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(burrow mounds and open areas between) and all nearby structures that may provide perches <br />(e.g., fences, utility poles, etc.) <br />For prairie dog towns that can not be entirely viewed from a single location because of terrain or <br />size, enough survey points should be established to provide unobstructed views of the entire <br />prairie dog town and nearby structures that may provide perches. Survey locations should be <br />separated by approximately 800 meters (1/2 mile), or as necessary to provide adequate visual <br />coverage of the entire prairie dog town. <br />Number of surveys to condom <br />Detection of burrowing owls can be highly variable and multiple visits to each site should be <br />conducted to maximize the likelihood of detecting owls if they are present. At least three surveys <br />should be conducted at each survey point. Surveys should be separated by approximately one <br />week. <br />Conducting the survey <br />• Weather Considerations Because poor weather conditions may impact the ability to detect <br />burrowing owls, surveys should only be conducted on days with little or no wind and no <br />precipitation. <br />• Passive surveyl Most burrowing owls are detected visually. At each survey location, the <br />observer should visually scan the area to detect any owls that are present. Some <br />burrowing owls may be detected by their call, so observers should also listen for burrowing <br />owis while conducting the survey. <br />Burrowing owls are frequently detected soon after initiating a survey (Conway and <br />Simon 2003). However, some burrowing owls may not be detected Immediately <br />because they are inconspicuous, are inside of burrows, or are not present on the site <br />when the survey is initiated. We recommend that surveys be conducted for 10 minutes <br />at each survey location. <br />dad- broadcast surveys To increase the likelihood of detecting burrowing owls, if present, <br />we recommend incorporating call- broadcast methods into burrowing owl surveys. Conway <br />and Simon (2003) detected 22% more burrowing owls at point -count locations by <br />broadcasting the primary male (coo -coo) and alarm (qukk- quick - quick) calls during <br />surveys. Although call- broadcast may increase the probability of detecting burrowing owls, <br />most owls will still be detected visually. <br />We recommend the following 10- minute timeline for incorporating call- broadcast methods <br />(Conway and Simon 2003, C. Conway pers. commun.). The observer should scan the area <br />for burrowing owls during the entire survey period. <br />0 3 minutes of silence <br />0 30 seconds call- broadcast of primary call (coo -coo) <br />0 30 seconds silence <br />0 30 seconds call- broadcast of primary call (coo -coo) <br />0 30 seconds silence <br />a 30 seconds call- broadcast of alarm call (quick - quick - quick) <br />0 30 seconds silence <br />0 4 minutes of silence <br />Attachment 2.05.6(2) -2 -4 <br />