23 



thirty. Below Chico this number fell off, and we caught only four or 

 five in a haul. At a point two miles below Knights Landing the last 

 salmon was caught, although we seined thoroughly between this point 

 and Sacramento. 



Belqw Red Bluff the salmon were very uniform in size, averaging 2.4 

 inches. It should be remembered that while we were making this trip 

 small salmon of this same size were being caught in salt water. They 

 were all hatched from the fall run of salmon, and it had been but a 

 little over two months since they were old enough to feed. Their rate 

 of growth after the absorption of the yolk sac was almost .5 of an inch 

 per month. 



Early in July Mr. Rutter again made the trip down the Sacramento, 

 but was unable to find any salmon whatever below Battle Creek. The 

 run of small salmon out of the river had ceased. 



The conclusions to be drawn from these observations are: That 

 immediately or very shortly after the salmon are old enough to feed and 

 begin to swim about they begin to drift down the river, and within two 

 months of this time they reach salt water. By the end of the fourth 

 month the run is over, and those remaining in the headwaters of the 

 river stay until the high waters of the following winter. The number 

 of these thus remaining is small compared with the number running 

 out immediately. 



The rate of growth of the salmon during the first two months after 

 absorbing the yolk sac, taken from an average of all the salmon taken 

 on the Sacramento, was .42 of an inch per month. Those remaining 

 after two months do not grow so fast. Salmon from four to eight months 

 old show an average gain per month of a little over .30 of an inch. 



