Beacham et al.: Population structure of Oncorhynchus keta across the Pacific Rim 
253 
other, including populations from the Kuskokwim River 
in western Alaska and Nushagak River from northern 
Bristol Bay in the dendrogram cluster. 
Geographically-based regional clustering was observed 
in the populations surveyed south and east of north- 
ern Bristol Bay. Populations from southern Bristol Bay 
formed a distinct cluster in 98% of dendrograms evalu- 
ated, with bootstrap support observed for populations 
from the western south coast of the Alaska Peninsula, 
eastern south coast of the Alaska Peninsula, Kodiak 
