236 American Fisheries Society 



The records for the fishing grounds show that the runs 

 of sockeyes to the Fraser River system in the big years 1901, 

 1905, 1909, and 1913 produced an average pack of 1,927,602 

 cases, and that in 1917, the last year in the cycle of big years, 

 it produced a pack of but 559,732 cases, or 70 per cent less 

 than the average of the four preceding big years. The start- 

 ling decrease in 1917 is due to the fact that the great runs of 

 1913 did not reach the spawning beds of the upper section of 

 the Fraser basin, for the reason that the river's channel at 

 Hell's Gate was blocked by a great slide of rock following the 

 construction of the Canadian Northern Pacific Railway through 

 the canyon of the Fraser. A tunnel was driven through the 

 rock cliff that overhangs the narrow channel immediately 

 above Hell's Gate. During the spring of 1913 the action of 

 frost caused a section of that cliff, including a portion of the 

 tunnel, to slide into the river's channel, which formed an ob- 

 struction that the main portion of the run of fish could not get 

 over. After frantic and continued efforts to surmount the 

 obstruction the fish became exhausted and were swept down- 

 stream by the rapid current, where they died in the channels 

 below without having spawned. 



The British Columbia Fisheries Report for 1913 states 

 that the number of sockeyes that escaped capture on the fishing 

 grounds, and that later reached Hell's Gate that year, was 

 fully as great, if not greater, than in the four preceding big 

 years. The condition at the principal spawning beds of the 

 Fraser created by the obstruction is described in the following 

 excerpt from an article by the author, in the British Colum- 

 bia Fisheries Report for 1913: 



I feel fully justified from my investigations in concluding that the 

 number of sockeyes which passed above the fishing limits was as great 

 this year as any preceding big year of which we have a record, and I 

 think even greater. The sockeyes made their appearance in the canyon 

 above Yale in June, and during the high waters of that month and July 

 large numbers passed through to Quesnel and Chilko lakes. The greater 

 proportion of the run of sockeyes in late July, and in August and 

 September, was blockaded in the canyon by rock obstructions placed in 



