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2. Fall chinook interception represents Otehalis Basin chinook as a whole. No lagging midiei hive been 

 performed on Chehilii erring chinook, bul they ere auumed to neve the Mine far-northerly dinnbuuon «■ 

 couul Washington chinook stocka in general (Fraidenburg 1982, Scoa 1992 draft). 



3. Separate calculation for Humpwlips and Oiehalis systems adequately accounts for differing terminal 

 exploitation rates due to heaver exploitation of Humptulips fall chinook than Oiehalis fish (WDF, 

 unpublished data). 



4. Hatchery and wild fish contribute to marine and terminal fisheries in essentially the same way. Thi» is Ihc 

 accepted assumption in interpretation of PSC indicator atocka coasrwide (Scoo 1992 draft). 



Sprint «-hi~w»L Qtxch was omitted from calculations for anfkkxty, because this fishery would ha»e added 

 an uoigt of -ooJy about 200 fish to the Chehahs ryttem catch.'' Including tbia catch would alao have added to 

 the biaa deacribed is llctn I.A.I, above. 



Catch year Origin 



Expanded tag recoveries 



Che. basin Marine Ratio (Che.+Har. )/Che. 



Table 7. Tag recovery data used to expand terminal vild chinook catch to 

 estimate total catch including interception. 



COHO SALMON 



Chehalis Basin coho are biologically divided into two groups based on spawn 

 timing, but for fisheries management are treated as a single group (Stone, 

 WDF, pers. comm. ) • The largest, "normal" spawn timing group consists of both 

 hatchery and wild fish, which peaks in the Grays Harbor fishery in early 

 October and spawn in early December throughout the Chehalis Basin. The later- 

 spawning group is virtually all wild, returns in late November and December 

 and spawns in January-February, primarily in the major lower Chehalis 

 tributaries. 



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