The burrowing owl is a small, ground-dwelling raptor of arid, open habitats. Though adaptable to some landscape change, the burrowing owl is declining in many parts of its range in western North America due to habitat loss and control of burrowing mammals. It is a species of management concern in many U.S. states and is listed as threatened in Colorado.

This charismatic icon of the prairie is abundant at the Rocky Mountain Arsenal NWR where it finds suitable habitat among the Refuge’s many prairie dog colonies. Refuge biologists monitor burrowing owl nest success and reproduction each year but in 2005 efforts involved additional study. In cooperation with USGS Ft. Collins Science Center and USGS National Wildlife Health Center, we monitored burrowing owls as part of an ongoing study to evaluate the potential long-term impacts of West Nile Virus (WNV) on wild raptor populations along the Colorado Front Range. The study was conducted from April through July and included nest searches, trapping to band owls and collect samples for WNV testing, and nest observations to estimate the number of young fledged at each nest. This study will provide biologists with information on the level of occurrence and potential impacts on reproductive success of WNV on burrowing owls.

Additionally, we collected burrowing owl feathers as part of a collaborative effort to understand burrowing owl migratory linkages. The project includes burrowing owl researchers throughout the southwestern U.S. and the goal is to use stable isotope ratios in feathers to identify the wintering locations of burrowing owls and determine the amount of exchange among populations throughout the region. This information will help biologists and managers understand movement dynamics among burrowing owl populations which will help in developing informed conservation measures for declining populations.

Last Updated: 9/17/08