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intensity from different vegetation types. Indices of relative abundance 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 (1inhart and <br />Knawlton 1973) : <br />Total number of visits by species <br />Index - X 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 animals. This index is based on the <br />Shannon- Weiner function from the field of information theory (Margalef 1967; <br />MacArthur and MacArthur 1971; Lloyd and Ghelaxdi 1964; Pielou 1966). As a <br />diversity Index for connemity analysis, the function describes the average <br />degree of uncertainty of predicting the species of a given individual picked at <br />random from.the community. This uncertainty and the index increase both as the <br />number of species increases and as the individuals are distributed more and rare <br />equitably among species already present. The general formula for this index is <br />as follows: <br />H = Ep log P <br />where p = decimal fraction of total individuals belonging to the i species. <br />This index varies from values of 0 for habitats containing a single species to <br />values of 4 or 5 for communities containing many species, each with a small <br />number of individuals. The Shannon-Weiner species diversity index may be used to <br />compare community composition data from a variety of sources. Difference in <br />diversity may be expected for communities at different stages of succession, <br />in different habitats or at different times of the year. <br />Habitat Affinities. Nbst animal species depend upon their immediate surroundings <br />to provide basic requirements for food, shelter and water. Determination of <br />habitat affinities within the normal 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. Evaluation <br />of distribution abundance patterns of different animal species within and between <br />vegetation types provides a reasure of habitat affinity. <br />If all animal species in an area were randomly distributed with respect to <br />-14- <br />JUN 1 1 i9-80 <br />