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AMERICAN CREEK 

 n=678 



GR0SVEN0R LAKE BEACHES 

 n=85 



Pv3 tV: 



HARDSCRABBLE CREEK 

 n=l46 



nn 



GR0SVEN0R RIVER 

 n = 94 



rrrm 



NAKNEK RIVER SAMPLES 

 WEIGHTED 



AGE GROUP 



2 3 



Ifresh-water 



AGE 



2 3 



OCEAN AGE 



Figure 11. — Percent composition of sockeye salmon 

 escapement for American Creek (Coville Lake) and three 

 major spawning areas of Grosvenor Lake compared with 

 overall Naknek system escapement, by age group and 

 fresh-water and ocean age, 1962. 



age on the major spawning grounds of the Naknek 

 River system. 



Most spawning ground samples contained a 

 considerably higher proportion of the 5 3 age 

 group and a lower proportion of the 5 2 group 

 than did the trunk river samples. Only the Iliuk 

 Arm, Grosvenor Lake beach, and American Creek 

 samples contained a proportion of the 5 2 group 

 approaching that of the river samples. It is 

 notable that the samples from these three areas 

 also contained almost twice the proportion of the 

 6 3 age group as did the river samples. Ocean-age 

 samples from these three areas were characterized 

 by predominantly 3-ocean fish in 1962. Prac- 

 tically all other spawning ground samples con- 

 tained predominantly 2-ocean fish, many of them 

 with twice the proportion that occurred in the 

 river samples. 



Fresh-water age samples from most areas con- 

 tained a considerably smaller proportion of 2- 



Table 8. — Numbers of fish in dominant age groups in 

 sockeye salmon samples taken from the major spawning 

 grounds of the Naknek River system, 1962 



fresh-water fish than did the Naknek River 

 samples. Only the samples from stream N23.4 

 (9 fish) and the sample taken at the outlet of 

 Naknek Lake (80 fish) (table 7) had greater pro- 

 portions of 2-fresh-water fish. For the Naknek 

 Lake spawning grounds as a whole there was a 

 lack of 2-fresh-water fish, primarily because of 

 the absence of the 5 2 age group. 



Discussion 



The absence of the 5 2 age group suggests in- 

 adequate sampling of the total Naknek escape- 

 ment on the spawning grounds. All known 

 spawning grounds were surveyed and sampled in 

 1962, but only about half of the total escapement 

 counted on the Naknek River could be accounted 

 for on the spawning grounds surveyed. It seems 

 likely that some major spawning areas were not 

 sampled and that these areas could have contained 

 a high proportion of the 5 2 age group that was so 

 prevalent in the river samples. 



Until 1962 the Iliuk Arm beach area of Naknek 

 Lake was not regarded as a probable spawning 

 ground. During the 1962 stream surveys in this 

 area, however, survey crews noted large numbers 

 of fish jumping along a 1} 2 - to 2-mile stretch of 

 the southeast shoreline. These fish were present 

 after most of the tributary stream spawning had 

 been completed, but because of the turbid water, 

 we could not definitely establish whether these 

 fish actually spawned in this area nor could we 

 estimate their number. Evidence suggests, how- 

 ever, that they spawned in the beach area. 

 Subsequent sampling of these fish showed that 

 they were composed of a greater proportion of the 

 5 2 age group than most of the other spawning 

 grounds sampled. It is likely that this population 



476 



U.S. FISH AND WILDLIFE SERVICK 



