366 U.S. BUREAU OF FISHERIES 



themselves ; and only 13 percent had moved upstream from the point 

 of liberation. On the other hand, in the case of the brook trout, 61 

 percent were taken upstream from the pools where liberated; 23 

 percent from the pools themselves; and only 16 percent had moved 

 downstream. 



Complete observations on this experiment will not be available un- 

 til after the freshets in the spring of 1934, but it has already shown 

 conclusively that hatchery reared rainbows, as well as brook trout, 

 are fully able to care for themselves when thrown on their own 

 resources. 



(JaUfomia trout investigations. — The investigations of problems 

 relating to the trout of California were carried on with the same 

 personnel as in 1932. As a result of experience gained during the 

 past year, it has been decided to modify in several important respects 

 the program originally adopted for the investigations. Briefly the 

 program as now developed calls for intensive work on two major 

 projects with additional work on several minor projects, which wdll 

 be carried on as time permits. One of the major projects which is 

 concerned with trout problems relating to Sierran lakes and streams 

 is under the immediate supervision of Dr. P. R. Needham, who is 

 also in charge of the California investigations as a whole. The other 

 major project is under the immediate direction of A. C. Taft and 

 deals primarily with problems relating to sea-run steelheads. This 

 project includes extensive studies in several coastal streams with 

 especial attention to the Klamath River. 



The minor projects include the planting of large numbers of 

 marked trout in the Truckee River and Angora Lake, experiments 

 in developing selected strains of California trout at the Hot Creek 

 rearing ponds in Mono County, and the development of a stocking 

 jDolicy for w^ater reservoirs near San Diego. 



Work on environmental conditions in trout streams carried on 

 during the past year has brought to light a number of new and 

 interesting facts. Seasonal food studies made in Waddell Creek 

 near Santa Cruz in August, November, March, and May, give a 

 yearly average of approximately 198 pounds of insect food per acre 

 of riffle area. Pools produced only 54 pounds per acre. On the 

 other hand, Waddell Creek Lagoon averaged over 250 pounds per 

 acre. While this stream produces principally insect food above the 

 Lrackish water area, lagoon foods consisted almost entirely of crus- 

 taceans, of which 2 amphipocls, Ganvniams confervicolis^ and Coro- 

 phium spinicorne^ and 1 isopod, Exosphaeroma oi'egonensls, offer 

 abundant food to young salmonoids. In numbers, an average of 

 over 10,000 crustaceans were found per square meter in the lagoon 

 bottom, while the riffles in the stream above averaged only about 

 •6,500 organisms to the same area. 



In the Feather and Merced Rivers about the same amount of food 

 was found to be present in winter as in summer, slightly more being 

 present in winter. Streams in northern California, both coastal and 

 Sierran, were found to be much richer in food than Sierran and 

 coastal streams in the central and southern parts of the State. 



The steelhead studies started at Waddell and Scott Creeks in 

 1931 have been continued. These two streams which are small in 

 size and very similar in physical characteristics offer particularly 



