Evidence That Reduced Early Marine Growth is Associated with Lower Marine Survival of Coho Salmon

Abstract Coho salmon Oncorhynchus kisutch from the Strait of Georgia were used to test the hypothesis that slower growing fish in their first ocean year had lower survival over the late fall and winter than faster growing fish. The Strait of Georgia provided a suitable area for this study because it is a semi-enclosed rearing area for juvenile Pacific salmon that is distinct from the open marine rearing areas off the west coast. Coho salmon that survived the winter had significantly larger spacing between circuli on scales, indicating that brood year strength is related to growth in the first marine year. Other studies have shown that smaller fish of a cohort are less able to survive periods of energy deficit than larger fish. Thus, size-related mortality in the first marine fall and winter may be an important determinant of brood year strength of some coho salmon stocks and stocks of other species of Pacific salmon.

[1]  K. Rose,et al.  Is density-dependent growth in young-of-the-year fishes a question of critical weight? , 2000, Reviews in Fish Biology and Fisheries.

[2]  R. Beamish,et al.  Replacement of Wild Coho Salmon by Hatchery-Reared Coho Salmon in the Strait of Georgia over the past Three Decades , 2003 .

[3]  Oceans Canada,et al.  Forecast for Southern British Columbia Coho Salmon in 2001 , 2001 .

[4]  Richard J. Beamish,et al.  A critical size and period hypothesis to explain natural regulation of salmon abundance and the linkage to climate and climate change , 2001 .

[5]  K. Friedland,et al.  Growth patterns of Labrador Sea Atlantic salmon postsmolts and the temporal scale of recruitment synchrony for North American salmon stocks , 2000 .

[6]  R. Beamish,et al.  Estimating the Abundance of Juvenile Coho Salmon in the Strait of Georgia by Means of Surface Trawls , 2000 .

[7]  Beamish,et al.  Trends in coho marine survival in relation to the regime concept , 2000 .

[8]  Susan M. Sogard,et al.  Endurance of simulated winter conditions by age‐0 walleye pollock: effects of body size, water temperature and energy stores , 2000 .

[9]  R. Foy,et al.  Winter Feeding and Changes in Somatic Energy Content of Age-0 Pacific Herring in Prince William Sound, Alaska , 1999 .

[10]  R. Beamish,et al.  Taking the Next Step in Fisheries Management , 1999 .

[11]  D. Conover,et al.  The allometry of energy reserve depletion: test of a mechanism for size-dependent winter mortality , 1999, Oecologia.

[12]  R. Beamish,et al.  Recent declines in the recreational catch of coho salmon (Oncorhynchus kisutch) in the Strait of Georgia are related to climate , 1999 .

[13]  K. Friedland,et al.  Marine post‐smolt growth and age at maturity of Atlantic salmon , 1996 .

[14]  L. Miranda,et al.  Length‐Dependent Winter Survival and Lipid Composition of Age‐0 Largemouth Bass in Bay Springs Reservoir, Mississippi , 1994 .

[15]  Kevin D. Friedland,et al.  Marine survival of North American and European Atlantic salmon: effects of growth and environment , 1993 .

[16]  R. Beamish,et al.  Pacific salmon production trends in relation to climate , 1993 .

[17]  E. L. Brannon,et al.  Ocean Ecology of North Pacific Salmonids , 1993 .

[18]  J. Post,et al.  Climate, Population Viability, and the Zoogeography of Temperate Fishes , 1990 .

[19]  T. Johnson,et al.  Size‐Dependent Winter Mortality of Young‐of‐the‐Year White Perch: Climate Warming and Invasion of the Laurentian Great Lakes , 1990 .

[20]  J. Fisher Spacing of scale circuli versus growth rate in young coho salmon. , 1990 .

[21]  W. Calder Size, Function, and Life History , 1988 .

[22]  R. Walker,et al.  Circuli spacing and annulus formation: is there more than meets the eye? The case for sockeye salmon, Oncorhynchus nerka , 1988 .

[23]  Statistical interrelation of length, growth, and scale circulus spacing: appraisal of a growth rate estimator for fish , 1987 .

[24]  K. Schmidt-Nielsen,et al.  Scaling, why is animal size so important? , 1984 .

[25]  E. F. Prentice,et al.  The application of recent smoltification research to public hatchery releases: An assessment of size/time requirements for Columbia River hatchery coho salmon (Oncorhynchus kisutch) , 1982 .

[26]  J. Oliver,et al.  Overwinter Mortality of Fingerling Smallmouth Bass in Relation to Size, Relative Energy Stores, and Environmental Temperature , 1979 .

[27]  R. L. Hunt Overwinter Survival of Wild Fingerling Brook Trout in Lawrence Creek, Wisconsin , 1969 .

[28]  R. Parker Marine Mortality Schedules of Pink Salmon of the Bella Coola River, Central British Columbia , 1968 .

[29]  H. Bilton Characteristics of Scales from Pink Salmon (Oncorhynchus gorbuscha) Transplanted from the Glendale River in Central British Columbia to the North Harbour River in Newfoundland , 1966 .