![Formation of Otolith Growth Increments and Their Potential for Assessing the Early Life History of Chinook Salmon (Oncorhynchus Tshawytscha) [microform] PDF](https://books.google.com/books/content/images/frontcover/izzCwgEACAAJ?fife=w150-h200)
Author: John D. NeilsonPublisher: National Library of Canada
ISBN: 9780315180291
Category : Chinook salmon
Languages : en
Pages : 306
Book Description
Formation of Otolith Growth Increments and Their Potential for Assessing the Early Life History of Chinook Salmon (Oncorhynchus Tshawytscha) [microform]
![Formation of Otolith Growth Increments and Their Potential for Assessing the Early Life History of Chinook Salmon (Oncorhynchus Tshawytscha) [microform] PDF](https://books.google.com/books/content/images/frontcover/izzCwgEACAAJ?fife=w80-h100)
Author: John D. NeilsonPublisher: National Library of Canada
ISBN: 9780315180291
Category : Chinook salmon
Languages : en
Pages : 306
Book Description
Canadiana
Author: Growth-increment Formation Using Otoliths and Scales of Juvenile Chinook Salmon
Author: Brian Michael WalkerPublisher:
ISBN:
Category : Chinook salmon
Languages : en
Pages : 104
Book Description
Freshwater growth of juvenile Chinook salmon Oncorhynchus tshawytscha influences survival and recruitment to the adult population. Retrospective analysis is used to measure salmon growth at previous ages, with fish size and growth assumed to be accurately reflected by otolith increments and scale circuli. I conducted a 122-d laboratory experiment to validate the relationship among body size, growth, and width to daily otolith growth increments and scale circuli in juvenile stream-type Chinook salmon. Fish total length was found to be proportional to otolith axis length (r2 = 0.209, p
The Use of Otolith Daily Increment Widths to Estimate the Size and Growth of Juvenile Chinook Salmon (Oncorhynchus Tshawytscha) [microform]
![The Use of Otolith Daily Increment Widths to Estimate the Size and Growth of Juvenile Chinook Salmon (Oncorhynchus Tshawytscha) [microform] PDF](https://books.google.com/books/content/images/frontcover/xsnIwgEACAAJ?fife=w80-h100)
Author: Bradford, Michael JPublisher: National Library of Canada
ISBN: 9780315308107
Category : Chinook salmon
Languages : en
Pages : 168
Book Description
Otolith Microstructure Examination and Analysis
Author: David K. StevensonPublisher: McClain Printing Company
ISBN:
Category : Medical
Languages : en
Pages : 422
Book Description
The field of otolith microstructure research has experienced phenomenal growth since the early 1970s and now forms the basis for hundreds of studies in early life history, age, growth, recruitment, migration, mortality and stock structure. This book represents the first effort to compile and summarize the many techniques and procedures associated with studies of otolith microstructure. The complete sequence of events, from sample collection to data analysis, is covered comprehensively, so as to be applicable to most species and situations. The various chapters include both published and unpublished procedures.
Natural Reproduction and Recruitment of Chinook Salmon in the Salmon River, New York: An Application of Otolith Microstructure Analysis
Author: Nathan Gail SmithPublisher:
ISBN: 9780542350764
Category :
Languages : en
Pages : 72
Book Description
Stocking of hatchery-reared Chinook salmon (Oncorhynchus tshawytscha) in Lake Ontario has led to the development of a sport fishery that provides high economic returns to local communities. Changes in habitat quality, including changes in flow associated with Federal Energy Regulatory Commission reauthorization protocols since the mid 1990s in the Salmon River, NY, may have led to increased natural reproduction in this river. Increases in natural production of Chinook in Lake Ontario could lead to changing management practices in the fishery. In order to measure wild reproduction I used known origin young-of-the-year (YOY) Chinook salmon from hatchery and wild sources as a baseline for separating these groups using otolith microstructure. Measuring 20 days growth from 300 mum inward toward the origin correctly classified 100% of known hatchery fish, and 89% of known wild fish. These measurements were used to determine the origin of Chinook salmon smolts caught in the nearshore of Lake Ontario adjacent to the Salmon River, NY in 2000 (85%) and 2001 (89%). I also evaluated the potential for carbon and oxygen stable isotopes in otoliths for differentiation of hatchery and wild YOY Chinook. Stable isotope methods show promise in separating hatchery and wild fish based on known-origin otoliths from 1999 and 2001, but further research is required before large scale application in Lake Ontario. In addition to sampling outmigrating smolts, I applied the 300 mum method to a sample of adults returning to the Salmon River from 2000-2002. Wild origin fish contributed between 10 and 25% of the returning adults for the 6 year classes 1995-2000. There was no time trend in the proportion of wild fish and therefore no evidence for an increase in natural production due to water flow changes in the Salmon River during the late 1990s. Because of the life history of Chinook salmon and time limitations of the study, I was unable to directly compare estimates of smolts from 2000-2001 with returning adults from those year classes, however my results for both YOY and adult Chinook indicate that natural reproduction may play a larger role in Lake Ontario than previously thought.
