FISHERY INDUSTRIES. 29 



swimming stage. A hatchery can produce those 50,000,000 young 

 fish from 50,000 adults; therefore the other 50,000 adults maybe put 

 into cans and no diminution of the subsequent supply result. The 

 difference, then, between this 50,000 fish required by the hatchery 

 and the number required to spawn on the natural beds to maintain 

 the supply represents the value of the hatchery. Assume that the 

 number required to spawn naturally is 75,000; then the hatchery has 

 saved 25,000 fish, which at 20 cents each are worth S5,000. This is 

 the real value of the hatchery's work. 



It must not be lost sight of that the margin of raw material ren- 

 dered available by the hatchery may be of much greater comparative 

 value than the original margm of equal number above the require- 

 ments for natural propagation. For example, in the case cited, the 

 first 25,000 fish, the available excess above natural spawning require- 

 ments, may just fail to meet the cost of conversion into a commercial 

 product, in which case no commercial use could be made of them at 

 all. Whereas, by the added 25,000 available under the hatchery 

 system, the additional cost of operation may be met and a substantial 

 profit made. Again, it must be remembered that with experience 

 more certainty may be introduced into the business under a controlled 

 and known system of propagation, and anything which tends to 

 remove the speculative element tends to reduce cost of operation. 

 These figures are merely hypothetical, and without statistics not 

 now available real values can not be estimated. The only purpose 

 of the computation is to illustrate the fallacy of regarding the opera- 

 tion of hatcheries as the sole or even as the necessarily best means of 

 maintaining the salmon fishery. 



As a commercial proposition it might be better to curtail the pack 

 and permit a large spawning escape than to make the maximum 

 pack and exhaust even a portion of the increased gross receipts in 

 maintenance of the supply of raw material. 



MARKED SALMON. 



An unusual number of "marked" salmon were taken during the 

 season at the Fortmann and Yes Bay hatcheries. At Yes Bay the 

 superintendent reports taking 28 females and 13 males with both 

 ventrals missing, and 6 females and 4 males with one ventral gone. 

 He adds that he believes had the examination of the males in the 

 course of spawning been as thorough as of the females, there would 

 have been as many males as females noted. About a dozen of these 

 marked fish were reported from the Fortmann hatchery at Loring up 

 to the end of October. An examination of the scales of these fish 

 shows them to be of the ordinary type. Examples from three indi- 

 viduals were examined, a female from Loruig and a male and a female 

 from Yes Bay. All appear to be 4-year fish. There is always a 



