83 



CHEHALIS rAlX CHINOOK RUN SIZE 



■ lid «i ru« iK 



ffiBH 



1»70 1111 It 1« ltT€ Iff It tO It t2 1»M 



Figure S. CbehaLi Basin fill Chinook terminal area tun size (WDF 

 unpublished data). 



because of poor poet-release survival 

 of Simpson Hatchery smolts (Brix, 

 WDF, pere. comm. ) . Hatchery 

 production has had relative success 

 on the Humptulips, the difference 

 possibly being due to the inner 

 Harbor pollution block mentioned 

 earlier. 



Fall o^tinook Marine Interception 



Fall Chinook are caught primarily in 

 the ocean troll fisheries off 

 southeast Alaska and northern British 

 Columbia. British Columbia fisheries 

 caught 68.9 percent of the Chehalis 

 fail Chinook marine catch throughout 

 the period for which tag returns are 

 available (Figure 9). The remaining 

 marine catch went to Alaska, at 19.7 

 percent, and Washington at 11.2 

 percent. 



Juvenile Chinook Production 



Seiler et al. (1992a) enumerated the 

 capture of Chinook salmon in a 

 floating inclined plane trap between 

 Oakville and Rochester between 1985 

 and 1990. Estimates of emigration 

 could not be made because trapping efficiency was not evaluated. The 

 following table roughly indicates the weak relation between smolt abundance 

 and the previous year's adult escapement upstream of Porter; little is 

 actually known about the relation between adult escapement and smolt 

 production. 



Figure 9. Fall Chinook marine interception patterns (PFMC and WDF 

 data). 



26 



