4 TROUT-FISHING FOR THE BEGINNER 



invariably go down at the same time as 

 their wives, but often remain not far from 

 the spawning grounds, descending to deep 

 water at a later period. 



Roughly speaking, the ova lie for some 

 three months in the gravel, according to 

 the temperature of the water. Prior to the 

 birth of the alevins, as the newly hatched 

 troutlets are called, these eggs go through a 

 precarious existence. Not only do water- 

 fowl, rats, eels, insects and larvae feed upon 

 them when they can, but both young trout 

 and late-spawning fish greedily devour them. 

 Some ova may be buried by floods which 

 wash up tons of gravel, or the water may 

 freeze solid in winter, which means that the 

 eggs are crushed beneath the ice. Only a 

 small percentage of the eggs hatch, which is 

 not surprising when we consider the exigen- 

 cies of their surroundings. 



When first they see the light, the alevins 

 are not fond of it, and so bury themselves 

 in the gravel. Later on, however, they 

 begin to bestir themselves, hiding behind 

 the stones. Here again they run the gauntlet 

 of their enemies the eels, larvae, caddis- 

 worms and so on, and their ranks are still 

 further reduced. Until some weeks old, each 

 alevin is provided with a yolk sac, from 



