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nesting in these situations was no different than for more secluded nests (Estep 1989). Other aspects of the species breeding biology are adequately treated in the Supplemental Biotics Survey for Buckeye Ranch Development(1992). Swainson's hawk is a species of open country that forages primarily on the wing. Soaring on updrafts or relatively high coursing are common tactics utilized by the species. Swainson's hawks often "flycatch" large grasshoppers and other insects. Swainson's hawks forage in open grasslands, sparse shrublands and savanna, and seasonally dry wetlands. In the Great Valley these habitats have been dramatically lost or altered. Yet Swainson's hawks can and do utilize a variety of agricultural cover types. Schmutz (1987) found that this small buteo is more abundant in areas of moderate cultivation than either grassland or areas of extensive cultivation. Moderate amounts of cultivation provide a rich and reliable food source particularly when crop phenology is suitable for foraging (fresh mowing, disking, harvest, etc. provide an edge habitat that concentrates prey items such as rodents, insects and birds). The ability of the hawk to procure food is probably related to the interaction of crop phenology and cultural practices. Historically, natural grassfires acted to produce such an edge effect, and Swainson's hawks are regularly seen concentrating their foraging activities on burning and burned agricultural fields. Seasonal marsh habitat, of which their were nearly 4 million acres in the Valley also provide important foraging habitat for the species. Seasonally dry (mid-spring through early fall) wetlands have high bioproductivity that Swainson's hawks and other raptors readily exploit. Observations on restored seasonal wetlands on the Cosumnes Preserve confirm active foraging by Swainson's, red-tailed and red-shouldered hawks, northern harrier, white- tailed kite, prairie and peregrine falcons, American kestrel, and merlin (A. Engilis, unpubl. field notes). Estep (1989) characterized and rated agricultural cover types found in the Buckeye Ranch Resource Plan (November, 1993) 117