PLANTING EYED SALMON AND TROUT EGGS. 



By C. W. Harrison, 

 District Inspector of Hatcheries for British Columbia, 

 Vancouver, B. C. 



For many years fish culturists have been attempting to 

 devise ways of planting, in their natural environment, the 

 eggs of fish artificially spawned. Particularly this has been 

 the case with salmon and trout eggs, and though several 

 methods have been tried, they have not met with unquali- 

 fied success : the faults in them have been obvious to those 

 engaged in the propagation of fish life. 



One of the methods employed, particularly in Great 

 Britain, has been the screening off of sections of natural 

 spawning grounds and then scattering the eggs in these 

 enclosed areas. But the loss through exposure to sunlight, 

 natural enemies and through eggs which failed to lodge in 

 crevasses in these partly protected areas being washed 

 down stream, made popular acceptance of this method im- 

 possible. Another method was to construct boxes in the 

 streams and place therein layers of gravel and eggs through 

 which the necessary amount of water was allowed to circu- 

 late. This system, though successful in hatching the eggs, 

 was so limited in its application that the wide distribution 

 of ova — at which egg planting principally aims — was far 

 beyond its scope. 



The m.ethod described below has overcome all obiec- 

 tionable features which apply to these artifices mentioned 

 and has for three years been employed in British Columbia 

 by the Department of Marine and Fisheries of Canada with 

 a large degree of success. 



Three years ago it was found necessary for the writer to 

 proceed to an unsettled and isolated portion of the northern 

 British Columbia Coast with a view to rehabilitating certain 

 streams which had become depleted of sockeye salmon and 

 to use for this purpose eyed sockeye eggs which were to be 

 planted in gravel under as natural conditions as possible. 

 The district to be seeded was many miles from a settlement 

 and conditions demanded that a speedy and inexpensive 

 m-eans of distribution be employed. Planting in gravel on 

 the natural spawning grounds was the only way open and 

 although this work had been attempted before by various 

 means, on an experimental scale, the nature of the district 

 and the shortage of local material precluded the use of any 



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