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SPRRIP - ED OFFICE FINAL 6 06/24/2008 <br />1 PLATTE RIVER RECOVERYM IMPLEMENTATION PROGRAM <br />2 Questions /Comments on Whooping Crane Data Analysis Report <br />3 <br />4 • Initially the decoys were not to be used as a detection trial but to train the observers. This <br />5 was for several reasons including things like do painted decoys have the same detection <br />6 probability as a live bird or group of birds? Is it really independent if the same contractor <br />7 places them that reports them and after some time all observers recognize they will only be <br />8 on conservation lands? I think those issues should be mentioned but more importantly is that <br />9 due to the random nature of placement, decoys got stuck in areas of trees, very narrow <br />10 channels etc., where they are hard to detect but whooping cranes may not go. Therefore if <br />11 we are going to use decoys for detection trials we need to analyze the effects of land cover, <br />12 channel width, etc. on the detection probability of the decoys and compare that to where <br />13 cranes were found. <br />14 <br />15 • I am probably missing something on this one but, many of the models indicate a large portion <br />16 of open water is a good predictor of use. However, Table 6 does not show open water ever <br />17 being used. While the water may be in the landscape if the birds never use it is it really be <br />18 selected for? <br />19 <br />20 • What is relative probability of use? If we make an unobstructed view large enough to have a <br />21 relative probability of use of 1 are we guaranteed to see a crane there or is it that there is <br />• 22 twice the chance of seeing one in an area that has an unobstructed view with a corresponding <br />23 value of 0.5. <br />24 <br />25 • Based on comment number 3 above I would like to see histograms of actual use broken down <br />26 by say 50 or 100 foot intervals and some simple ratios of use verses availability for those <br />27 relative use probabilities. While the given functions are nice lines and give the top end of <br />28 what seems to be important to whooping cranes I would like to see some discussion of <br />29 how they can be used to design management. We can strive to achieve the very peak of these <br />30 functions but if we cannot get there due to geology, hydrology whatever we need to at least <br />31 make sure we are not building something cranes avoid. <br />32 <br />33 • When cranes spent more than one night and changed channel use sites was it always to wider <br />34 channels? <br />35 <br />36 • How many of the 165 transects used in the HECRAS model were measured, interpolated <br />37 and /or synthesized? <br />38 <br />39 • I think I have it figured out but the description of how available points on the local scale were <br />40 obtained could use some clarification. <br />41 <br />42 • Was area clear of visual obstruction actually measured or calculated from average distance to <br />.43 obstruction? And are these only channel measurements or in agricultural areas also. <br />44 <br />