THE HATCHING AND PROPAGATION OF FISH 7 



many thousands. To illustrate, it is well to note that 

 a salmon of 20 pounds will average about 16,000 

 eggs ; a 5-pound ouananiche, 4,000 ; a 2- to 4-pound 

 rainbow trout, 3,000 ; the brook trout averaging 

 somewhat less. The lake trout is estimated to yield 

 1,000 eggs to each pound of its weight ; a 2-pound 

 black bass will range from 2,000 to 10,000, the large- 

 mouth variety averaging more. When ripe, the eggs 

 are deposited upon the spawning beds, which vary in 

 location with the nature of the various fish. It can 

 be given as a general rule, however, that a gravel or 

 stony bottom usually forms the bed, although grass 

 and weeds are selected by some varieties. Many fish 

 seek shallow running water for their hatching ground ; 

 others, quite deep waters in lakes and ponds. Many 

 eggs are imperfect or undeveloped, or not milted 

 upon by the male fish. 



From the moment the eggs are being dropped 

 the many enemies of the fish commence their attacks, 

 and it really seems strange that a single one should 

 ever hatch out or attain its growth. So-called bot- 

 tom fish, comprising bullheads, suckers, and carp, are 

 the greatest destroyers of eggs. The bullhead and 

 carp live exclusively upon spawn during the season, 

 and devour it in such quantities that they have often 

 been taken so completely filled as to be absolutely 

 unable to move. It is a great pity that the carp was 



