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intensity from different vegetation types. Indices of relative abunaance for data <br />• on predators obtained from the scent station visitation technique are provided by <br />a formula developed by the Denver Wildlife Research Center (Iinhart and <br />Icnowlton 1973) <br />Total number of visits by species <br />Index = a 1000 <br />Total number of operable station nights <br />Species Diversity Index. An index to species diversity is provided for certain <br />habitat types for certain groups of aninals. This index is based on the <br />Shanron-Weizler function from the field of information theory (~largalef 1967; <br />MacArthur afld MacArthur 1971; Lloyd and Ghelardi 1964; Pielou 1966). As a <br />diversity inF3?.x for carmunity analysis, the function describes the average <br />degree of uncertainty of predicting the species of a given individual picked at <br />random from the caimiuiity. This uncertainty and the index increase both as the <br />number of species increases and as the individuals are distributed ~nre and more <br />equitably arrong Species already present. The geJleral formula for this index is <br />as follows: <br />H = Epi loge Pi <br />where pi = decimal fraction of total individuals belonging to the ith species. <br />This index varies from values of 0 for habitats containing a single species to <br />values of 4 or 5 for conrnuru ties containing many species, each with a small <br />number of individuals. The Shannon-Weiner species diversity index may be used to <br />ccu~are o~rmunity ~sition data from a variety of sources. Difference in <br />diversity may be expected for comminities at different stages of succession, <br />in different habitats or at different rimes of the year. <br />Habitat Affinities. Most animal species depend upon their irtmediate surroundings <br />to provide basic requirements for food, shelter and water. Determination of <br />habitat affinities within the mrmal range of a species may indicate its <br />particular needs for survival and continued growth and reproduction. In general, <br />an animal's habitat may be characterized by the predominant vegetation. EVaiuation <br />of distribution abundance patterns of different animal species wit}u_n and between <br />vegetation types provides a measure of habitat affinity. <br />Zf all animal species in an area were randomly distributed with respect to <br />-14- <br />• <br />JUN f 1 11180 <br />