Laserfiche WebLink
C <br />the type as determined by Chi - square data (Appendix B, Part 1). <br />The deer mouse was the only species captured in the other two vegetation <br />types sampled, upland sagebrush and .grassland pasture.. As a result, the species <br />diversity index was 0.0 for both types. Relative abundance indices was <br />also low for both types with 0.8 .individuals /100 trap nights for upland <br />sagebrush and 0.4 individuals /100 trap nights for grassland pasture. <br />As a result of the low number of captures, the deer mouse did not reveal an <br />affinity for any type sampled. <br />Assuming that trapping results reflect actual relative abundance of small <br />mammals in each of the types sampled, it is evident that both upland sage- <br />brush and grassland pasture do not provide good small rnanmal habitat at <br />the Mole site. Predation, competition with Gunnison's prairie dogs (see <br />. below) , lack of appropriate food and /or nesting requirements, and the homogene- <br />ity of the types (reduced number of small mammal niches) are all possible <br />reasons for the low populations levels observed on these two types. Con- <br />versely, the riparian type provides habitat for two small mammal species with <br />narrow habitat requirements, the western harvest mouse and meadow vole. <br />Both are generally found in riparian situations only (Leichleitner 1969). <br />Moreover, the riparian type, in the form of an increased vegetation cover, <br />r esul €sin both more species and a higher population level i, this habitat. . <br />Small Mammal Species. The deer mouse was captured in all vegetation types <br />sampled in the study area. This nocturnal species is probably the most <br />abundant and widespread mammal in Colorado (Lechleitner 1969). The deer <br />mouse occurs in a variety of habitats, from deserts to marshes and from prai- <br />ries to above timberline. A total of 4 deer mice were captured, representing <br />a total relative abundance over all types of 0.7 individuals /100 trap nights. <br />The deeranuae did not show an affinity for a particular habitat type. The <br />sex ratio of a1l deer mice captured was 0.75 females and 0.25 males. <br />ftedow vole habitat includes moist areas with abundant supplies of grasses, <br />sedges or other green, succulent vegetation.. The only habitat with these <br />characteristics in the study area is riparian and was the only habitat in <br />-29- <br />JUN 1 1 1480 <br />