Standardized Monitoring Strategies for Burrowing Owls on DoD Installations
ARIZONA UNIV TUCSON
Pagination or Media Count:
Burrowing Owls Athene cunicularia were once a common breeder in grasslands and deserts throughout the western U.S. and Canada. However, some populations have declined and Burrowing Owls have been extirpated from areas on the western, northern, and eastern periphery of their breeding range. Habitat loss and fragmentation due to agricultural or urban development, the reduction of prairie in the United States, and the control of burrowing mammals such as prairie dogs Cynomys spp. and ground squirrels Spermophilus spp. are thought to be the causes for the decline in Burrowing Owls Desmond and others 2000 Klute and others 2003 Sheffield 1997. Due to concerns about persistence of remaining Burrowing Owl populations, Burrowing Owls are now federally endangered in Canada, and are listed as a Species of National Conservation Concern in the U.S. US Fish and Wildlife Service 2002. Despite the declines in some portions of their range, Burrowing Owls appear to be increasing in other areas. One possible explanation for this paradox is that Burrowing Owls are becoming less migratory owls which once migrated to northern breeding locations during the summer are becoming year-round residents in the southwestern U.S. and northern Mexico. In other words, breeding owl populations might be redistributing rather than declining. If this hypothesis is correct, it has implications for the validity of current or future Burrowing Owl listing petitions and implications for the effectiveness of different conservation and management efforts. Burrowing Owls have been reported on many DoD installations in the southwestern U.S., and therefore the DoD may play a key role in the maintenance or recovery of Burrowing Owl populations if declines continue. However, we currently lack information on the extent to which Burrowing Owl populations on DoD installations are self-contained and how much dispersal occurs among locations.