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FORAGING HABITS Swainson's hawks hunt for prey while soaring at intermediate heights or by pursuing the item on the ground(CDF&G, 1988). The most common prey items include voles,ground squirrels and grasshoppers. THREATS AND MANAGEMENT CONCERNS The Swainson's hawk breeding population has declined from an estimated 17,136 pairs at the turn of the century to approximately 550 breeding pairs in 1988 (CDF & G, 1988). Swainson's hawks are listed as a threatened species in California. This status is primarily due to significant habitat losses. Urban development and the expansion of agriculture had drastically reduced grassland habitats and Swainson's hawks now rely on pasturelands and alfalfa fields for their principal foraging habitat. The replacement of alfalfa and pastureland with incompatible agricultural uses such as rice and orchards further reduces the available foraging habitat. Lastly, the loss of existing nest sites in agricultural,woodland and riparian areas poses another major threat to Swainson's hawks in California (CDF & G, 1988; Ehrlich et al., 1988). SELECTED REFERENCES Aitkenhead,Donna I. 1986. Species of special concern. Outdoor California 4:6- 10. Beedy, Edward C. and Stephen L. Granholm. 1985. Discovering Sierra Birds. Yosemite Natural History Association and Sequoia Natural History Association. 229 pp. Bent, A.C. 1937. Life histories of North American birds of prey. Part I, Dover Publications,Inc.,New York. 409 pp. Bloom, Peter H. 1980. The status of the Swainson's hawk in California, 1979. Federal Aid in Wildlife Restoration, Project W-54-R-12, Nongame Wildl. Invest.,Job Final Report 11-8.0. 42 pp. California Department of Fish and Game. 1987. Special animals. Natural Diversity Data Base. 18 pp. Calif. Dept. of Fish and Game. 1987. Five-year status report: Swainson's hawk. Nongame Bird and Mammal Section, Wildlife Management Division. 9 pp. Calif. Dept. of Fish and Game. 1988. 1987 Annual report on the status of California's state listed threatened and endangered plants and animals. State of California, The Resources Agency, Department of Fish and Game. 109 pp. Calif. Dept. of Fish and Game. 1988. List of state and federal endangered and threatened animals of California. State of California, The Resources Agency,Department of Fish and Game. 4 pp.