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exposed sand or gravel bars, and islands all seem qualitative in the context used and without much <br />• defimition. But we may need to have definitions to evaluate. Otherwise channel characteristics from <br />whooping crane roost sites (Table 3) are unobstructed width range 172 -1500 feet (mean 845, S.D. 254), <br />percent wetted range 24 -100% (mean 84 %, S.D. 20 %), area less than 0.7 feet deep range 6 -72% (mean <br />40 %, S. D. 16 %). Approximate visibility upstream and downstream not consistently reported and assumed <br />to be estimates. Percent of river or total acres that would meet the width and length criteria could be <br />calculated off 1998 GIS analysis. Distance to wet meadow has not calculated. <br />Non - complex definition of whooping crane roosting habitat is a non - riverine wetland within the Program <br />associated habitat area, with some area less than 18 inches (45 cm) deep, shallow sloping banks, lacking tall <br />vegetation. Size at least 10 acres including surrounding uplands. <br />Howe (1985) found of 69 roosting wetlands used by radio marked whooping cranes 15% were smaller than <br />0.1 ha, over 40% were less than 0.6 ha and the largest used in Nebraska was 8.8 ha. Based upon incidental <br />observations of roosting whooping cranes Austin and Richert (2001) report "roosting cranes were <br />commonly observed on large ( >40 ha) wetlands. They also found that if observations from large managed <br />wetlands were excluded there was a more even distribution of palustrine wetland sizes used. <br />Average water depth at specific sites used for roosting ranged from 5 to 46 cm (mean 20+ 9cm) (Austin and <br />Richert 2001). Generally whooping cranes do not venture into water deep enough to cover the tibiotarsal- <br />tarsometatarsal joint (I believe this is about 30 cm although I did not have time to look it up) (Howe 1985). <br />There is additional data on both of these definitions in Johnson and Temple (19 80) as well as some of the <br />crane workshop proceedings and some of the papers already cited in the baseline. I just did not have the <br />time to go through them all and referenced the ones I knew what they said, but you get the idea hopefully. <br />What percentage of the river is currently in this condition? How do the channel width characteristics <br />• measured at past whooping crane roost sites relate to those conditions? <br />This will probably prove to be a very frustrating endeavor for whoever does it. If no data or information <br />can be found to support the characteristics that should be clearly stated. <br />If you have any questions feel free to call. <br />• <br />