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0009n3 The guilding approach, though it is theoretically more appropriate for modeling than the single-species approach, should be evaluated in the context of the overall PHABSIM process. The effect of including additional characteristic species (such as invertebrates) should also be evaluated. More work must be conducted to address special habitat types (e.g., sloughs, backwaters, etc.), either by aerial photography or additional field work (i.e., placement of transects through special habitat types). Cover codes need to be evaluated and standardized for all HSI curves and transect data. Additional information which may become available in the future should also be reviewed and target flows be revised accordingly. Any new information on physical microhabitat variables that may be forthcoming would follow the procedures outlined above for reducing and analyzing the data. Recommended Tarqets: Flows at and below 1100 cfs should not be reduced beyond their present frequency of occurrence. Flows between 0 and 800 cfs should be improved by any additional water available. Any additional available water should first be applied to improve the lowest flow conditions below 800 cfs from June 15 to August 31. Flow pulses during other periods of the year are important to maintenance of fishery and aquatic ecology and are addressed by the wet meadow recommendation. Decreases in flows below a 1100 cfs target reduce availability of the best fishery habitat as presented by PHABSIM model output. Specialized habitats such as backwaters, sloughs, and side channels also become less available at flows below 1100 cfs and will result in the reduction of important deep water habitats along the river edges, specialized spawning and nursery habitats, and prevalence of vegetated shoreline habitats along sandbars and river banks. An 1100 cfs flow was formerly recommended by the Nebraska Game and Parks Commission during winter to reduce the incidence of ice cover on the river and maintain a foraging area for bald eagles. Flows reduced below 800 cfs will increase both the frequency and duration of lethal water temperatures throughout the central Platte River. Flow reductions may increase the potential for non-native species (i.e., Gambusia affinis) that are more tolerant of adverse conditions to displace native species (i.e., plains topminnow) (Pflieger 1975, Lee and Burgess 1978, Lynch 1988) thus changing both the species composition and abundance of the central Platte River forage fish community. This recommendation will aid in meeting the stated goal (Biology workgroup 1990): "to provide an adequate riverine environment to sustain the maximum diversity and abundance of forage fishes needed to support the recovery goals for endangered species." 12