Migratory Linkages of Burrowing Owls on DoD Installations and Adjacent Lands

摘要

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 and declines in populations of colonial burrowing mammals are thought to have contributed to these declines. The reduction of prairie in the United States is linked to decreasing Burrowing Owl populations, and fragmentation of nesting habitat may result in a decreased likelihood that unpaired owls will find mates (Sheffield 1997). However, the control of burrowing mammals such as prairie dogs (Cynomys spp.) and ground squirrels (Spermophilus spp.) is thought to be the primary cause for the decline in Burrowing Owls (Desmond et al. 2000, Klute et al. 2003). 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). Burrowing Owls are also state endangered in Minnesota and Iowa, and are being considered or have been petitioned for state listing in California and Washington. Populations are thought to have declined in other states as well: Arizona, Colorado, Kansas, Nebraska, Nevada, New Mexico, and Utah (Klute et al. 2003). Hence, Burrowing Owls are listed as a high priority species in state Partners-in-Flight conservation plans. For example, the Partners-In-Flight plan for Arizona ranks Burrowing Owls 19th in conservation priority out of 177 terrestrial bird species wintering in the state. Similarly, Burrowing Owls are listed as a high responsibility species in the New Mexico Partners-in-Flight plan.