100 150 200 250 



FROM MOUTH OF RIVER (KM.) 



Figure 9. — Total catch of Cyprlnldae, Catostomldae, Cen- 

 trarchidae, Cottidae, and Salmonldae from the main 

 stem of the Yakima River In 1957 and 1958, by sampling 

 site. 



100 



- 



100 



50 100 150 200 250 281 



DISTANCE FROM MOUTH OF RIVER (KM.) 



Figure 10.— CPUE (catch per unit of effort) of Pacific and 

 western brook lamprey (combined) from the main stem 

 of the Yakima River in 1957 and 1958, by sampling site. 



distribution of the fry slowly expands 

 downstream. By the end of summer the 

 salmon are common to kna. 153, but 

 the greater numbers are above km. 201. 

 An active seaward migration begins 

 about February and is completed by 

 June. During March to June the abun- 

 dance of salmon is increased by the 

 presence of two year classes. 



Fall Chinook salmon spawn below 

 km. 1 53, and their progeny move toward 

 the sea shortly after emerging from the 



100 





 100 

 100 





 100 

 100 





 100 

 100 





 100 

 100 





 100 

 100 





 100 

 200 



200 - 



APRILS TO JUNE 20, 1957 



JULY 15 TO AUGUST 7, 1957 



SEPTEMBER 18 TO OCTOBER 18, 1957 



NOVEMBER 12 TO 22, 1957 



JANUARY I TO 21, 1958 



MARCH 3 TO 21, 1958 



MAY 12 TO 20. 1958 



Figure 11.— CPUE (catch per unit of effort) of Chinook and 

 coho salmon (combined) from the main stem of the Ya- 

 kima River In 1957 and 1958, by sampling site and date. 



gravel. Fall chinook salmon fry prob- 

 ably were not collected in this study. 



The Naches River produces a con- 

 siderable portion of the salmon of the 

 Yakima watershed. Recent indications 

 are that only spring chinook salmon use 

 the Naches River (Major and Mighell, 

 1969). Supplemental collections suggest 

 that salmon smolts of the Naches River 

 do not enter the main Yakima River in 

 numbers until January. 



Mountain whitefish (6) 



Normal range: Km. to 64 and 113 to 

 258 (fig. 12, table A-3). 



Periods of abundance: Mountain white- 

 fish were more abundant from Sep- 

 tember to March than at other times 

 of the year. 



Comments: Shifts in abundance indicate 

 seasonal migrations. In November, the 

 mountain whitefish that were pre- 

 viously abundant between km. 120 and 

 209 seemed to have moved toward the 

 upper portion of the study area, and 

 the nunr^bers of whitefish from the 

 mouth to km. 72 increased. Because 

 the number of whitefish in the lower 

 river increased at the normal time of 

 spawning and because almost all of 



10 



