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group sightings. Bias in the estimate of channel characteristics will increase with the difference <br />in channel character between the sighting location and the gage location. <br />Recommendation <br />Given these arguments, we recommend the HECRAS method over the gage method because of <br />the quality of the model output and the benefits derived from using an established model. Lisa <br />Fotherby's report indicates the gage method is fine if the sighting is in a similar channel as the <br />adjacent gage, but this is not likely for all or even most of the crane group sightings. We prefer <br />t„ „o,- tiiP enmi. a.1;,,,-tmP„t method for every wh � sighting in the analysis, further <br />supporting the HECRAS model. <br />Lisa Fotherby has provided an updated budget for completing the water surface area adjustment <br />for all of the whooping crane sightings (phase 2). The original budget for the pilot analysis <br />(Phase I) and follow analysis completion (Phase II) is $18,312.00. The budget for Phase I was <br />$4,312.00, leaving $14,000.00 for Phase II. The revised Phase II budget is $37,120.00, an <br />increase of $23,120.00. This increase occurred for several reasons. Initial budget estimates for <br />using HECRAS were based on Lisa's assumption that HECRAS would be used to obtain an <br />estimate of the water surface elevation at use sites for the time the cranes were actually using the <br />area. These budget estimates did not include obtaining the three parameters that are necessary <br />for habitat selection analysis: depth, wetted width, and sandbar elevation. Tasks 2 and 3 in <br />Lisa's budget have been added to extract these parameters from the HECRAS output. In <br />addition, initial budget estimates were based on 109 whooping crane sightings. There are <br />actually 164 used locations in wetted channel/barren beach/bar habitats. The measured channel <br />profile data is available for all these points, although because whooping cranes used the same <br />areas on multiple points in time, there are only 75 locations with measured profiles. Budget <br />estimates did not take into account these numbers or the fact that each of the 75 locations <br />actually has 3 transects that could be input into HECRAS and there are 135 daily mean flows <br />that will need to be run through the model. <br />The habitat selection analysis of the whooping crane data proposed by the Technical Committee <br />uses Resource Selection Function statistical procedure. To estimate resource selection functions, <br />we need the same set of parameters estimated on a set of random or available locations. For this <br />set of data, we can use HECRAS model output for transects at 0.10 mile increments throughout <br />the study area. The revised budget also includes time to extract from HECRAS the needed <br />parameters for the entire study area at the time of each crane sighting (sandbar elevation may not <br />be available for this analysis). Data on these transects will be adequate for calculating study area <br />wide selection functions. The original proposal for habitat selection analysis included the <br />calculation of local area selection functions for which we could use the HECRAS output on the <br />transects at 0.10 mile increments adjacent to the crane use location for the available dataset. We <br />may find there is inadequate variation in the parameters on the adjacent transects because the <br />model output is subject to the spatial intensity of transects input into the model. In other words, <br />WEST, Inc. Page 2 2/5/2008 <br />