A PERFECT FISH PASS 



Some suggestioyis as to Defects in Fish Passes and how 

 to Overcome Them. 



By Professor Edward E. Prince, LL.D., D.Sc, Ottawa. 



Canada, Dominion Commissione?' of Fisheries a7id 



Representative of Canada on the International 



Fisheries Commission under the Fishery 



Treatij of 1908. 



Fishery authorities are practically agreed that the 

 decline of salmon in most countries is due, more than 

 to any other cause, to the blocking of rivers and lakes 

 by dams, artificial barriers, etc. No one can doubt that 

 overfishing, injury to spawning beds and fifty other 

 unfavorable circumstances, have had small effect com- 

 pared with the completely destructive character of dams 

 and the like. Shad, alewives or gaspereaux, sea trout, 

 striped bass, and other valuable fish, have also become 

 practically extinct in many localities where they once 

 abounded, all from the same cause. 



FISH SECONDARY TO INDUSTRIES ON RIVERS. 



Lumber mills, electric power houses, grist and granite 

 work, pulp factories and other active enterprises, 

 which more or less vitally depend upon water-power, 

 have ruined some of the finest rivers in the world by 

 entirely blocking them with dams and huge barriers. 

 A lovely salmon river that was worth to the locality (in 

 Nova Scotia) probably $50,000 per annum, was ruined 

 a few years ago by the erection, not of one, but a series 

 of dams in connection with the wood pulp industry and 

 on a protest being raised, a prominent leader in the coun- 

 try replied, "$50,000 worth of fish must give way to 

 $5,000,000 worth of industry." 



INGENUITY AND NUMBER OF FISH PASSES. 



No wonder that to overcome this grave trouble, ingeni- 

 ous and zealous minds, in almost every civilized country. 



