On Slocking. 57 



the outlet of the redd, as the object is to permit 

 the young fry to find their way into the stream 

 under as nearly the same conditions as if hatched 

 in it as possible, but a loose wall of coarse gravel 

 and small stones forms no impediment to the 

 alevins passing out, and affords some protection. 



The quantity of Ova hatched out in redds proxi- 

 mate to any given fry-ground in the stream or 

 river must be adjusted, not only to the extent 

 of fry-ground and the probable amount of feeding, 

 but a full allowance should be made for the 

 amount of natural fry from the adjacent spawning- 

 beds, and this only local knowledge can estimate. 

 However, the artificially incubated Ova from the 

 redds will usually, but not always, have several 

 weeks start of the natural fry, and be able to 

 hold their own in the struggle for sustenance. 



REDDS will not take the place of stocking by 

 yearlings or by older trout, but in most waters 

 they will form a valuable adjunct to such stocking. 



PONDS. 



The general principles which govern the con- 

 struction of ponds, are : shade, food, control, 

 facility for emptying, and water supply. 



Shade is the first requisite, and may be 

 given by artificial shade ; by position, as proxi- 

 mation to natural shades from trees, banks, 



