Download or read book Adaptive Diversification of Juvenile Life Histories in the Chinook Salmon Oncorhynchus Tshawytscha Walbaum written by Eric Burke Taylor and published by . This book was released on 1989 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Juvenile Life Histories of Rogue River Spring Chinook Salmon Oncorhynchus Tshawytscha Walbaum as Determined by Scale Analysis written by Mark D. Schluchter and published by . This book was released on 1977 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sport Fishery Abstracts written by and published by . This book was released on 1990 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canadian Journal of Fisheries and Aquatic Sciences written by and published by . This book was released on 1990 with total page 990 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fisheries Review written by and published by . This book was released on 1990 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Juvenile Chinook Salmon Oncorhynchus Tshawytscha Life History Diversity and Growth Variability in a Large Freshwater Tidal Estuary written by Pascale A. L. Goertler and published by . This book was released on 2014 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: For many fish and wildlife species, a mosaic of available habitats is required to complete their life cycle, and is considered necessary to ensure population stability and persistence. Particularly for young animals, nursery habitats provide opportunities for rapid growth and high survival during this vulnerable life stage. My thesis focuses on juvenile Chinook salmon (Oncorhynchus tshawytscha) and their use of estuarine wetlands as nursery habitat. Estuaries are highly productive systems representing a mosaic of habitats connecting rivers to the sea, and freshwater tidal estuaries provide abundant prey communities, shade, refuge from predation and transitional habitat for the osmoregulatory changes experienced by anadromous fishes. I will be discussing the freshwater tidal wetland habitat use of juvenile Chinook salmon in the Columbia River estuary, which are listed under the Endangered Species Act. I used otolith microstructural growth estimates and prey consumption to measure rearing habitat quality. This sampling effort was designed to target as much genetic diversity as possible, and individual assignment to regional stocks of origin was used to describe the diversity of juvenile Chinook salmon groups inhabiting the estuary. Diversity is important for resilience, and in salmon biocomplexity within fish stocks has been shown to ensure collective productivity despite environmental change. However much of the research which links diversity to resilience in salmon has focused on the adult portion of the life cycle and many resource management policies oversimplify juvenile life history diversity. When this oversimplification of juvenile life history diversity is applied to salmon conservation it may be ignoring critical indicators for stability. Therefore in addition to genetic diversity I also explore methods for better defining juvenile life history diversity and its application in salmon management, such as permitting requirements, habitat restoration, hydropower practices and hatchery management. This study addresses how juvenile salmon growth changes among a range of wetland habitats in the freshwater tidal portion of the Columbia River estuary and how growth variation describes and contributes to life history diversity. To do this, I incorporated otolith microstructure, individual assignment to regional stock of origin, GIS habitat mapping and diet composition, in three habitats (mainstem river, tributary confluence and backwater channel) along ~130 km of the upper estuary. For my first chapter I employed a generalized linear model (GLM) to test three hypotheses: juvenile Chinook growth was best explained by (1) temporal factors, (2) habitat use, or (3) demographic characteristics, such as stock of origin or the timing of seaward migration. I found that variation in growth was best explained by habitat type and an interaction between fork length and month of capture. Juvenile Chinook salmon grew faster in backwater channel habitat and later in the summer. I also found that mid-summer and late summer/fall subyearlings had the highest estuarine growth rates. When compared to other studies in the basin these juvenile Chinook grew on average 0.23, 0.11-0.43 mm/d in the freshwater tidal estuary, similar to estimates in the brackish estuary, but ~4 times slower than those in the plume and upstream reservoirs. However, survival studies from the system elucidated a possible tradeoff between growth and survival in the Columbia River basin. These findings present a unique example of the complexity in understanding the influences of the many processes that generate variation in growth rate for juvenile anadromous fish inhabiting estuaries. In my second chapter, I used otolith microstructure and growth trends produced in a dynamic factor analysis (DFA, a multivariate time series method only recently being used in fisheries) to identify the life history variation in juvenile Chinook salmon caught in the Columbia River estuary over a two-year period (2010-2012). I used genetic assignment to stock of origin and capture location and date with growth trajectories, as a proxy for habitat transitions, to reconstruct life history types. DFA estimated four to five growth trends were present in juvenile Chinook salmon caught in the Columbia River estuary, diversity currently being simplified in many management practices. Regional stocks and habitats did not display divergent growth histories, but the marked hatchery fish did ordinate very similarly in the trend loadings from the DFA analysis, suggesting that hatchery fish may not experience the same breadth of growth variability as wild fish. I was not able to quantify juvenile life history diversity, and juvenile Chinook life history diversity remains difficult to catalog and integrate into species conservation and habitat restoration for resource management. However, by expanding our understanding of how juvenile Chinook salmon experience their freshwater rearing environment we improve our capacity to conserve and manage salmon populations. The findings from my thesis provide the necessary information for a restoration framework to link habitat features with salmon management goals, such as juvenile growth, wild and genetic origin and life history diversity.
