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