Catch year 1 



Basin 



Escapement 



91 



Terminal area hatcher v coho catch* 

 HumptullpB system Chehalis system 



Chehalis 



1984 

 198S 

 1986 

 1987 

 1988 



Wean 



36,589 

 10,873 

 40,448 

 13,667 

 60,330 



32,381 



Jiarine./terminal c 

 Est, total catch 

 Est. average run size 



i,8D3 

 1,074 



15,782 

 8,106 



19,676 



9,288 



8-72 

 80,991 



7,540 

 3,608 

 6,038 

 7,21S 

 2,e3-i 



5,447 



3.29 

 17,921 



98,912 

 131,000 



A Sairct: WDFi^ubli«h*dnm reeooauucoooaau proved by Diet S»one. 



S T af recovery oaia unavailable for prior yean. 



C See Table 9. 



Table 11. Chehalis Basin estimated hatchery coho catches and run size. 



CHUM SALMON 



Terminal Area Run Size and Escapement Coal 



There 

 spawn 

 years 



CHEHALIS 5ASXN CHUM RUN SIZE 



are no known sub-stocks of chum salmon in the Chehalis Basin based on 

 timing or location. Run size has averaged 53,000 over the last four 

 (Table 5, Figure 12). The trend toward larger run sites (Figure 12) may 



have to do with improving estuary 

 rearing conditions or ocean survival. 

 However, failure to meet the 

 escapement goal has become more 

 common in the past several years and 

 may jeopardize sustained recovery. 

 Adequate escapement, particularly 

 with chum, depends on accurately 

 predicting the terminal run size 

 since virtually all cateb i -3 i* else 

 terminal area. CnJ-cri-uia-Lsiy, this 

 is difficult due to unpredictable 

 year-to-year differences in marine 

 survival and age at return. 



70 71 74 7« 71 SO *I •« •< •* »0 



Fifure 1 2 - f*K*H«lit Baaio chum aalraan terminal arc* run size (WDF 

 unpublished data). 



34 



72-813 - 93 - 4 



