46 Part III. — Twenty-sixth Annual Beport 



4. Proofs of Eesults. 



Although such theoretical considerations as are above stated have 

 sufficed for the continuance of the artificial propagation of sea fishes, and 

 on an increasing scale, it would clearly be of advantage if evidence of a 

 definite kind were forthcoming to prove the results of the work. It is 

 not doubted that in areas of water under more or less complete control, 

 within which the effects can be ascertained with comparative ease, pisci- 

 cultural operations may be beneficial and profitable. The great extension 

 of carp culture in ponds, as in Germany, is an illustration of what may 

 be accomplished in such circumstances. Oyster culture, where the condi- 

 tions can be to a large extent controlled and the results determined, is 

 another illustratiou relating to the sea. But where the areas are very 

 large, as in the great lakes of North America, or where rivers are con- 

 cerned, as in salmon culture, the conditions cannot be controlled in this 

 way, nor can the results be easily ascertained. In such cases it is 

 extremely difficult to separate the results due to natural causes, or due to 

 the action of other kinds of artificial interference, as fishery regulations, 

 from those caused by the liberation of large numbers of artificially-hatched 

 fry ; usually, indeed, the particulars which are necessary to come to a 

 definite conclusion are awanting. IS^otwithstanding the absence of 

 definite statistical evidence of this kind as to the amount of benefit 

 derived from piscicultural operations, it is to be noted that in almost all 

 countries the number of fish hatcheries and the money expended on fish 

 hatching are increasing year by year, which may at least be taken as a 

 proof that those responsible for the policy and for the expenditure are 

 satisfied that the results are beneficial. The Fish Commissioner of the 

 United States, in speaking of the general results of the piscicultural 

 operations, makes the following remarks: — "Encouraging results of the 

 efforts of the Government to maintain the fish supply by artificial means 

 appear in reports from fishermen and fish culturists in all parts of the 

 country. Although it is difficult to establish definitely the extent to 

 which the hatcheries have affected the condition of the commercial fish- 

 eries of the coastal waters and the Great Lakes, the renewed productive- 

 ness of old and abandoned fishing grounds and the abundance of fish on 

 entirely new areas are strongly indicative. Unusual numbers of cod are 

 reported all along the coast, and surprising catches ha^ e been made on 

 inshore grounds. In spite of the growing scarcity of adult lobsters and 

 the ruthless destruction of young and eggs during the last ten years, 

 fishermen on the New England coast have been finding in their traps 

 many more young lobsters than formerly ; flat-fish are much more 

 numerous, especially small flat-fish, in the shallow waters along shore ; 

 and exceptional catches of white-fish were made this year in Lake Ontario 

 and Lake Erie, which fishing firms operating there attribute wholly to 

 the planting of artificially-hatched fry." * In Canada, Professor Prince, 

 the Commissioner and General Inspector of Fisheries for the Dominion, 

 notes in his report on the fish-breeding operations in 1907 the existence 

 of the same views as to the benefit of the work. "Public opinion," he 

 says, "is indeed favourable in the highest degree to the expansion of artificial 

 fish-breeding in its various branches, and the federal government has not 

 been slow to recognise the desirability of extending hatchery operations." t 

 Another example of the sam.e policy — the recommendation of fish culture 

 as a means of increasing the supply, without exact statistical knowledge 



* Report of the Commissioner of Fisheries for the Fiscal Year ended June 30, 

 1906, p. 5. 



t Fortieth Annual Beport of the Department of Marine and Fisheries, 1907, pt 232. 



