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J.E. Stover 8 Associates, Inc
<br />• January 19, 2007
<br />Page 5
<br />Kit fox
<br />The kit fox has been on Colorado's endangered species list since 1998. In Colorado, kit fox have
<br />been documented recently in the lower Gunnison and Colorado River drainages in Mesa, Delta,
<br />and east Montrose counties at elevations below about 6,000 feet.l6 Historically, kit fox may have
<br />occupied suitable habitat in Garfield, west Montrose, San Miguel, Dolores, and Montezuma
<br />counties.t6''0 The Uncompahgre Valley in Delta and Montrose counties has been a center of relative
<br />abundance in the state, though observed kit fox densities there have been low's and the species
<br />was presumed close to extirpation in the year 2000, when the last census work was performed.10
<br />In Colorado, kit fox have been captured or observed in landscapes dominated by shadscale, mat
<br />saltbush, greasewood-saltbush, big sagebrush, sagebrush-saltbush, mixed pinyon-juniper
<br />sagebrush communities, and fringes of pinyon-juniper woodlands.76'A nocturnal species, the kit fox
<br />uses dens burrowed in the ground as year-round habitat near which it remains (usually within 3
<br />kilometels16) during the day." The kit fox diet consists mainly of black-tailed jackrabbits,l8 but it may
<br />also prey on kangaroo rats, ground-nesting birds, reptiles, and insects.79
<br />Primary threats to kit fox in Colorado are habitat loss, coyote predation, and direct and indirect
<br />effects of off-road vehicle recreation. After habitat loss and fragmentation due to residential
<br />development, primary threats are incidental take from coyote control actions; illegal trapping,
<br />poisoning, and shooting; road kills; and increased competition or predation from red fox, which
<br />appear to be moving into kit fox habitat in recent years.20 Kit fox populations may also fluctuate with
<br />environmental conditions such as drought cycles,21 and the relatively high mortality rate and the
<br />seemingly low fecundity of kit fox in Colorado could be limiting their ability to sustain their
<br />populations or expand into suitable habitat.16
<br />The direct and indirect effects of rural residential development in semi-desert shrublands, the kit
<br />fox's primary habitat, and the loss of safe dispersal corridors between sub-populations, greatly
<br />diminish the likelihood of an ecologically viable kit fox population in Colorado. The Hamilton Mine
<br />permit area lies just within the east extent of historic kit fox range in the west end of Montrose
<br />County.10 Although the lands within the Hamilton Mine boundary may contribute suitable habitat for
<br />kit fox, due to the lack of a viable kit fox population in the vicinity, and due to the lack of active
<br />mining and human activity within the permit boundary, renewal of the Hamilton Mine permit is not
<br />likely to cause measurable effects on the kit fox.
<br />i6 Fitzgerald, J. P. 1996. Status antl distribution of the kit fox (Vulpes macrotis) in western Colorado. Final Report. Colorado Division of
<br />Wildlife Project No. W-153-R-7.
<br />'~ McGrew, J. C. 1979. Vulpes macrotis. Mammalian Species 123:1-6.
<br />'s Egoscue, H. J. 1962. Ecology and life history of the kit fox in Tooele County, Utah. Ecology 43:482-497.
<br />'9 Sheltlon, J. W. 1992. Vulpes macrotis: kit fox. In Wild dogs: the natural history of the nontlomestic Canidae. San Diego: Academic
<br />Press.
<br />2O Beck, T. 2005 (Wildlife Biologist, Colorado Division of Wildlife•Retired). Pers. comm. with D. Reetler (Rare Earth Science, LLC).
<br />~' Cypher, B. L., G. D. Warrick, M. R. Often, T. P. O'Farrell, W. H. Berry, C. E. Harris, T. T. Kato, P. M. McCue, J. H. Scrivner, and B. W.
<br />Zoellick. 2000. Population dynamics of San Joaquin kit foxes at the Naval petroleum reserves in California. Wildlife Monographs 145:1-
<br />43.
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