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OUR Potentially suitable habitat for burrowing owls at the Site consists of a large abandoned gravel pit containing annual grassland over generally hilly terrain(see photograph# 1). Property surrounding the Site is currently or has been used in the past for commercial surface mining operations. Vegetation cover at the Site consists primarily of non-native annual grasses.Non-native invasive species common at the Site include tree tobacco (Nicotiana glauca), Russian thistle (Salsola tragus), yellow star thistle (Centaurea solstitialis), turkey mullen (Eremoearpus setigerus), tar weed (Hemizonia spp.), and a variety of non-native grass species (i.e. Bromus spp., Hordeum spp.). Native herbaceous plants observed include sticky gumweed (Grindelia spp.), lupine (Lupine spp.) and telegraph weed (Heterotheca gr°andiflora). An irrigation canal located immediately adjacent to the eastern boundary of the site serves as a potential water source for burrowing owls. The canal contained flowing water at the time of the survey, but transmits fluctuating levels of water throughout the year. A shallow abandoned quarry immediately south of the Site contains hydrophytic vegetation (willow trees, cottonwood trees) indicating the presence of water, although the quarry was dry at the time of the survey (see photograph#2). California ground squirrels (Spermophilus beecheyi) and their burrows are found in various locations at the Site. In particular, the deep ravine that runs diagonally through the center of the Site (see photograph # 3) and the base of the eastern quarry wall contain the highest concentration of both ground squirrels and their burrows. Other more isolated burrow systems were also found throughout the Site. Potential prey species for burrowing owls on the Site include small mammals, insects, birds, and reptiles (see Table I for a complete list of observed wildlife species). The Site appeared to provide an adequate prey base for burrowing owls based upon observations in the field. Burrowing Owl Species Profile The burrowing owl is a mottled brownish and sand colored, dove sized raptor, with large yellow eyes, a rounded head lacking ear tufts,white eyebrows, and long legs compared to other owl species. It is a ground dwelling owl typically found in arid prairies, fields, and open areas where vegetation is sparse and low to the ground. The burrowing owl is heavily dependent upon the presence of mammal burrows (commonly ground squirrel and American badger) in its habitat to provide shelter from predators, inclement weather, and to provide a nesting place. Burrowing owls spend a great deal of time standing at the entrance to a burrow or perched on a fence post or other low vantage point from which they hunt for prey. Burrowing owls occasionally hunt by hovering in mid-air and descending upon their prey from above; a hunting strategy commonly used by the American kestrel (Falco sparverious). Burrowing owls feed primarily on insects such as grasshoppers, June beetles, and moths, but will also take small rodents, birds, and reptiles. They are active during the day and night, but are considered a crepuscular owl, generally observed in the early morning hours or at twilight. The breeding season for the burrowing owl is February I through August 31. Up to eleven, but typically seven to nine eggs are laid in a burrow, abandoned pipe, or other subterranean hollow where incubation is complete in 28-30 days. Young burrowing owls fledge Burrowing Owl Survey Rpt(draft3):L 2