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<br />Although this system could be condensed to a four level system where A-rated populations would <br />be those with no indication of hybridization and B-rated populations would be those where fewer <br />than 15% of genetic markers or phenotypes indicate hybridization, the gradations in these A and B <br />categories provide the resolution that. may help fine tune genetics management as more genetics . <br />information is gathered. All Colorado and Wyoming populations with genetic information available <br />are des~ribed using this system. <br /> <br />Utah proposes to describe the genetic purity and potential for hybridization of their <br />populations using an index based on stocking history, meristic information, and molecular data. <br />This method has not been fully implemented and it is unclear how it compares to the method in use <br />in Colorado and Wyoming. <br /> <br />C. Viability or Stability: <br /> <br />The Coordination Committee adopted a definition of population viability based on criteria <br />from Rieman and McIntyre (1993). However, further study by the Biology Committee determined <br />that these criteria were not helpful to the CRCT conservation program at this time. Some small, <br />isolated populations of CRCT have been stable for many years and it is clear that there are <br />significant uncertainties surrounding ecological requirements for persistence of this species. <br /> <br />The Combined Committees agreed on the need for a consistent way to describe the condition <br />of the different populations across the range of CRCT so that it would be clear which populations <br />were stable and which were at risk of decline. They developed the concept of a stability index that <br />would describe the variation in condition over the range of existing populations using factors known <br />to be critical to CRCT survival. Although such an index would not predict absolute viability or <br />probability of persistence, it could give flexibility in describing CRCT populations as they exist <br />today and provide a framework for measuring progress in improving the conditions for those <br />populations. <br /> <br />However, after considerable effort toward developing this index within the necessary time <br />frame, there was still enough uncertainty among team members on its structure and utility that the <br />concept was tabled until a decision could be made either to continue with its development or use <br />simpler measures of stability. <br /> <br />D. Baseline: <br /> <br />The Combined Committees agree and want to emphasize that most waters in the historic <br />range ofCRCT are potential restoration areas. Factors such as presence of hybrid fish or absence <br />of barriers should not be viewed unilaterally as precluding inclusion of the water in the CRCT <br />restoration process. To facilitate this broader perspective, the baseline for CRCT conservation in <br />the tri-state area was defined as all waters with potential to support CRCT given appropriate <br />management. <br /> <br />Rather than selecting a single subset of these waters as a standard for assessing the range- <br /> <br />March 1999 <br /> <br />13 <br />