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NOTES ON AN INVESTIGATION OF THE MOVEMENT AND 



RATE OF GROWTH OF THE QUINNAT SALMON 



FRY IN THE SACRAMENTO RIVER. 



By N. B. SCHOFIELD, of California Fish Commission. 



Aided by the knowledge gained in the study of the habits, move- 

 ments, and rate of growth of the young salmon in Marin County, we 

 were better enabled to carry on the more difficult work of finding out 

 the movements and rate of growth of the salmon fry in the Sacramento 

 River. 



The work was begun in the headwaters of the Sacramento in the 

 neighborhood of Sisson in August, 1897, and has been continued at 

 intervals to the present time. During the present spring the United 

 States Fish Commission has taken up the same work in the Sacra- 

 mento, and in the following report I have made free use of some of the 

 results of their work, especially of their work in the brackish and salt 

 water of Suisun and San Pablo bays. 



To make clear what is to follow I will explain that although a few 

 salmon may spawn in some of the tributaries of the Sacramento in 

 almost any month of the year, the vast majority of them spawn at two 

 separate and distinct times. Eggs deposited by the spring run hatch 

 in October, and the eggs from the fall run hatch the following Febru- 

 ary. After hatching it is another month before they begin to swim 

 around and feed. 



The adult Quinnat salmon, in its journey up the Sacramento for the 

 purpose of spawning, never reaches Sulloway Creek, and it very rarely 

 reaches a point as far up the Sacramento as the mouth of the Sulloway. 

 The young Quinnat salmon found in the Sulloway and this part of the 

 Sacramento are from the State hatchery at Sisson, and, knowing the age 

 of the fry liberated, it is possible to estimate very accurately their rate 

 of growth. 



On August 28, 1897, I seined Sulloway Creek, and found the salmon 

 fry quite plentiful. To better illustrate their number, in one haul, 

 through a hole three feet deep, ten feet wide, and fifteen feet long, I 

 caught twenty-seven young salmon. In other parts of the creek they 

 were just as plentiful. None were found above the point where they 

 had been liberated. These fry had been planted in February, and at 

 the time their yolk sacs were absorbed about March 10th their aver- 

 age length was 1.35 inches. On August 28th, five months and twenty 



