SALMON FISHERY. 59 



fish are placed in the river, and go to and return from 

 the sea (during which time we obtain our relative pro- 

 portions of marketable fish from both sources), the 

 question arises from which system have we derived 

 the largest quantity at the least relative cost, com- 

 mercially. 



The 20,000 fish annually caught may vary in size, 

 from 6 to 30 Ibs. each. That various fish produce 

 various numbers of ova, I have no doubt ; as I found 

 one of 20 Ibs. in weight to contain 26,636 ova, whilst 

 another of 14 Ibs. only contained 6,890 ova; taking 

 the largest and smallest, we will assume that 20,000 

 fish had visited their breeding-ground the previous 

 year, and that one-half were females, and had pro- 

 duced 7,000 eggs each ; that is, that 70 millions of 

 eggs had been left in the rivers annually, and had 

 produced one marketable fish to every 3,500 ova de- 

 posited. This large quantity of 70 millions of fish 

 eggs annually deposited in a river, whose produce of 

 marketable salmon only amounts to 20,000 fish, ap- 

 pears to be a very extraordinary estimate, and leads 

 one to consider what becomes of the surplus, when 

 we find only one in 3,500 of the eggs, deposited natu- 

 rally, produces one fish that is ever caught, or be- 

 comes the food of man. 



I shall next compare this with the largest number 

 of ova that we ever deposited in hatching-troughs in 

 any one year, viz., 659,000 ; what number of market- 

 able fish would this number of ova give us, at 3,500 

 ova to each fish ? The answer would be, by the above 

 rule, 188 salmon. These at an average weight of 

 7 Ibs., at Is. per lb., would be worth 65: 16s. 



