Douglas fir ( 33% ) . Features at vdiich a third or more of the sites 

 with that cxxnponent had moderate activity were: cleancuts (100%), 

 lakes (67%), and lodgepole pirie (36%) (Table 2). 



Of those sites that had high bat activity, 100% of them had rock 

 outcrops nearby, 100% had riparian areas nearby, 100% of them had 

 riparian areas with either Douglas fir or mature hardwoods, or 

 riparian areas with rock outcrops nearby ( Table 3 ) . Components that 

 were part of the habitat at half or more of the sites with high bat 

 activity, in addition to those mentioned, were beaver pcxids (60%), 

 mature Douglas fir (80%), and mature hardwoods (66%). No sites with 

 high bat activity had caves or lakes nearby, though a third of the 

 sites with moderate activity had caves or lakes nearby ( Table 3 ) . 



In a study of forest bats in Oregon and Washington, all species 

 except the Silver-haired bat (Lasionycterts noctivagans) in 

 Washington, were detected at dramatically higher rates in old-growth 

 stands than in young or mature stands of Douglas fir (Thomas and West 

 1991). Bats were between 2.5 and 9.8 times more abundant in old- 

 growth than in young or mature stands in both regions. Thomas and 

 West (1991) speculated that the activity of the Myotis species, the 

 Big brown bats, and the Silver-haired bats in Oregon were more 

 abundant in old-growth because that habitat provided an increased 

 variety and abundance of day roosts. 



Perkins and Cross (1988) reported that all of the Hoary bats and most 



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