Prince. — Irrigation Canals and Fisheries. 163 



fish," all producing tenacious eggs, usually in gummy masses, I 

 need say little. Their sporting qualities are inferior, and in 

 southerly areas they are soft and poor flavored. "Poisson mou" 

 they are called by French Canadians, and, as the term implies, 

 they are flabby and tasteless ; but in northern lakes and streams 

 they are firmer and sweeter than in eastern and southern regions. 

 In waters connected with the Hudson Bay basin I have found them 

 firm, white, and so well flavored as to compare favorably with any 

 other table fish. One species, the large Channel Cat (Ictalurus punc- 

 tatus), is worthy of special mention both for its fine edible qualities, 

 and for the sport it furnishes. It is a strong, powerful fish when 

 hooked ; but it is voracious, and like the whole Catfish family, some- 

 thing of a scavenger. 



BLACK BASS IN IRRIGATION RESERVOIRS. 



The black bass, when planted, may cause disappointment, 

 because of its inordinate voracity. It will devour its own young 

 if other small fish are not plentiful for food. Where few bass 

 could find sustenance a far greater number of yellow perch would 

 flourish. Black bass, of both species, nest in shallow water — 

 three to six feet deep — and shelves of concrete, or of sunken wood 

 covered with gravel would be necessary as nesting platforms. 

 Even yellow perch increase more favorably when such plat- 

 forms are provided, but they must slope from two to four feet, 

 and freezing in early spring, when the water may be low, is thus 

 guarded against. Pike perch or wall-eye pike are fine fish, but 

 must have shallow gravel areas, over which running water passes 

 to produce the best results. 



VARIOUS FORMS OF SCREENS FOR IRRIGATION DITCHES. 



Screens at the intake or inlet of all ditches and canals are 

 really essential, especially if there is any communication with 

 streams frequented by trout, as in the eastern foothills of the 

 Rockies. The complaint of a Canadian Fishery oflicer that "irri- 

 gation ditches are great cause of destruction. . . . but screening 

 is possible if properly done," (Canadian Alberta Commission 

 report 1910-11 p. 960) is a common one, though the red-throat 

 or cut-throat trout, if of any size, rarely perish ; but pike and 

 bull trout {Salvelinus malma) commonly do so, as well as many 

 small species of fish of little value. 



"I never saw trout in irrigation ditches, or trapped in pools 



