62 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



E.— Their dangers and fatalities. 



A general account of the fisheries of the North Atlantic coast of the 

 United States is not to be completed without some mention of the 

 agencies by which they are affected and reduced in abundance other 

 than as the result of age. The variet} 7 of such influences is very great; 

 perhaps more than in the case of the terrestrial vertebrates, and com- 

 parable only to the affections and influences upon insects, which, like 

 the fishes, occur in overwhelming abundance at one time to be more 

 than decimated at another. 



We may consider the subject of the dangers and fatalities under 

 three heads : first, those brought about by their fellow-inhabitants of 

 the sea ; second, by man ; and, third, by natural or physical causes and 

 changes. 



1. FROM OTHER FORMS OF MARINE LIFE. 



The injuries caused by their fellow-inhabitants are twofold in their ac- 

 tion : first, upon the eggs and embryonic fish, and second, upon the more 

 fully grown fish. The destruction of the eggs of fishes is something 

 truly enormous, the percentage of the yield of even the youngest fish 

 from a given number of eggs being extremely small. It has been cal- 

 culated, in the case of the salmon or shad, that not five eggs out of one 

 thousand produce young fish, able to commence feeding, all the rest 

 being destroyed in one way or another. . It is quite likely that even this 

 ratio is too large. A part of this loss of eggs is due, however, to im- 

 perfect fertilization, and it is here that artificial propagation has the 

 advantage in securing the contact of the milt with all the ripe eggs, 

 leaving an insignificant fraction not fertilized. Probably not half, and 

 sometimes even much less than half, the eggs discharged experience the 

 same fortune in natural spawning. It would seem as if the immense 

 disproportion of eggs to the resulting fish was an intentional provision 

 in nature, to furnish food to the small inhabitants of the sea, especially 

 to the young fish themselves, of various species, no other bait being so at- 

 tractive to fish, even to those that have just laid the' very eggs used for 

 this purpose. The size of the eggs varies very greatly with the species, 

 as will be seen in a subsequent chapter, some being adapted to the 

 smallest mouth, others requiring one of considerable capacity to take 

 them in. There is almost no season of the year when fish eggs cannot be 

 found in the water, either floating free or else adherent to some object, 

 and the work of devouring them is carried on continually. Of course 

 it is only the smaller fishes that pick up the small eggs ; but theformer, 

 in turn, contribute to some of larger size, and those to larger again, 

 until finally, -in the sequence, the largest inhabitants of the sea obtain 

 their proper food. 



It is among the aquatic mammals that we find the most powerful de- 

 stroyers of fish, these requiring a much larger amount in proportion 



