112 FISH AND GAME COMMISSION 



Castle Lake trout investigations — Report for 1948. Second phase : Eastern 

 brook trout. (Siskiyou County). Submitted May 24, 1949. 19 pp., including 20 

 tables. 



Abstract : Anglers' catch for 1948 was 5,199 eastern brook trout by 1,213 

 anglers for an average of 4.3 per day and 1.36 per angler hour. Two year groups were 

 represented. Up to the end of the 1948 season 46 percent of the 1947 yearling plant 

 had been caught and 8.9 percent of the 1947 fingerling plant. 28 percent of the angler 

 days resulted in zero catches. The largest were continually being caught so that 

 no large fish ever developed. There was a large movement out of the lake with the 

 overflow in the fall. 1,653 fish went down the outlet stream in November. Growth 

 rate was relatively slow, slower than in the Mt. Shasta Hatchery. The C. F. was 

 only medium, the lake may be slightly overcrowded. Plankton seemed to be returning 

 after having been killed out by rotenone. Pounds of bottom food was estimated at 

 149 per acre. 



Sacramento River Test Stream report for 1948. Submitted July 22, 1949. 17 

 pp., 5 figures. 



Abstract : Results of the creel census on the South and Middle Forks of 

 the Sacramento River and on 15 lakes of this basin are reported. Following is a 

 brief summai-y for the 2 forks : South Fork — 564 anglers ; 2,500 total catch ; catch 

 per hour 1.44 ; wild rainbow 1,749 ; hatchery rainbow 696 ; eastern brook .54 ; brown 

 1. Middle Fork — 122 anglers ; 839 total catch ; catch per hour 2.40, wild rainbow 

 698, hatchery rainbow 140 ; eastern bi'ook 1. 



Warren, Charles E. (Student Biologist) 



The extent and effect of pollution resulting from the Modesto Sewage Farm 

 Levee Break. Submitted August 30, 1949. 12 pp., including 5 figures and 3 tables. 



Abstract : A break occurred in a levee at the Modesto sewage farm on 

 August 21, 1949. This report covers an investigation of the extent and effect of" 

 damage done as a result of the sewage break. Through oxygen depletion much fish 

 life was destroyed in the Tuolumne River and down the San Joaquin River to Salmon 

 Slough. Here the main pollution passed into Salmon Slough, dissipating itself about 

 seven or eight miles below its mouth. Damage was inflicted on most species present, 

 but the loss of fork-tailed catfish was probalily most important. The damage to the 

 sport fishery on this fish alone was estimated at $135,000. 



WoodhuU, Chester 



Observations on handling the sampling gill net. Submitted May 19, 1949, 8 pp., 

 5 figures. 



Abstract : Observations on methods for easy handling of the sampling gill 

 nets are noted. Directions are included for the construction. A gill net rack that 

 facilitates laying and hauling of the nets, especially for one man operation. Four 

 photos illustrate operation of the net and rack. 



