were observed during the survey in July, when nearly the entire 

 length of the reservoir was visited by us over a period of 10 days. 



Generally speaking the consensus of opinion of sportsmen in- 

 terviewed was that: (1) sport fishing has been on the decline during 

 the last ten years (2) Grand Coulee Dam has contributed to this de- 

 cline, and (3) scrap fish have become a nuisance* 



Relative Size of Fish Populations 



Gill net fishing has been done at Cultus Lake in British 

 Columbia to reduce the nxomber of predaceous fish (Foerster and 

 Rioker, 1942), 8md information on the fish population obtained 

 there is of interest for comparison with tiie Roosevelt Lake data* 

 Because the sguawfish was the most abundant species gill netted in 

 both lakes, a comparison of the catches of that species was made; 

 results are given in Table 10* 



It is seen from Table 10 that in 1935 Cultus Lake nets yielded 

 11*2 squawfish per net night as compared with 4*9 for Roosevelt Lake 

 in 1948 (1935 data are used for comparison because the abundance of 

 squawfish was presximably reduced after that year as a result of the 

 predator control progreun)* Since the nets at Cultus Lake were 1*2 

 times longer than the Roosevelt Lake nets, the Cultus nets can be 

 expected to have 1*2 times better opportunity of catching fish* The 

 catch at Cultus was 2.3 times as great as that at Roosevelt Lake, 

 but if the larger net size at Cultus Lake is taken into consideration 

 the catch of squawfish actually was only 1*9 times greater for Cultus Lake* 



The predator control work in Cultus Lake was carried on especially 

 for the purpose of reducing the number of squawfish, which are extremely 

 predaceous on yoimg salmon* Squawfish were taken in largest numbers 

 during the months of April, May, June and early July, in nets set near 

 shore* During this period the fish were spawning on the gravel beaches 

 where the nets were set* During most of July, August, and early September, 

 poor catches were made, by all types of gear* After mid-September, fish 

 were caught in fair numbers in nets set on the bottom off shore, eoid 

 as the season prof^ressed they were taken in greater numbers in the deeper 

 waters of the lake* 



Fishing at Roosevelt Lake, on the other hand, was not done 

 specifically to catch squawfish but to get a representative sample 

 of the fish population* The nets were set at various depths and 

 locations but usually not near the shore where the squawfish were 

 more likely to be numerous* Also, the time fished was not during 

 the spring spawning as at Cultus Lake, but during the summer* When 

 all of the above factors are considered it seems probable that the 



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