DISTRIBUTION. 



i 9 i 



vent pollution. Already we know that trout 

 ova do not hatch well in polluted water, and 

 now there is some foundation for the belief 

 that it is more or less fatal to the Mayfly, 

 the best of all food for large trout. As might 

 well be expected, the fly being more plentiful 

 in these by-streams, trout are inclined to work 

 up into them immediately before the hatch of 

 Mayfly. 



In a water meadow country trout will find 

 their way into the carriers when full of water, 

 and as the level is drawn down they congregate 

 in hatch holes and other deep parts of these 

 smaller streams. Sometimes the result of this 

 is that they are too plentiful for the supply of 

 food, and, as a natural sequence, they go back 

 both in condition and colour. Generally, 

 throughout a stream there is a tendency for 

 trout to work up until they arrive at a hatch, or 

 some other obstruction, when, except in a very 

 high water, they often settle down, and take up 

 their habitation in the depths of the nearest 

 hatch hole. 



Fear of their enemies does not appear to be 

 as potent a factor in influencing the movements 

 of fish as the other instincts before alluded to. 

 A reach of deep and comparatively still water in 

 a stream fully stocked with pike of various sizes 

 usually contains a few large trout, and although 



Tendency to 

 congregate in 

 hatch holes. 



Fear of 

 enemies. 



