Quinn et al Origin and genetic structure of Oncorhynchus tshawytscha 



over all loci was 0.051, and ranged 

 among individual loci from 0.002 

 for mAAT-2* andPEP-D2* to 0.217 

 for GPI-B2* (Table 4). Matrices of 

 pairwise comparisons of two mea- 

 sures of genetic distance (Cavalli- 

 Sforza and Edwards, 1967; Nei, 

 1972 ) among populations ( Table 5 1 

 provided the basis for identifying 

 possible distinct population group- 

 ings reflected in this diversity. The 

 UPGM projection of pairwise mea- 

 sures of Nei's distance (Fig. 3A) 

 separated the South Fork Eel 

 River fish from the remaining col- 

 lections. Two subgroups, compris- 

 ing the Sacramento and NZ popu- 

 lations, were also apparent. In the 

 Sacramento River subgroup, the 

 Merced Hatchery (San Joaquin 

 River) fall-run fish diverged from 

 the Battle Creek (Coleman Hatch- 

 ery), Feather River, and American 

 River (Nimbus Hatchery) fall-run 

 fish and from the wild Sacramento 

 River winter-run fish. The three 

 NZ populations grouped more 

 closely within their subgroup than 

 did the Sacramento River popula- 

 tions within theirs. The matrix of 

 Cavalli-Sforza and Edwards dis- 

 tances (Table 5) revealed a com- 

 parable UPGM clustering (not pre- 



0.04 

 H 1 — 



03 



— I 



n 02 



— (— 



00 



— I 



05 



1— 



004 



1- 



03 

 1— 



j£ 



-n 



Battle Creek 

 Fealher River 

 American River 

 Upper Sacramento 

 Merced River 

 Rakaia River 

 Wailaki River 

 Waimakariri River 

 Eel River 



0.02 



1- 



001 



— I— 





tE 



Bailie Cr (Fall '87) 

 Bailie Cr (Fall '82) 

 American R (Fall '87) 

 Fealher R (Fall '82) 

 Fealher R (Fall 87) 

 Fealher R (Spring '82) 

 Up Sacr R (Winter '87) 

 Merced R (Fall '87) 

 Rakaia R ('93) 

 Waitaki R ('93) 

 Waimakariri R (93l 

 Eel R (87) 



Figure 3 



UPGM phenograms of chinook salmon populations from California and New 

 Zealand based on pairwise Nei's ( 1972) relative genetic distance measures. (A) 

 Data from 24 polymorphic loci for collections 1-9. (B) Data from 10 polymorphic 

 loci for collections 1-12 (see Table 4 for details). 



