COMPLIANCE INFO_1991-2006 - Laserfiche WebLink

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agricultural lands within the primary urban area, as defined by the City of Manteca General Plan, are under Williamson Act land conservation contracts. One principal factor limiting agriculture in the planning area is the availability of productive soils. As urbanization encroaches on farm lands , productive soils are permanently removed from agricultural use. Runoff from all soils in the planning area is slow, and the hazard of water erosion is slight. Soil permeability in the planning area ranges from slow to rapid, and the hazard of wind erosion changes from slight to high. The value of agricultural habitat to wildlife depends on several factors , such as the type of crop, irrigation systems, pesticide use, farming practices , and the surrounding land use. In late summer , flooding of fields attracts migratory birds. During fall and winter, agricultural fields are important habitat for shore birds and large flocks of geese, swans, and ducks. Most open fields may receive some waterfowl use, but cornfield stubble , fallow fields , and bare, plowed fields are most consistently valuable to wintering birds. Winter food is supplied by unharvested grain, weed seeds, young sprouts, insects , worms , and grubs in the field. Greater white-fronted geese , snow geese, and Ross' geese depend on cornfields for wintering grounds. Suitable wintering habitat is a critical limiting factor for many Pacific Flyway waterfowl populations. The Central Valley is habitat for roughly 60 percent of all Pacific Flyway waterfowl and for 91 percent of all waterfowl wintering in California. Pastureland that is not cultivated or mowed provides a relatively stable habitat, permitting year-round use; it also provides abundant cover and insect and plant foods. North of the planning area, sandhill cranes are known to prefer this habitat for roosting and may possibly occur near Manteca as well. Unflooded fields and pastureland provide habitat for the three most important game birds in the Delta: the native California quail , the mourning dove, and the introduced ring-necked pheasant. The abundance of these birds on agricultural lands is increased by the proximity to riparian vegetation. Orchards and vineyards are used by songbirds as feeding and nesting habitat , particularly during the spring and summer. Insecticide or herbicide application during times of heavy bird use may reduce the available food source and limit the habitat value. Birds of prey hunt over all of the above habitats in agricultural lands. Common birds of prey found in the project area are black-shouldered kites , red-tailed hawks, and American kestrels. No cultural resources (archaeological, paleontological, historic , ethnographic) have found to be present on the facilities or disposal/irrigation site nearby. 5