Natural Reproduction and Recruitment of Chinook Salmon in the Salmon River, NY
Author: Nathan Gail SmithA Comparison of the Growth Histories of Pre- and Post-decline Brood Years of Sockeye Salmon (Oncorhynchus Nerka) from Rivers Inlet Based on Otolith Analysis and in Relation to Environmental Conditions
Author: Claire Anne Li LoongPublisher:
ISBN:
Category : Otoliths
Languages : en
Pages : 196
Book Description
The widths of growth zones recorded on otoliths of sockeye salmon (Oncorhynchus nerka) from Rivers Inlet were measured to assess the impacts of environmental conditions on growth at different life history stages. Otoliths from the pre-decline (1984-1987) and post-decline brood years (1997-2005) were compared. Post-decline juveniles were significantly larger than pre-decline individuals during the migration to sea, but grew less in the first marine year. Final size was not significantly different between time periods. Functional regression analyses were performed to investigate the relationship between otolith growth and sea surface salinity at McInnes Island. Otolith growth was positively correlated with salinity during September and October. Decreased salinity under a 30 ppt threshold appears to have signalled recent unfavourable oceanic conditions for growth and possibly survival.
The Effect of Parental Age-class on the Early Life History of Hatchery-reared Chinook Salmon, Oncorhynchus Tshawytscha
Author: Charles Wilfred HopleyPublisher:
ISBN:
Category : Chinook salmon
Languages : en
Pages : 106
Book Description
Factors Affecting Overwinter Mortality and Early Marine Growth in the First Ocean Year of Juvenile Chinook Salmon in Quatsino Sound, British Columbia
Author: Katherine Rose MiddletonPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Evidence suggests that the variability in recruitment of adult Pacific salmon is related to smolt survival during the first ocean year. Specifically, the first few weeks and first marine winter may be two critical periods of high mortality during early marine life. Mortality during early marine residency has been attributed to predation and size-dependent factors while high mortality during the first winter may be due to energy deficits and failure to reach a certain size by the end of the growing season. My study assessed factors influencing overwinter mortality and early marine growth in juvenile Chinook salmon (Oncorhynchus tshawytscha) from Marble River, Quatsino Sound, British Columbia. Juvenile salmon were collected during November 2005 and 2006 (fall) and March 2006 and 2007(winter). Mortality rates over the first winter derived from catch per unit effort across seasons ranged between 80-90% in all years. These are the first estimations of overwinter mortality in juvenile Pacific salmon. Fish size distributions showed no evidence of size-selective overwinter mortality between fall and winter fish in either 2005-2006 or 2006-2007. Otolith microstructure analyses showed no significant difference in circulus increment widths during the first four weeks after marine entry. Similarities in increment width indicated that early marine growth did not differ between fall and winter fish during early marine residency in 2006. These observations show that the high overwinter mortality rates of juvenile Chinook salmon in Quatsino Sound are not size-dependent. Total plankton biomass was significantly lower in the winter season but size distribution, gut fullness and energy density data did not show evidence of starvation. No correlation was found between early marine growth, size, energy accumulation and high mortality in Marble River juvenile Chinook salmon during their first ocean winter in Quatsino Sound. Possible factors influencing these high mortality rates may include non size-selective predation, disease, local environmental influences or an as yet unknown source. Future work should continue to focus on understanding the relationship between early marine survival and adult recruitment. The expansion of growth comparisons geographically and chronologically while determining the effects of predatory mortality on juvenile Chinook salmon along the north Pacific continental shelf and beyond are imperative to fully understanding this complex marine life stage.