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5. The lack of any positive evidence for SJKF presence in them Hospital Creek Canyon area makes the possibility of regular '; movements by this species through the project site unlikely. ii 6. A possibility does exist for infrequent SJKF movement from " _ points outside of the Hospital Creek Canyon east or west along this drainage pathway on the project site. - B. Swainson's Hawk Swainson's hawk is a buteo or soaring-type hawk which migrates to ,. the San Joaquin Valley each April from its wintering grounds in , i South America to nest and raise its young. The preferred nesting ., site is in large riparian trees near or adjacent to good rodent " foraging areas. Because of the near total conversion of the " Central Valley to agriculture, the latter now consists of acreage ' planted to crops which promote large rodent populations. By far :; the most important of these is alfalfa. It is highly nutritious „ to agricultural rodent species such as the California . meadow. � t mouse and the Botta's pocket gopher, and alfalfa's longevity (3-5 years) permits the development of large populations of such prey. ` No Swainson's hawks were seen on the project site during the ' entire survey period. During that same time a far more commonr species, the red-tailed hawk, was observed soaring high above the . stock pond site on the western edge of 'the property. This : species was also seen on three occasions roosting in a dead tree next to the pond. Apparently the small ground squirrel population at this site was the sole prey attraction. Because the Swainson's hawk is a migratory species, the question , may be raised as to whether all specimens had left this area: before the time of the mid to late August survey period. However, observations made along my daily route to the project site confirmed this hawk's presence in the Manteca/Tracy area through September 1, 1994. This route passed by the large valley ' r riparian woodland along the San Joaquin River about 10 miles ., north of the project site. On six occasions I observed: individual Swainson's hawks either perching in large trees or foraging over alfalfa fields adjacent to to the riparian woodland, thus indicating the southern migration was not as yet„ under way. i' 4SUMMARY OF FINDINGS: SWAINSON'S HAWK SURVEY 1. With the exception the small ground squirrel colonies in the greater stock pond area and along the I-5/project site frontage, this area does not support any significant diurnal rodent population and therefore cannot effectively serve as a feeding habitat for buteo type hawks. 2. The lack of any large, riparian woodland trees on the project site proper negates the possibility that a Swainson's hawk may f nest or roost on this property. 3 . Although the project site is located slightly less than 10;- miles from several recorded Swainson's hawk nesting sites along, 13