Parker Lake 3098 



All of the fish in this sample possessed PINE fragments characteristic of Yellowstone cuttlL'-oat trout at two or mere of 

 the four diagnostic loci for this fish that were analyzed. Pi>.'E fragments characteristic of rainbow trout were also 

 detected in the sample at five of the six diagnostic loci for this fish that were analyzed. Finally, PINE fragments 

 characteristic of westslope cutthroat trout were detected in the sample at both of the diagnostic loci for this fish that 

 were analyzed. Neither the Yellowstone cutthroat nor the rainbow trout fragments were randomly distributed among 

 the tlsh in the sample. Significantly (chi-square; P<0.001) more fish possessed Yellowstone cutthroat trout fragments 

 at all the diagnostic loci analyzed and significantly fewer fish lacked or possessed a Yellowstone cutthroat trout 

 fragment at only one locus than expected by chance (Figure I). Likewise, significantly (chi-square; P<0.()0 1) more 

 fish possessed rainbow trout fragments at four or five diagnostic loci and significantly fewer possessed them at only 

 one or two diagnostic loci than expected by chance (Figure 2). Thus, although this population definitely contains 

 individuals of hybrid origin among Yellowstone cutthroat, westslope cutthroat, and rainbow trout it does not appear to 

 be a hybrid swarm. In contrast, the fish in the sample tend to have a higher Yellowstone cutthroat trout orrainbow 

 trout genetic contribution than expected in a hybrid swarm. This suggests that the lake niay be inhabited by two 

 somewhat reproductively isolated populations both of which are hybridized. Despite this possibility, from a practical 

 perspective the lake should simply be considered to contain a hybridized population with a predominant Yellowstone 

 cutthroat trout and a relatively minor westslope cutthroat and rainbow trout genetic contribution. 



West Twin Lakes 3099 



PINE fragments characteristic of Yellowstone cutthroat trout were detected in the sample at all four diagnostic loci for 

 this fish that were analyzed. PINE fragments characteristic of rainbow trout were also detected in the sample at all six 

 of the diagnostic loci for this fish that were analyzed, finally, PINE fragments characteristic of westslope cutthroat 

 trout were also detected in the sample at both of the diagnostic loci for this fish that were analyzed. The Yellowstone 

 cutthroat trout fragments appeared to be randomly distributed (chi-square: P>0.025; Figure 3) among the fish in the 

 sample, but the rainbow trout fragments were not as significantly (chi-square; P<0.001; Figure 4) more fish lacked 

 rainbow trout fragments or possessed them at all diagnostic loci than expected by chance. This suggests the lake may 

 be inhabited by two somewhat reproductively isolated populations both of which are hybridized. One population may 

 have a predominant rainbow trout genetic contribution and the other a significant westslope and Yellowstone cutthroat 

 trout genetic contribution. Despite this possibility, since all the fish in the sample were definitely of hybrid origin from 

 a practical perspective the lake should simply be considered to possess a hybridized population of westslope cutthroat, 

 Yellowstone cutthroat, and rainbow trout. 



Sincerely, : * > ^ . . 



Ben Wright 



Robb Leary ,„,. . . ... . 



