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<br />I <br /> <br />Table 4. Summary of Impacts to wetland vegetation types and habitat units lor HEP analysis. <br /> <br />I <br /> <br /> -Habitat Units <br />Vegetation Type Acreage Beaver Yellow Warbler Elk GWH <br />Wet meadow 825 0 0 159 166 <br />Willow/cottonwood riparian'"' 41 20 14 34 0 <br />Total 866 20 14 193 186 <br /> <br />I <br /> <br />* Due to the small amount 01 cottonwood npanan ;n tile project area, it was not possible to sample the individual typa adequately. <br />However. since the cottonwood stands had 8 willow understory, it was combined wiItI the w//Jow riparian habitat for the HEP <br />anaJy$;s. <br /> <br />I <br /> <br />necessary in order to apply it to the wet meadow habitats on the project area Details on calculation <br />of habitat units for the three species models used, including modifications, are presented in Appendix <br />B. <br /> <br />t Following review of the draft mitigation plan, concern was expressed that the models used to evaluate <br />wildlife habitat values on the project and mitigation areas did not adequately quantify habitat .....a1ues <br />associated with the wet meadow .....egetation type. Therefore, a generalized model was developed by <br />BIO/'vVEST for the purpose of detennining wildlife habitat .....a1ue associated with these areas. <br />Parameters used in the model were restricted to those for which data were collected during pre.....ious <br />HEP studies on the project and mitigation areas. This model was formulated to show optimum .....a1ues <br />. when conditions were similar to pristine or lightly grazed wet meadow habitat in surrounding or similar <br />areas. For purposes of discussion this model is called the "general wetland habitat model' (GWH) and <br />is not related to any particular wildlife species. Prolonged o.....ergrazing in the Muddy Creek area has <br />effectively impacted riparian .....egetation and floodplain hydrology to the point that much of the wildlife <br />habitat on the area is in .....ery poor condition or nonexistent Extensive research on the deleterious <br />effects of overgrazing on riparian areas and associated wildlife habitat indicates that ungrazed riparian <br />t areas provide habitat for a far greater number and diversity of wildlife species than grazed areas <br />(Cooperrider et aI. 1986). Consequently, the curves developed for the GWH model are intended to <br />maximize suitability indices for herbaceous parameters at le.....els that were observed or known to occur <br />in an ungrazed wet meadow. The wet meadow habitat was categorized as being in gOOd or poor <br />condition for purposes of analysis. Parameter values for each category were based on estimates of <br />heavily grazed, moderately grazed, and lightly grazed conditions using HEP data as a baseline. The <br />. model was applied to all 825 acres of wet meadow habitat including naturally subirrigated and <br />artificially irrigated. A summary of the results using the GWH model is shown in Table 4 and details on <br />calculation of habitat units for the GWH model used, including suitability curves are presented in <br />Appendix B. <br /> <br />WETlAND HABITAT MITIGATION AREAS <br /> <br />Lower MttlQatlon Area <br /> <br />The proposed lower Muddy Creek mitigation area is comprised of approximately 865 acres, of which <br />approximately 20 acres are stream and approximately 390 acres of bottomland surrounding Muddy <br />Creek are of prime interest in mitigating wetland-associated impacts. Of the 390 acres, approximaJ:ely <br /> <br />8 <br />