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� r drainage has two major tributaries when, taken together, makes it the longest of all four creek systems. In addition to these. length differences, the two long canyons are also considerably: wider than the shorter ones, especially in their terminal areas; west of I-580. Finally, the long canyons have many side canyon tributaries , many of which pass though relatively low hill;,. systems. In contrast, the Hospital Creek canyon has only a few, short, steep side canyons. Indeed, the distal third of this.: drainage is a steep-walled ravine. When applying these contrasting terrain features to SJKF distribution, one must recall that this canine evolved as a semi- . desert species which once ranged over great expanses of _flat, salt bush scrub habitat in the pristine San Joaquin Valley. With the advent of irrigation and urbanization during this century, its only remaining habitat segments are the canyon floors and; ° east lowland fringes of the Innercoast Range west of I-580 and I 5. A tabulation by Bell, 1994, of SJKF sightings for the past three decades clearly shows this present marked separation of SJKF arid grassland habitat and the irrigated cropland of San: Joaquin County (Figure 14) . However, the recent studies of these four Innercoast Range drainages in western San Joaquin County show that the current habitat preference of the SJKF for canyon floor sites is not. universal. Indeed, it now appears that only those creek drainage., ' systems with comparatively broad canyon floors and long courses with extensive side canyons which permit lowland movement through segments of the Innercoast Range provide suitable permanent habitat for this canine. Conversely, smaller drainages which do not possess these features appear to be ignored by kit fox. In addition, the intense grazing pressure and past soil surface: disruption in the lower Hospital Creek drainage may make this; particular small canyon even less appealing as a SJKF habitat. One further finding common to all four of the I-580/1-5 junction. studies is that no record of any kind of SJKF presence east of 1- 580 was obtained. This is especially interesting since the I-580 : bridge overpasses for both Lone Tree and Hospital Creeks appear to afford safe and relatively secluded passage to the irrigated" orchard and cropland to the east. The fact that this semi-desert adapted species has not been found in this latter area supports. the sound ecological reasoning that this is simply not appropriate habitat for the SJKF. Given the convincing negative survey results for studies east of I-580 and equally strong evidence for the fact that the agricultural lands here do not conform to the scientifically based habitat description for this species, only one question remains: Does a SJKF ever venture under the I-580 overpasses to sites east of this highway? The best answer here, I believe, yes once in a great while. This idea is based on several past: records of male SJKFs wandering far beyond their average home] range estimate of 1.7 square miles (Zoellick, et al, 1987) . These were most likely cases of displacement of young males from an established adult male's territory, and as such must be considered a small part of this species' overall life history. 11