Reproductive success and survival of Burrowing Owls at Casa Grande Ruins National Monument and surrounding agricultural areas

Burrowing owls (Athene cunicularia hypugaea) were once a common and conspicuous breeder in grasslands and deserts throughout the western United States. However, populations of western burrowing owls appear to have declined in many portions of their range. In Arizona, only small populations of burrowing owls persist in desert, agricultural, and urban environments. Casa Grande Ruins National Monument (CGRNM), located in Coolidge, Arizona, supports a small population of burrowing owls in the relatively undisturbed desert vegetation of the Monument. Burrowing owls are also found in agricultural areas surrounding CGRNM, but we know little about the status of this population and how it interacts with the population at the Monument. burrowing owls at CGRNM, we need to know more about the ecology and conservation needs of burrowing owls both in the Monument and in adjacent agricultural areas. In this project, we are locating all nesting burrowing owls at CGRNM and within 30 miles of the Monument to help determine the size and demographic viability of the burrowing owl population in the region. We will compare reproductive success (e.g., nesting success, number of fledglings per nesting attempt), territory fidelity, and natal recruitment between burrowing owls nesting in CGRNM and surrounding agricultural areas. We will also determine the amount of movement (breeding and natal dispersal) that occurs between these two areas.