Jtme 29 through August 2, 1945, 39 brown trout passed through the gates 

 of the Lewiston fish-counting weir* Six specimens taken for study had 

 an averege weight of 5.7 pounds and an average length of 23.4 inches. 

 Their sex products were further developed than those of steelhead, but 

 less than salmon taken at the same time* Less conspicuous but larger 

 migrations occur during November and December* Although these fish have 

 not been observed spawning in the Trinity River during this study, local 

 residents report having seen them spawning in the upper main stream amd 

 its tributaries from late December until early February* 



Several young brown trout were usually taken in the fyke nets at 

 Lewiston dvu-ing the week following the first fall rain. A few young, 

 near or in their second year, were taken through the remainder of the 

 winter months. Fry of this species, that had recently left the giravel, 

 were taken by fyke nets on very rare occasions in March and April* It 

 is possible that the brown trout of Trinity River migrate to the sea as 

 do representatives of the same species in Europe, although no direct 

 evidence is yet available to demonstrate such movement* Scales from 

 the specimens taken at Lewiston were so resorbed that positive age and 

 growth determinations could not be made* 



Rather limited populations of eastern brook trout occur in the 

 colder waters of the upper extremities of the Trinity River and its 

 tributaries. They are caught in fair numbers by sportsmen who frequent 

 the higher, primitive areas* These fish do not attain a verj' large size 

 in the drainage, but their gaminess and limited distribution make them 

 highly desirable to many sportsmen. 



Anadromous Fishes 



Four anadromous or sea-run fishes have been recognised in the 

 Trinity River during the course of this investigation* These are the 

 three-toothed lamprey, Entosphenus tridentatus (Gairdner)j the king 

 salmon, Onoorhynohus ts ohawy ts oha (Walbaum) ; the silver salmon, 

 Onoorhynohus kisutch (Walbaum) } and the steelhead trout, Salmo 

 gairdnerii (Richardson) * 



King salmon 



Comneroial and sports fisheries 



King salmon have long been sought by Indians, comnercial fisher- 

 men, and sportsmen as one of the most abundant aild desirable of the 

 Pacific salmons* The part played by the Trinity River in supplying 

 the salmon fishery of California is not definitely known, but some 



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