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moderate populations here. This in turn results in very poor foraging conditions for nocturnal rodent predator such as the barn own and the SJKF. Burrow Survey All burrows above the small rodent size range (one to two inch diameter) located during the transect walks were those of the ,, California ground squirrel. These were concentrated around the '` 1 .. stock pond and in the rubble deposits west of I-580. A smaller - number were located along the orchard/I-5 right-of-way border on the eastern edge of the site. None of these burrows were greater . than four inches in diameter at a distance 1.5 to 2 feet within ' from the entrance. This fact is significant because burrows . beyond these dimensions are considered as potential kit fox dens by the USFWS. In addition, no large burrow of any sort was ,: located on the property. Potential retreat sites for small ' mammalian carnivores do exist, however, among the various larger items in the ad hoc dump area on the project site segment west of ; I-580. These were inspected for signs of carnivore occupancy (scat, discarded prey bones and skin, etc. ) but none was found. ' Ell Significance of Present and Past 1-580/1-5 Area SJKF Surveys The negative results of this current SJKF survey are the same as the three previous such studies conducted within the past four years in the greater project site area and briefly reviewed in the background section of this report. Of particular interest . here is the 1990 EIP survey which, in addition to surveying the ! project site proper, was able to extend their work approximately: four miles southwest along the Hospital Creek drainage. Here , eight track board stations and several night spotlight searches also failed to reveal SJKF presence. This finding is in sharp contrast to the results of the same EIP , Associates survey team's study effort north of the project site in the Lone Tree Creek valley west of I-580. Here 20 track board , and photo stations produced nine records of the SJKF. In ': addition, I recorded tracks and observed one specimen of the SJKF in 1992 in a survey of the upper Lone Tree Creek drainage beyond the .western limits of the EIP survey. However, the EIP Associates, 1991, report of a six track board , survey effort along the Deep Gulch drainage north of Lone Tree ' Creek mirrored their negative results obtained on the Hospital Creek canyon. Yet still further north in the eastern Corral. Hollow Canyon area, surveys by both this firm and graduate students from California State University, Hayward, obtained photographic records of SJKF presence. Careful consideration of all these findings strongly suggests that the SJKF prefers the habitat conditions of some creek ! drainages but not others, and this begs the ultimate question - . t A why? A close examination of USGS topographic maps of this region suggests a most interesting reason. Both the Lone Tree Creek and '; ' Corral Hollow Creek are well over twice the length of the , Hospital and Deep Gulch drainages . Indeed, the Lone Tree 6 i 10 k � ,