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of tlie species ; for the number of eggs produced by a female salmon at one spawning 

 season is very large. But as a matter of fact the regulations are not enforced 

 in this way : the salmon ascend rivers throughout the summer, and do not spawn 

 till autumn, and the fish that have recently spawned are of no value. Those that 

 are sought are those that have just entered the river. The annual close season 

 is limited to the actual spawning period. In consequence it is only those adults 

 which escape the net, the hook, and the trap which survive to deposit their eggs and 

 milt. However, even thus the close season has a good efiect, for it ensures that the 

 adults who do escape shall shed their reproductive products in peace and security, and 

 the eggs are therefore all fertilised and placed in conditions proper for development, 

 while if the fish were disturbed, a greater number would be destroyed, and the eggs 

 of those that were left would not be so properly deposited. 



But another method which has been appUed to anadromous fish is that of artificial 

 propagation. This has been successful chiefly in the case of SalmonidEe and of the 

 American shad, Alosa sapidissima. It seems to me that the application of this measure 

 deserves to be considered carefully. Let us suppose a river visited regularly by salmon 

 for the purpose of spawning. If during the close season pisciculturists are permitted 

 to catch a number of the spawning salmon in the river, strip them of their eggs and 

 milt and hatch them in the most perfectly arranged hatchery, and then turn the fry at 

 a certain stage again into the river, what will be the result ? If a greater percentage 

 of eggs can be hatched under artificial conditions than under the natural, then of 

 course the result will be to increase the number of fry produced in the river. 



This may be the case supposing that the eggs are preyed upon by other fishes or 

 animals in the natural state, from which they are of course protected in the hatchery. 

 But it would be equally effective to leave the eggs in the natural state and destroy 

 their enemies. The artificially hatched fry are returned to the river soon after 

 hatching, so that they are protected for a very short time, which, however, may be an 

 advantage if in the natural state they are devoured in numbers when first hatched. Of 

 course all this only applies to the case supposed. When artificially fertilised eggs or 

 hatched fty, derived from other places, are put into a river, they will of course add to 

 the salmon population of the river if the conditions necessary for their life prevail in 

 that river. 



Considering now the case of the American shad, we find the problem different. The 

 estuaries, when the American Fish Commission commenced operations, were over fished, 

 and some had been entirely depopulated. There was no close season for shad, in fact it 

 was scarcely possible to institute one, for the shad unlike the salmon enters the river 

 only a very short time before it actually spawns, and the immense majority of 

 individuals captured are, like the herrings taken in Britain, either actually ripe or 

 very nearly so. Hence a close season would have meant prohibiting the fishing- 

 altogether. Such numbers of shad were taken for many years, that the number of 

 eggs deposited was not nearly sufficient to keep up the numbers of the species. Nearly 



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