scholarly journals Ⅱ-2. Status of chum salmon stock in Hokkaido

2018 ◽  
Vol 84 (5) ◽  
pp. 924-924
Author(s):  
YASUYUKI MIYAKOSHI
Keyword(s):  
1982 ◽  
Vol 60 (6) ◽  
pp. 1463-1469 ◽  
Author(s):  
Terry D. Beacham

Significant regional and annual variability in fecundity of coho salmon (Oncorhynchus kisutch) and chum salmon (O. keta) in British Columbia was detected during this investigation. A Kodiak Island (Alaska) coho salmon stock was more fecund than southern stocks in British Columbia and Washington. Fecundity ranged from 2450 to 2850 eggs per female at 53.6 cm postorbital–hypural length for Vancouver Island stocks to over 4400 eggs per female for a Kodiak Island stock at the same length. Chum stocks on Vancouver Island and the Queen Charlotte Islands generally had fecundities less than 3200 eggs per female at 58.8 cm postorbital–hypural length, whereas chum of equal lengths in mainland British Columbia stocks ranged from 3200 to 3450 eggs per female. Older chum and coho were usually more fecund than younger ones, but this difference could be accounted for by differences in mean length-at-age, fecundity being related to body size.


1983 ◽  
Vol 40 (11) ◽  
pp. 1880-1886 ◽  
Author(s):  
B. A. McCarl ◽  
R. B. Rettig

Regression studies of salmon stock-recruitment relations require a priori assumptions concerning the nature of stock variability as influenced by smolt populations. Such assumptions can lead to biased estimates of the relationships of smolts to the production of adult salmon. This paper utilizes a statistical method which allows the data to determine the interrelationship of smolts and adult production mean and variability without imposing a priori restrictions on the form of such. The estimation process yields two estimated relationships — one explaining the effect of hatchery releases on expected adult production and another explaining the effects of the hatchery releases on the standard deviation of adult production. Application of this model suggests that the standard deviation of adult production increases with the square of the number of seaward migrants both for Hokkaido chum salmon (Oncorhynchus keta) and for Oregon coho salmon (O. kisutch) and that incorrect inferences may have been obtained about density dependence by other authors because of the imposed a priori assumptions and/or data adequacy.


Author(s):  
Dave E. Schuett-Hames ◽  
N. Phil Peterson ◽  
Robert Conrad ◽  
Thomas P. Quinn

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