94 U. S. BUREAU OF FISHERIES. 



It is quite plain that the salmon runs entering the Columbia River 

 and the Strait of Juan de Fuca can not long continue to exist under 

 this terrific drain upon the immature and mature fish. In the latter 

 section the sockeyes and humpbacks are rapidly being exterminated, 

 and it is probable that the chinooks and cohos, the especial victims in 

 this attack, will soon show signs of exhaustion. 



The State authorities appear to be helpless in these matters, but an 

 enactment by the Federal Government could be maintained, as the 

 principle has been applied to fishery matters elsewhere, notably the 

 spring mackerel closed season for five years and the sponge law relat- 

 ing to the landing of undersized sponges taken from the grounds off 

 the Florida coast. 



Next to the fishing operations of man, the gravest danger to the 

 salmon fisheries of the Pacific coast lies in the pollution of the rivers 

 which the salmon ascend for spawning purposes. The salmon, both 

 old and young, require pure cold water, and the immense runs which 

 have annually ascended the streams for many years are doubtless 

 due to the fact that such conditions have prevailed in them. The 

 large increase in the population of the coast States within recent 

 years, with the resulting increase of mills and factories, has greatly 

 increased the amount of sewage from cities and towns and the waste 

 of the manufacturing plants. Many of the latter have also con- 

 structed dams mthout adequate fishways, and these also wreak great 

 havoc to the industry by cutting the fish off from the upper reaches 

 of the rivers upon which constructed. 



The emptying of sewage into streams ought to be made a crime. 

 It is an exceedingly crude method of dealing with it, and, instead of 

 disposing of the filth, merely transfers it from one place to another, 

 making the water unfit for use at points farther downstream and 

 spreading diseases and death amongst not only the finny but also 

 human users of it. 



In the present condition of sanitary science it is a comparatively 

 easy matter to dispose of this filth by modern septic devices, and a 

 number of cities are now disposing of their sewage in this manner. 



The irrigation ditch, a comparatively new product on this coast, 

 while of great benefit in developing the arid lands in certain sections, 

 as at present operated is a considerable menace to the salmon fisheries. 

 But few ditches have screens at their head, and as a result many 

 thousands of young salmon slowly making their way to the ocean 

 home pass into and down these to an early doom. Every owner of 

 such a ditch should be compelled to place at its head a screen with 

 fine enough mesh to prevent absolutely the passage through the 

 same of even the tiniest baby salmon. 



Next to man and his methods the trout is undoubtedly one of the 

 greatest enemies of the salmon. The Dolly Varden follow the salmon 

 from the sea to the spawning beds, and when the eggs are extruded 

 devour countless thousands of them. Many and many a time the 

 "WTiter has seen on the spawning beds female red salmon swimming 

 around with a cloud of trout spread out behind like a fan, following 

 her ev<^ry movement, eagerly waiting for the moment when the eggs 

 shall appear. 



In the summer, when the young are heading for the sea, the trout 

 are lying in wait for them and again take their toll of countless 

 thousands. 



