Table 5.— Spawning areas of coho salmon in the Columbia River Basin— past and present— Continued 



Num- 

 ber^ 



Stream 



Length 



Distance 

 above 

 mouth- 



Spawning areas 



Present 



Past 



Notes 



References* 



16. 

 17. 



IS. 



19. 



19E. 



Milton Creek 



Scappoose 

 Creek 



Salmon Creek 



Willamette 

 River 



19A. Johnson Creek 



19B. Clackamas 



River 



19B1. Eagle Creek 



19B2. Collawash 

 River 



]9C. Abernethy 



Creek 



I9D. Tualatin 



River 



Molalla River 



19F1A. Willamlna 

 Creek 



Km. Km. 



32 144 Middle portion. 



10 146 North and 



South Forks. 



303 



35 



128 



150 



162 



L'pper part. 



Same as now. 

 More now. 



Lower stream. 



80 



40 



26 



93 



40 



45 



58 



Most of main 

 streajn. 



Upper portion and 

 lower North Fork. 



Lower 18 km. 



Lower 1 1 km. of 



main stream, lower 

 10 km. Hot Springs 

 Fork. 



Middle section 

 main stream and 

 tributary, Holcomb 

 Cr. 



l_'pper Tualatin R., 

 McKay. East Fork 

 Dairy, Gales, and 

 Scoggins Creeks. 



Upper and middle 

 portions. North 

 Fork Milalla R. 



Same as now. 



Probably some of 

 stream areas in- 

 undated by dams. 



Not as large as now. 



same as now. 



Not as large as now. 



Species introduced. 



Species introduced. 



32 



59 



Lower half Coast 

 Cr. and East Fork. 



Species introduced. 



Small stream, supports small run. A 29 

 few use lower part of tributaries. 



Pollution is problem in Scappoose Bay. 29 

 Excellent spawning gravel throughout 

 North Fork; South Fork has excellent 

 gravel in upper portion. Ladder at 

 Bonnie Falls opened more area. 



Fair spawning areas in upper half of 1, 35 

 stream. Lower stream polluted from 

 agriculture and gravel is compacted with 

 silt. 



Willamette R. is a migration route and 29, 40, (*) 

 possibly a rearing area. O.F.C. has 

 made a concerted effort to establish coho 

 salmon (also fall chinook) in tributaries 

 of this system. It appears that first- 

 generation fish and some second-gener- 

 ation fish have returned. 



Supports a few coho salmon. Best 29, 40 

 spawning gravel in upper portion of 

 stream. 



Falls block migration in North Fork. 29, 40 

 Lower tributaries (not shown on map) 

 have moderate-sized runs. Good pros- 

 pects for increasing run. 



Good spawning area throughout stream. 29, 40 

 Migration limited by falls. Recent im- 

 provements in passage at falls in lower 

 18 km., and Eagle Creek National Fish 

 liatchery increased production in recent 

 years. 



Gravel plentifully dispersed in areas 29, 40 

 of lower gradient; heavily forested, 

 mountainous area 



Obstructions removed, 1953-55. Now 

 supports fair numbers of coho salmon 

 as well as other salmonids. 



29, 40 



Decreased summer flows because of over- 29, 40. (*) 



appropriation of water. Believed coho 



salmon not present until introduced 



about 1920; now believed to have 



largest run migrating above Willamette 



Falls. 



Used as passageway and rearing area. 29, 40, (*) 

 No coho salmon known before 1952 when 

 juveniles were liberated into Milk Cr. 

 and the North Fork. Adults returned 

 to spawn. Other releases made in var- 

 ious tributaries. First generation returns 

 indicate run may be successful. 



Most of stream has mud-silt bottom and 29. 40 

 slight gradient ; used as passageway. 



Spawning areas are spotty, lower areas 29, 40, (^) 

 are silty, middle and upper areas have 

 mostly heavy gravel and bedrock, but 

 suitable gravel is interspersed. 



Abiqua Falls blocks run about 32 km. 29, 40, {*) 

 up. Coho First introduced in 1958. 

 This and subsequent plants have estab- 

 lished runs. 



This stream slocked for several years, 29, 40, (*) 



and returns indicated that it has good 



potential. 



Used as passageway. 29, 40 



Believed that salmon not present in 29. 40, (*) 

 \'amhill system before 1954. Yearly 

 average of over 100,000 juveniles re- 

 leased into better tributaries. Small 

 runs returned to most of tributaries. 



Plants starting in 1954 are thought to 29, 40. (*) 

 have originated runs in this stream. 



See footnotes at end of table. 



16 



