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SURVEY PROTOCOL AND ACTIONS TO PROTECT NESTING BURROWING OWLS March 2007 Western Burrowing Owis (Athene cunicularia hypugaea) aze commonly found in prairie dog towns throughout Colorado. Burrowing Owls require prairie dog or other suitable borrows (e g. badger) for nesting and roosting. Borrowing Owls are rnigtatory, breeding throughout the western United States, southern Canada, and northern Mexico and wintering in the southern United States and throughout Mexico Federal and state laws prohibit the harming or killing of Borrowing Owls and the deskucrion of active nests. It is quite possible to inadvertently kill Burrowing Owls Boring prairie dog poisoning projects, removal of prairie dogs, or Boring earth moving for construction. Because Borrowing Owls often hide in borrows when alarmed, it is not practical to haze the birds away from prairie dog towns prior to prairie dog poisoningfremoval or construction activity Because of this, the Colorado Division of Wildlife recommends surveying prairie dog towns fat Borrowing Owl presence before potentially hazmful activities aze initiated. The following guidelines ate intended as advice on how determine if Bwmwing Owls aze present in a prairie dog town, and what to do if Borrowing Owls ate detected Ihese guidelines do not guazantee that Borrowing Owls will be detected if they are present However, adherence to these guidelines will greatly increase the likelihood of detecting Borrowing Owls Seasonal Tirnfng Burrowing Owls typically arrive on breeding grounds in Colorado in late Match or eazly April, with nesting beginning a few weeks later . Active nesting and fledging has been t ecorded and may be expected from late March through eat ly August. Adults and young tray remain at prairie dog towns until migrating to wintering Bounds in late summer or early autumn Surveys should be conducted dorirrg times when Borrowing Owls may be present on prairie dog towns Swveys should be conducted for any activities occorring between 15 March and 31 October No Burrowing Owls are expected to be present between 1 November and 14 March. Daily Timing Burrowing Owls are active throughout the day; however, peaks in activity in the morning and evening make these the best times for conducting swveys (Conway and Simon 2003).. Swveys should be conducted in the eazly morning (0.5 hours before sumise until 2 howl after sunrise) and eaily evening (2 hoors before sunset until 0.5 hours after sunset) Number and locations of survey points Burrowing Owls are most frequently located visually, thus obtaining a cleat view of the entire ptahie dog town is necessazy For small prairie dog towns that can be adequately viewed in [heir entirety from a single location, only one swvey point is necessary The swvey point should be selected to provide unobstructed views (with binoculars if necessazy) of the entire prairie dog town (burrow mounds and open azeas between) and all nearby shuchues that may provide perches (e g., fences, utility poles, etc.} For prairie dog towns that can not be entirely viewed from a single locafion 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.. Swvey locations should be separated by approximately 800 m (0.5 mi), or as necessary to provide adequate visual coverage of the entire prairie dog town. Number of surveys to conduct Detection of Borrowing Owls can be highly variable and multiple visits to each site should be conducted to maximize the likelihood of detecting owls if they are present At least three swveys should 6e conducted at each swvey point Swveys should be separated by approximately one week. Conducting the survey