FISHERY BULLETIN: VOL. 74, NO. 4 



Table 9.-Summary of available data on fecundity of coho salmon throughout most of the geographic range.' The data are not strictly 

 comparable among the various published and unpublished sources because of differences in methodology. Localities arranged in 

 counterclockwise order from California to Sakhalin Island, USSR. 



Area 



Average 

 no. of 

 eggs 



No. of 



fisfi in 



sample 



Average 



fork length 



(cm) 



Source of data 



California: 



Scott Creek 

 Oregon: 



Fall Creek, Alsea River 



Big Creek 

 Washington: 



Minter Creek 



University of Washington, Seattle 

 British Columbia: 



Cowichan River, Vancouver Island 



Oliver Creek (tributary to 

 Cowichan River) 



Beadnell Creek (tributary to 

 Cowichan River) 



Sweltzer Creek 



Fraser River 



Nile Creek 



Namu Cannery 



Port John Creek 

 Alaska: 



Sashin Creek, southeastern 



Nakvassin Creek, southeastern 



Bear Creek, Cook Inlet 



Bear Creek, Cook Inlet 



Dairy Creek, Cook Inlet 



Cottonwood Creek, Cook Inlet 



Fish Creek, Cook Inlet 



Swanson River, Cook Inlet 



Lake Rose Tead, Kodiak Island 



Lake Miam, Kodiak Island 



Karluk River, Kodiak Island 

 Union of Soviet Socialist Republics: 



Kamchatka River, Kamchatka 



Bolyshaya River, Kamchatka 



Paratunka River, Kamchatka 

 Tyml River, Sakhalin Island 



22,616 



65 



366.3 



Shapovalov and Taft (1954) 



1973) 



'Table adapted from Rounsefell (1957) and Allen (1958). 



^Value calculated from regression curve. 



^Mean length determined from 338 females. 



■•Total length. 



^Three to eight specimens per year. 



'After introduction of Swanson River coho salmon stocks into Bear Lake. 



'Mideye to fork length. 



8Lengths given by Gribanov (1948), not from females sampled for fecundity. 



during daily stream surveys. Only seven spent 

 females were examined each year because high 

 water washed most dying spawners from the 

 stream. The number of eggs ranged from to 64 

 and averaged 8 per female for the two seasons. 

 Koski (1966) examined 30 spent female coho salm- 

 on in an Oregon stream and found an average of 

 four eggs per female. In streams of Kamchatka, 

 Semko (1954) found that coho salmon retained 

 0.3% of the actual fecundity (about 7 to 16 eggs per 

 female). 



JUVENILE COHO SALMON STUDIES 



With anadromous salmon, the result of fresh- 

 water production is a juvenile migrating to the 

 ocean-a smolt or fry physiologically adapted to 



enter salt water, where most growth takes place. 

 Our studies were designed to measure the yield of 

 coho salmon smolts and to determine some of the 

 factors that bear on this yield. We counted and 

 sampled the juvenile coho salmon at a weir as they 

 left Sashin Creek and entered the estuary, and 

 also sampled juveniles in the stream with seines. 

 In addition, after determining that many fry of 

 unknown physiological capabilities entered salt 

 water, we performed experiments to determine 

 the ability of these fry to survive the salinities 

 existing in the estuary. For studies in the stream 

 coho salmon juveniles were considered as two 

 groups-fry (age 0) and fingerlings (age I and 

 older). 



Specific topics considered here are: 1) the 

 numbers of coho salmon smolts and fry entering 



906 



