Pipit and Baird's Sparrow, 

 were barely represented on point counts, but may have occurred more frequently in isolated 

 patches within the study area. Neither species, however, occurs in abundance to the degree they 

 are present in pothole regions north of the Highline adjacent to the Canadian border (pers obs.) 



The breeding birds of the area were investigated previously in 1966 and 1967 (Feist 

 1968) on five 40-acre plots, prior to herbicide spraying to clear sagebrush. Brewer's Sparrow 

 and Vesper Sparrow were the two most abundant nesting species. Western Meadowlark and 

 Homed Lark also bred on all plots, with Lark Bunting and Sage Thrasher on three plots and 

 Mourning Dove on one plot. Sage Grouse were observed on one plot. 



Brewer's Sparrow was detected on 27% of the points during 1998-1999, which likely was 

 an underestimate because of the timing of many counts in 1998. Western Meadowlark, Vesper 

 Sparrow, and Lark Bunting were the three most abundant species in 1998-1999, occurring on 

 97.4%, 85.9%, and 61.2% of the point counts, respectively. Homed Larks were detected on 19% 

 of the points (Table 1), but they, too, could have been undercounted because they are an early- 

 nesting species. A striking difference between Feist's (1968) resuhs and the point count survey 

 is the relative abundance of Sage Thrashers on Feist's few study plots versus the rarity of Sage 

 Thrashers at the 1998-1999 points (Table 1): thrashers were detected at only two points on two 

 routes during the recent survey. Sage Thrashers tend to nest in taller and denser sagebmsh 

 patches (Paige and Ritter 1999). Sagebrush control in the study area that reduces larger more 

 mature patches of big sage will adversely atTect this bird species. Montana PIF (Casey 2000) 

 recommends achieving a goal where sagebmsh is at least 5 m in height with high foliage 

 density. Brewer's Sparrows are less specific in their habitat needs, and will occupy low-stature 

 sagebmsh in areas with relatively low canopy cover (averaging 13%, but ranging from 6-33% in 

 one Montana study [Bock and Bock 1987]) Both species will avoid areas recently burned or 

 otherwise denuded of sagebmsh. 



The study area continues to support a large population of Brewer's Sparrows. Protection 

 of some plots that allow continued growth of patches of sagebmsh will also make them attractive 

 to Sage Thrashers. However, densities of this species tend to be relatively low (30 individuals 

 per km , or 78 per mi ) even in extensive areas of sagebmsh with the preferred stmcture and 

 density (Paige and Ritter 1999). Montana PIF (Casey 2000) recommends a long-term goal of 

 maintaining at least 50% of existing sagebmsh stands 30 years of age or older. However, this 

 goal is not just for a static set of sites but should include the continued presence of a diverse 

 habitat stmcture by maintaining variation in the grass understory. Grazing can be used as a tool 

 to achieve and maintain this dynamic mosaic. 



A number of specific recommendations pertinent to maintaining the viability of the 

 shmbsteppe and grassland habitats in the study area, and their associated breeding bird faunas, 

 are presented in detail in Paige and Ritter (1999) and the Montana PIF draft conservation plan 

 (Casey 2000) It is recommended here that 1 ) the routes established in 1998-1999 be mn in 

 alternate years (maybe 50% of the routes each year) for at least five years to establish trends in 

 the area, and 2) Feist's (1968) plots be resampled annually. 



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