No significant number of chinooks passed the weir during any of 

 these years, and it is doubtful that a large number of this species 

 ever passed through Lake Osoyoos and spavmed above it. 



From 1939 to 1943 inclusive, any anadromcus fish which might 

 have entered the Okanogan vfere trapped at Rock Island Darn. Many 

 of the blue backs were hauled by tank truck to Lake Osoyoos, but 

 the chinooks were all placed in other stream systems. This was 

 in accordance with the program of the Grand Coulee Fish Main- 

 tenance Project necessitated by the construction of Grand Coulee 

 Dam. 



Because of the high water temperature and the slight gradient 

 there are a large number and variety of rough fish in the river 

 below Lake Osoyoos. Squawfish ( Ptychocheilus oregonensis) , carp 

 (Cyprinus carpio), bream (Richards onius balteatus), large -mouth 

 black bass (Aplites salmoides ), and several species of suckers, 

 chubs, whitefish, and "catfish are all found in varying abundance 

 in the stream. 



Lake Osoyoos also has a number of resident fishes. Large- 

 mouth black bass, yellovj perch ( Perca flavescens ), ling ( Lota 

 maculosa), kokanee or silver trout ( Oncorhynchus nerka kennerlyi ), 

 and carp are all common. Some kamloops trout [s'alno gairdnerii 

 kamloops) are taken in this lake, but they are not abundant. 



In the stream sections between the various lakes in the 

 Canadian portion of the river system there appear to be few 

 resident fish except carp and suckers. Trout are not abundant 

 in the main stream. 



Lake Okanogan contains kamloops trout, kokanee or silver 

 trout. Rocky Mountain and eastern whitefish, and a groat variety 

 of rough fish such as sauawfish, carp, and suckers. Lakes Skaha 

 and Vaseaux also have kamloops trout and landlocked bluebacks, 

 as well as rough and spiny rayed fish. 



At the present time the Okanogan 'River has the greatest 

 available, and potentially available habitat for blueback salmon 

 in the entire Columbia Ri^'er System. Blueback now utilize Lake 

 Osoyoos and some 8 miles of the river immediately above the lake 

 for rearing and spawning area. The construction of fishways at 

 the Lake Vaseaux diversion dam and at certain falls upstream 

 would make available considerably more area for the natural 

 propagation of this species. 



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