PROPAGATION AND DISTRIBUTION OF FOOD FISHES, 1922. 25 



Oregon, and California, and in the Territory of Alaska. The aggre- 

 gate output of these stations for the year amounted to 183,992,815 

 eggs, fry, and fingerlings of the salmon, as against a total of 146,- 

 107,040 the preceding year. Of the 1922 output 145,542,405 were 

 fingerling fish, while the fingerlings produced in 1921 numbered 

 92,066,730. 



AFOGNAK (ALASKA) STATION. 

 [Edwin Wbntworth, Superintendent.] 



For the fifth consecutive season since the destruction of the spawn- 

 ing beds by the volcanic deposit in 1912 there was an excellent run 

 of sockeye salmon in Letnik Lake and no trouble was experienced 

 in obtaining the desired number of eggs, notwithstanding the escape 

 of large numbers of fish over the racks during a period of high 

 water in early August. It is estimated that the season's eg^ col- 

 lection, which amounted to 53,835,000, was secured from approxi- 

 mately one-fourth of the salmon entering the lake. The work of 

 incubation was hampered by a scarcity of water, as a result of dry 

 weather extending through August and well into September. By 

 constant and assiduous attention, however, the stock was carried 

 through without abnormal loss, though the high temperatures pre- 

 vailing during the drought caused the eggs to hatch fully three 

 weeks earlier than under normal conditions. The stacked trays 

 were again used in holding the fry through the period of absorbing 

 the umbilical sac, with only nominal loss. During May, however, 

 a disease appeared among the 12,000,000 fry remaining on hand at 

 that time, and it soon became epidemic, causing a serious mortality. 

 All of these fry appeared normal at the time of hatching, the 

 trouble appearing just prior to the feeding stage, and in no in- 

 stance was the disease responsive to the usual methods of treatment. 

 There was some evidence that a similar affection obtained among 

 the migrating sockeye fingerlings at this time, and examples of the 

 fish from the lake and the hatchery troughs were forwarded to the 

 division of scientific inquiry for examination. 



With the purpose in view of reserving Letnik Lake solely for the 

 spawning of the sockeye salmon, the dam at the falls in Letnik 

 River was closed on August 25 and rendered effective service during 

 the fall and early winter in excluding Dolly Varden trout and silver 

 salmon. It was planned to install a trap in the river at this point, 

 to serve as a means for obtaining a count of the sockeyes entering 

 the lake, but the webbing shipped from Seattle for this purpose 

 was delayed en route. As an alternative racks were installed at 

 the outlet of the lake, and 37,653 sockeye salmon were counted 

 through between June 7 and July 1. 



A simple method of transporting the advanced fry to suitable 

 planting areas was tried with success. The trays containing the 

 fry were placed on a Yukon sled, with a tarpaulin folded around 

 them, and it was found that the young fish could be transported in 

 this manner without loss, even when out of the water for as long as 

 30 minutes. 



Further experience in hatching eggs in gravel resulted in the loss 

 of the entire lot involved in the experiment. When the hatching 



