Breder. — Marine Fish Culture. 215 



the scrods is probably near 1^ pounds. From this we may 

 broadly say that about 3,490,962 adult cod and 657,472 scrod were 

 landed in 1921. By simple calculations according to this reason- 

 ing one large cod in every lot of 13,375 would be a hatchery fish 

 as would one scrod in every lot of 13,148. These smaller fish 

 would naturally be expected to be of a later year's work, but as 

 approximately a like number would be taken from the group 

 which form this year the large and market fish a season before, 

 the figures may stand as being reasonably correct. This would 

 give a grand total of 4,003 pounds of cod, or less than .008 of 

 one per cent of the total catch for the year as hatchery fish. On 

 the face of it, it is obvious that these calculations are absurdly 

 liberal to the hatchery fish, for it is assumed that the fishermen 

 hailing from these three major ports would be the only ones to 

 catch these fish and that they would catch all of them, that is 

 take 16 per cent as scrod one year and the remainder the follow- 

 ing. A long list of further reasons why this is a high figure 

 might be given but it would be superfluous for our purpose here. 

 Any one, with the figures available, might calculate the cost 

 per pound of a j'-ear's output of hatchery cod which is certainly 

 composed of considerably less than 311 individuals made availa- 

 ble to the fishermen by this method, and compare it with the 

 actual value of this amount of fish. Neglecting the Norwegian 

 method which takes fish which would not have necessarily been 

 caught otherwise, and granting that all of the fish stripped would 

 have died anyway, can it be said that this amount of codfish is 

 worth the money, time, and energy expended? It is pointed out 

 finally that this number, 311, is perfectly absurd because at every 

 step the calculations have purposely been placed way out of the 

 reach of even extraordinary success just to show that even then 

 no important effect could be expected. A very minute fraction 

 of this .008 of one per cent is all that could actually be obtained in 

 practice. ^ 



1 Data and assumptions on which calculations were based: Cod reach 

 maturity usually in about the fourth year. They are then generally about two 

 feet long and weigh over six pounds. A 25-pound fish may lay 2,700,000 eggs 

 and a 75-pound one 9,100,000. A 6%-pound fish lays on the average of about 

 1,500,000 eggs. It was assumed that this is the average of all spawners. The 

 number of fry 77,659,000 liberated at Woods Hole in 1917 was doubled (155,- 

 318,000) because of the assumption that they had twice the advantage of the 

 wild fry. 



Three flsh per female are supposed to attain "maturity": Then 3 : 1,500,- 