Download or read book Microevolution Rate Pattern Process written by Andrew P. Hendry and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: From guppies to Galapagos finches and from adaptive landscapes to haldanes, this compilation of contributed works provides reviews, perspectives, theoretical models, statistical developments, and empirical demonstrations exploring the tempo and mode of microevolution on contemporary to geological time scales. New developments, and reviews, of classic and novel empirical systems demonstrate the strength and diversity of evolutionary processes producing biodiversity within species. Perspectives and theoretical insights expand these empirical observations to explore patterns and mechanisms of microevolution, methods for its quantification, and implications for the evolution of biodiversity on other scales. This diverse assemblage of manuscripts is aimed at professionals, graduate students, and advanced undergraduates who desire a timely synthesis of current knowledge, an illustration of exciting new directions, and a springboard for future investigations in the study of microevolution in the wild.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1990 with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Return to the River written by Richard N. Williams and published by Elsevier. This book was released on 2005-11-21 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt: Return to the River will describe a new ecosystem-based approach to the restoration of salmon and steelhead populations in the Columbia River, once one of the most productive river basins for anadromous salmonids on the west coast of North America. The approach of this work has broad applicability to all recovery efforts throughout the northern hemisphere and general applicability to fisheries and aquatic restoration efforts throughout the world. The Pacific Northwest is now embroiled in a major public policy debate over the management and restoration of Pacific salmon. The outcome of the debate has the potential to affect major segments of the region's economy - river transportation, hydroelectric production, irrigated agriculture, urban growth, commercial and sport fisheries, etc. This debate, centered as it is on the salmon in all the rivers, has created a huge demand for information. The book will be a powerful addition to that debate. - A 15 year collaboration by a diverse group of scientists working on the management and recovery of salmon, steelhead trout, and wildlife populations in the Pacific Northwest - Includes over 200 figures, with four-color throughout the book - Discusses complex issues such as habitat degradation, juvenile survival through the hydrosystem, the role of artificial production, and harvest reform
Download or read book Life History of Fall run Juvenile Chinook Salmon Oncorhynchus Tshawytscha in the Sacaramento San Joaquin Estuary California written by Martin A. Kjelson and published by . This book was released on 1982 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Variations in Estuarine Life History Diversity of Juvenile Chinook Salmon Based on Stable Isotope Analysis of Food Web Linkages written by Greer O. Anderson and published by . This book was released on 2006 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Life Histories of Juvenile Chinook Salmon Oncorhynchus Tshawytscha in the Columbia River Estuary as Inferred from Scale and Otolith Microchemistry written by Lance A. Campbell and published by . This book was released on 2010 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite evidence that juvenile Chinook salmon (Oncorhynchus tshawytscha) utilize North Pacific estuaries for growth and salinity acclimation, research in the Columbia River estuary has lead to opposing hypotheses about the estuary's importance as a salmon rearing environment. Many contemporary tagging studies indicate that salmon residency within the estuary is short (
Download or read book Connecting Tidal fluvial Life Histories to Survival of McKenzie River Spring Chinook Salmon Oncorhynchus Tshawytscha written by Gordon W. Rose and published by . This book was released on 2015 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chinook salmon returns to the Columbia River basin have declined due to impacts of a growing human population, despite significant mitigation expenditures. Consequently, fisheries managers have become focused on recovery and long-term viability of at-risk populations. A viable population depends, in part, on the connectivity and quality of diverse habitat types salmon require to complete their anadromous life-cycles. The tidal-fluvial Columbia