FISHWAYS IN BRITISH COLUMBIA 5 



stream migration, from March to September, of two distinct ages and 

 sizes of young salmon. ■ ' 



There are therefore, two main features to the problem of safe-i 

 guarding the fishing interests in connection with, construction work 

 for power or other development on the rivers of British Columbia. 

 First, it is necessary to permit a sufll^cient number of adult salmon 

 satisfactorily to pass all obstructions in order to reach and deposit 

 their ova upon the spawning beds of the streams; and, second, to 

 ensure that the young salmon are afforded a satisfactory passage- 

 way out to the sea. 



Practically all the adult salmon which ascend the streams to 

 spawn consist of fish of four or five years of age.* That is to say: the 

 fish which are hatched in one year do not re-ascend the stream to 

 spawn until four or five years later. Consequently, it is not possible 

 to evaluate the effects of an obstruction in a salmon stream until the 

 period for return has elapsed. 



Two specific instances of interference with the salmon run may 

 be here considered. 



One of the largest tributaries to the Preiser, and one of the chief 

 salmon streams, is the Quesnel river. Quesnel lake, with its tribu- 

 taries, comprises about twenty-five per cent of the entire spawning 

 area of the Fraser river. Every four years on the Fraser river occurs 

 what is known as the 'big year' run. This took place in 1897, 1901, 

 1905, 1909 and 1913, and, in the normal course of events, would have 

 been expected in 1917. 



In 1895, the province granted to a mining company the right to 

 construct a dam at the outlet of the Quesnel lake, but no provision 

 was made for the passage of the salmon through the dam. The result 

 was that, following the completion of the dam in 1898, the salmon 

 were denied access to the spawning grounds of Quesnel lake, and, 

 without having spawned, perished in countless thousands in the river 

 below. Sufficient gold was not found to warrant a continuance of 

 mining operations, and hence the gates, which had been closed for a 



* The proportion of four and five-year-old fish varies between very wide limits. 

 On the Fraser river, which is the only large stream of the Province possessing a race 

 of sockeye which mature principally in their fourth year, about 80 per cent, on an 

 average, are four-year-old fish. This figure is based on investigation extending over 

 some years. On some other rivers the proportion of five-year-old fish exceeds that 

 of four-year-old fish. Interesting details of these investigations are given in the 

 Annual Reports of the Commissioner of Fisheries, British Columbia. 



