the call playback technique (Fuller and Mosher 1981) from vehicles, 

 snowmobiles, and skis along selected survey routes between February 

 21 and March 27, 1991. Survey routes were primarily at elevations 

 higher than 5000 ft. and in areas with large patches of old growth 

 forests (Figure 3) . Routes were selected and prioritized based upon 

 conversations with Forest Service Biologist Don Sasse. 



Surveys were started one half hour after sunset and lasted 

 approximately 4 to 5 hrs, weather permitting. Playback stations 

 were one half to 1 mile apart along the survey route. The spacing 

 varied widely on some- routes due to the topographic and/or habitat 

 variation. Some survey routes were completed in their entirety on 

 a single night, others were completed in segments surveyed on 

 different nights. Therefore some segments of survey routes 

 overlapped and were surveyed more than once, other portions only 

 once. Time and estimated wind speed and direction were recorded at 

 each calling station. Temperature was recorded at the first and 

 last calling station each night. Elevation of each calling station 

 was determined from topographic maps. At each station we listened 

 for calling owls for 2 to 3 minutes, played 1 species call in all 

 4 directions for 2 to 3 minutes, listened for 2 to 3 minutes, and 

 then repeated the procedure. Boreal owl calls were played most 

 often, but occasionally great gray (Strix nebulosa ) or northern 

 saw-whet ( Aegolius acadius) calls were also used depending on 

 habitat and calling responses. Survey report forms were completed 

 for each survey conducted and owl observation forms were completed 

 for each owl heard (Appendix 1) . All calling points and owl 