River estuary is one link in this chain of habitats, but was largely over-looked as important Chinook salmon habitat until recently. Habitat restoration projects are underway in the tidal Columbia River estuary with the goal of increasing survival benefits to juvenile Chinook salmon. However, knowledge gaps remain about stock-specific use of tidal-fluvial habitat and tracking these restoration efforts is largely subjective. This study has sought to quantify the importance of tidal-fluvial habitat for a critical population of Chinook salmon, from the McKenzie River in the upper Willamette River Basin. Using otolith micro-chemistry profile analysis, juvenile net growth in the tidal-fluvial Columbia River was back-calculated for 92 natural-origin McKenzie River Chinook salmon across outmigration years 2005 and 2006. All otoliths were sampled from McKenzie River adult salmon to draw inferences about the juvenile life histories of surviving spawners. Mean ± SD net growth in the tidal fluvial estuary for all years was 5.48 ± 5.81 mm for subyearlings and 7.43 ± 8.32mm for yearlings. Differences in mean net growth by juvenile life-history type were not significant despite a prevailing assumption that subyearlings rear longer in estuary habitat than yearlings. Emigration sizes and net-growth estimates were significantly greater for subyearlings in outmigration year 2005 than 2006; there was only suggestive evidence emigration sizes were greater for yearlings in outmigration year 2005 than 2006, and net-growth estimates were similar between years. Sixteen percent (15 of 92) of McKenzie Chinook salmon grew between 10 and 43 mm over approximately 25-100 days in the tidal-fluvial Columbia River. Extended rearing in tidal-fluvial habitat provided an alternate life-history pathway for some yearling (12), fingerling (one), and fry (two) migrants. Subyearlings with intermediate-rearing or migratory life history pathways had greater net growth in tidal-fluvial habitat during 2005 than 2006, and in 2005 environmental conditions were unfavorable to overall salmon productivity. Fixed effects linear regression models suggest tidal-fluvial habitat supports McKenzie Chinook salmon life-history diversity, growth, and size, and therefore likely contributes to population resilience.
Download or read book Change in Pacific Northwest Coastal Ecosystems written by Gregory R. McMurray and published by . This book was released on 1998 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Range wide Life history Diversity and Climate Exposure in Chinook Salmon written by Anna Potapova and published by . This book was released on 2022 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate change risk for migratory species is intertwined with their life-history diversity. Here I quantify climate risk, exposure, and phenological adaptive capacity in Chinook salmon during their spawning migrations for populations from across their North American range. First, I assessed how migration timing varies with watershed characteristics. Populations with longer migration distances and from higher elevations entered freshwater earlier. Second, I quantified climate exposure and risk by linking migration timing data to recent (1990s) and future (2040s) water temperatures. Nearly a quarter of populations will be exposed to future temperatures above thermally stressful thresholds. Third, I assessed the rate and direction of phenological shifts that would enable Chinook to adapt to climate warming. Spring populations would need to shift earlier, while fall populations would need to shift later. Broadly, my thesis highlights that climate exposure, risk and adaptive capacity are structured by phenology and latitude in a diverse migratory species.
Download or read book The Freshwater Fishes of British Columbia written by J. D. McPhail and published by University of Alberta. This book was released on 2007-09-28 with total page 697 pages. Available in PDF, EPUB and Kindle. Book excerpt: The threat of deteriorating habitats and a loss of biodiversity make this reference work on the freshwater fishes of British Columbia more necessary than ever before. Eighty-one comprehensive species accounts aid accurate identification and consist of an illustration, the scientific and common names of the fish, its distinguishing characteristics, taxonomic comments, geographic distribution, a life-history summary, a habitat-use summary, and conservation comments. The book is a critical resource for biologists, naturalists, management and conservation officers, anglers, and members of the public who are concerned about our natural heritage. Foreword by Joseph S. Nelson.
