possibly non-hybridized rainbow trout and early and late generation hybrids between rainbow and westsicpe cutthroat 

 trout. 



Rattlesnake Creek "Hybrids" 3090 " '■ 



Of the 10 fish in this sample, nine possessed PINE fragments characteristic of rainbow trout at all six diagnostic 

 loci tor this fish that were analyzed. These individuals also possessed PINE fragments characteristic of vvestslope 

 cutthroat trout at all seven diagnostic loci for this fish that were analyzed. These nine individuals, therefore, appear to 

 be first generation hybrids between rainbow and westslope cutthroat trout. The remaining fish in the sample (20-86) 

 possessed all seven fragments characteristic of westslope cuttliroat trout, but only five of the six fragments 

 characteristic of rainbow trout. Thus, this individual could be a first generation backcross to westslope cutthroat trout 

 or it could be a first generation hybrid with rainbow trout PINE genetic variation that is indistinguishable from that 

 usually characteristic of westslope cutthroat trout. 



Rattlesnake Creek "Rainbows"3091 



All of the fish in this sample except two definitely appear to be late generation hybrids between rainbow and westslope 

 cutthroat trout with a predominant rainbow trout genetic contribution. They possessed PINE fragments characteristic 

 of rainbow trout at five or six of the six diagnostic loci for this fish that were analyzed, and they also possessed PINE 

 fragments characteristic of vvestslope cutthroat trout at one or two of the seven diagnostic loci for this fish that were 

 analyzed. The two exceptional individuals (21-80 and 21-81) possessed PINE fragments characteristic ofonly 

 rainbow trout suggesting they may be non-hybridized rainbow trout, but it is also possible that they are simply late 

 generation hybrids that by chance did not possess fragments characteristic of westslope cutthroat trout at the diagnostic 

 loci analyzed. 



Rattlesnake Creek "Cutthroat"3092 



All of the individuals in this sample except one possessed PINE fragments characteristic ofonly vvestslope cutthroat 

 trout suggesting they may be non-hybridized westslope cutthroat trout. The exceptional fish (21-96) possessed PINE 

 fragments characteristic of westslope cutthroat trout at all seven diagnostic loci for this fish that were analyzed, but it 

 also possessed PINE fragments characteristic of rainbow trout at three of the six diagnostic loci for this fish that were 

 analyzed. This fish, therefore, is undoubtedly of hybrid origin between westslope cutthroat and rainbow trout and 

 based on its genetic characteristics it may be a first generation backcross to westslope cutthroat trout. ^- 



Thompson Creek 3093 ;■ : 



PINE fragments characteristic ofonly westslope cutthroat trout were detected in the sample. With a sample size of 

 30 individuals, we have a 97% chance of detecting as little as a one percent rainbow trout genetic contribution and a 

 91% chance of detecting as little as a one percent Yellowstone cutthroat trout genetic contribution to a hybrid swarm. 

 Although we cannot reasonably exclude the possibility that this population may be slightly hybridized with 



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unless fiirther data indicate otherwise. 



Cold Creek 3094 



PINE fragments characteristic ofonly westslope cutthroat trout were detected in the sample. With a sample size of 

 24 individuals, we have a 94% chance of detecting as little as a one percent rainbow trout genetic contribution and an 

 85% chance of detecting as little as a one percent Yellowstone cutthroat trout genetic contribution to a hybrid swarm. 

 Thus, we cannot reasonably exclude the possibility that this population may be slightly hybridized with rainbow trout. 



