Change in chum salmon (Oncorhynchus keta) stomach contents associated with fluctuation of pink salmon (O. gorbuscha) abundance in the central subarctic Pacific and Bering Sea

1996 ◽  
Vol 5 (2) ◽  
pp. 89-99 ◽  
Author(s):  
KAZUAKI TADOKORO ◽  
YUKIMASA ISHIDA ◽  
NANCY D. DAVIS ◽  
SHOJI UEYANAGI ◽  
TAKASHIGE SUGIMOTO
Keyword(s):  
Bering Sea ◽  
Chum Salmon ◽  
Pink Salmon ◽  
Stomach Contents ◽  
Oncorhynchus Keta ◽  
Subarctic Pacific ◽  
Chum Salmon Oncorhynchus Keta

Estimating target strength of young chum salmon (Oncorhynchus keta)

2022 ◽  
pp. 1-5
Author(s):  
Kenji Minami ◽  
Hokuto Shirakawa ◽  
Yohei Kawauchi ◽  
Huamei Shao ◽  
Makoto Tomiyasu ◽  
...  
Keyword(s):  
Bering Sea ◽  
Chum Salmon ◽  
Fork Length ◽  
Target Strength ◽  
Oncorhynchus Keta ◽  
Biomass Estimation ◽  
Fishery Resource ◽  
Chum Salmon Oncorhynchus Keta ◽  
Acoustic Methods ◽  
The Bering Sea

Although chum salmon (Oncorhynchus keta) is an important fishery resource in Japan, acoustic methods cannot be applied to biomass estimation because the target strength (TS) is unknown. This study clarified the TS for each fork length (FL: 5.5–33.5 cm) of young chum salmon inhabiting the Japanese coastal area to the Bering Sea by measuring free-swimming fish. The size dependences of the TS values were TSmean = 20 log10 FL – 68.0, for both 38 and 120 kHz. This facilitated the estimation of biomass of young salmon using acoustic methods.

Genetic Effect on the Dynamics of a Model of Pink (Oncorhynchus gorbuscha) and Chum (O. keta) Salmon

1984 ◽  
Vol 41 (10) ◽  
pp. 1446-1453 ◽  
Author(s):  
William W. Smoker
Keyword(s):  
Chum Salmon ◽  
Pink Salmon ◽  
Genetic Effect ◽  
Genetic Mechanism ◽  
Oncorhynchus Gorbuscha ◽  
Oncorhynchus Keta ◽  
Chum Salmon Oncorhynchus Keta ◽  
High Heritability ◽  
Maturation Age

Different stock dynamics result from genetic and nongenetic mechanisms of determination of maturation age of chum salmon (Oncorhynchus keta) in a model of interacting pink (O. gorbuscha) and chum salmon stocks. When the model is disturbed from equilibrium by low survival in one pink salmon line, the genetic mechanism (high heritability of maturation age) leads to biennial cycles of numbers of even-aged chums and of numbers of pinks, similar to observed cycles. The nongenetic mechanism (zero heritability of maturation age) results in a new equlibrium at which neither stock cycles. When one pink salmon line is completely removed the genetic mechanism leads to biennial cycles of abundance of even-aged chums; the nongenetic mechanism does not lead to such cycles. These effects persist at intermediate values of heritability of maturation age and in spite of stochastic variability. The model is an adaptation of the Ricker curve to two interacting stocks, the recruitment for each depending on the density of both.

Early Marine Mortality of Marked Juvenile Chum Salmon (Oncorhynchus keta) Released into Hood Canal, Puget Sound, Washington, in 1980

1983 ◽  
Vol 40 (4) ◽  
pp. 426-435 ◽  
Author(s):  
Nicholas J. Bax
Keyword(s):  
Chum Salmon ◽  
Pink Salmon ◽  
Puget Sound ◽  
Oncorhynchus Keta ◽  
Daily Mortality ◽  
Chum Salmon Oncorhynchus Keta ◽  
Hood Canal ◽  
Time Period ◽  
Order Of Magnitude ◽  
Juvenile Chum Salmon

The average daily loss in numbers from a group of fluorescently marked, hatchery-reared, juvenile chum salmon (Oncorhynchus keta) remaining in the nearshore zone following their release from the hatchery into southern Hood Canal, Washington State, was estimated at 38–49%. This estimated loss was then adjusted by the estimated maximum emigration of marked fish from the sampling area and the average daily mortality over a 2- and a 4-d time period estimated at between 31 and 46%. These estimates are an order of magnitude higher than estimates of the average daily mortality of naturally emigrating juvenile pink salmon (O. gorbuscha) from the Bella Coola River, British Columbia, over a 40-d time period (Parker 1968). The two studies are contrasted and it is suggested that daily mortality is highly variable over the 40 d subsequent to saltwater entry, with mortality higher initially, particularly for those fish remaining close to their point of saltwater entry.

Competition between juvenile pink (Oncorhynchus gorbuscha) and chum salmon (Oncorhynchus keta) and its effect on growth and survival

1993 ◽  
Vol 71 (6) ◽  
pp. 1270-1274 ◽  
Author(s):  
Terry D. Beacham
Keyword(s):  
Relative Abundance ◽  
Chum Salmon ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Oncorhynchus Keta ◽  
Fraser River ◽  
Growth And Survival ◽  
Competitive Effects ◽  
Chum Salmon Oncorhynchus Keta ◽  
The Mean

Pink (Oncorhynchus gorbuscha) and chum salmon (Oncorhynchus keta) fry have the potential for significant interactions in estuarine and nearshore waters of the Fraser River. Potential competitive effects were investigated by rearing both species for 60 d from fry emergence in monoculture and five duoculture environments (0, 10, 25, 50, 75, 90, and 100% pink salmon, and 100, 90, 75, 50, 25, 10, and 0% chum salmon, respectively), with the total number of fish in each environment constant. As the relative abundance of chum salmon increased, the mean weight of both pink and chum salmon declined, and reduced phenotypic variation in weight was observed. No marked trends in survival were observed in either species, but there was some indication that pink salmon survival was higher at intermediate relative densities of pink and chum salmon. Pink salmon biomass increased from 0.8 to 1.8%/d depending on the environment, and chum salmon biomass increased from 3.2 to 3.8%/d.

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