Download or read book Variable Effects of Biological and Environmental Processes on Coho Salmon Marine Survival in Southeast Alaska written by Michael J. Malick and published by . This book was released on 2008 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: "I examined the relationships between coho salmon Oncorhynchus kisutch marine survival and seven biological and physical covariates across 14 Southeast Alaska (SEAK) stocks. A primary focus of the study was to investigate the influence of pink O. gorbuscha and chum O. keta salmon fry abundances on marine survival. The coho salmon stocks exhibited strong covariation, suggesting common regional processes are influencing marine survival in SEAK. However, only two of the covariates, the North Pacific index and SEAK pink salmon harvest, had consistent relationships across all 14 stocks with both of the covariates relating positively with marine survival. The other covariates all had inconsistent relationships with marine survival. An index representing hatchery pink and chum salmon fry abundance had a stronger estimated effect on marine survival than an index of wild pink salmon fry abundance and SEAK pink salmon harvest numbers. The magnitude and sign of the hatchery pink and chum salmon effect varied greatly among different localities. This study provides evidence that coho salmon stocks throughout SEAK experience some degree of regional concordance in the marine environment, but also that local stock specific conditions are important in fully understanding variation in marine survival"--Leaf iii.

Download or read book Biophysical Factors Associated with the Marine Growth and Survival of Auke Creek Alaska Coho Salmon Oncorhynchus Kisutch written by Joshua Benjamin Robins and published by . This book was released on 2006 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Correlation and stepwise regression analyses were used to investigate relationships between growth in four distinct marine habitats, marine survival, and biophysical indices for Auke Creek coho salmon, a coho salmon population in Southeast Alaska. Early marine growth of males and females were positively correlated, but neither was correlated with early marine growth of jacks. Regional biophysical indices had significant effects on early marine growth of jack, but not on early marine growth of adult coho salmon. Sea surface temperature and number of hatchery pink and churn salmon juveniles released had negative and positive effects on growth in strait habitat, respectively. Hatchery pink and churn salmon abundance and pink salmon catch in Northern Southeast Alaska were negatively related to the growth of Auke Creek coho salmon in the late ocean phase. The average length-at-return of males, but not females, was negatively related to the abundance of hatchery pink and chum salmon. Female and male size-at-return were positively correlated (r = 0.68) but within-year variation was less for females, indicating possible sex-specific differences in adult size requirements associated with reproductive success. Adult survival and jack return rate were significantly related to early marine growth of adults and jacks, respectively, indicating size-selective mortality. Hatchery pink and churn salmon abundance had positive effects on adult survival and jack return rate"--Leaf iii.

Download or read book Marine Survival of Coho Salmon Oncorhynchus Kisutch in Washington State written by Jessica L. Beetz and published by . This book was released on 2009 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Factors Affecting Marine Growth and Survival of Auke Creek Alaska Coho Salmon Oncorhynchus Kisutch written by Ryan Jordan Briscoe and published by . This book was released on 2004 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Correlation analyses and stepwise regression models were run to examine relationships between Auke Creek coho salmon marine survival, scale growth, and a number of physical and biological covariates: local sea surface and air temperatures, local precipitation, the Pacific Decadal Oscillation, local hatchery release numbers, size at return, and regional and state salmon catch numbers. Jack survival and adult survival covaried strongly, suggesting the primary cause of mortality is encountered in the first four or five months of marine life. The number of hatchery fish had the strongest correlation with marine survival (r = 0.71), which could indicate that hatchery releases are prey for Auke Creek coho smolts or buffering these smolts from predators. Sea surface temperature was not significantly associated with adult survival, but was with jack survival. Surprisingly, scale growth was not correlated with marine survival. Adult size appears to be determined in the last year of marine life when the fish are in the Gulf of Alaska. Regional survival trends followed closely with Auke Creek marine survival, indicating factors affecting survival are regional in scope. Specific mechanisms were not defined, but the results indicate biological covariates were more associated with Auke Creek coho survival than were physical covariates"--Leaf iii.

Download or read book Coho Salmon Stock Status and Escapement Goals in Southeast Alaska written by Leon D. Shaul and published by . This book was released on 2011 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reports on the status of coho salmon stocks in Southeast Alaska, which was assessed from information on escapement, smolt abundance, marine survival, and total abundance from coded-wire-tagged indicator stocks and from stocks returning to streams that were surveyed for escapement.

Download or read book Behavior and Survival of Coho Salmon Oncorhynchus Kisutch Walbaum in Sashin Creek Southeastern Alaska written by Richard Allan Crone and published by . This book was released on 1968 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Behavior and survival in fresh water were studied for three brood years of coho salmon in Sashin Creek, Alaska, from October 1963, until September 1966. Investigations of spawning adults were conducted to determine numbers of spawners, distribution on the spawning grounds, effects on pink salmon, age composition, redd life, fecundities, and egg retention. Juvenile coho were studied to determine changes in population size, distribution in the stream, age composition of the population, food habits, and rates of mortality during fresh-water life. The number of coho spawners counted into Sashin Creek each year normally varied from 50 to 300. Weir counts and estimations of the number of spawners determined from observed spawning effort and redd life were not accurate methods of estimating the coho escapement into Sashin Creek. In 1965, a more accurate estimate was obtained by tagging a portion of the run and recording marked to unmarked ratios on the spawning grounds. I estimated that less than two percent of the viable pink salmon embryos were destroyed in 1965 by the spawning activities of coho salmon. Most coho spawners returned to Sashin Creek in 1965 and 1966 in their fourth year of life after having migrated to sea in their third year (designated 43). Smaller numbers of 32 and 54 individuals composed the remainder of the spawning population. The mean redd life of 56 females was 13 days. A small sample of coho from Sashin Creek examined for fecundity in 1966 gave a mean of 2,868 eggs per female. A weir or fyke net was fished in the spring to estimate emigration of juvenile coho. Coho smolts left Sashin Creek from April through July; peak emigration occurred in late May or early June. Coho fry left the stream in the spring and summer in widely varying numbers from year to year. I estimated from growth data, population estimates, and analysis of scale samples that most coho juveniles remained in Sashin Creek for two growing seasons before migrating to sea. Analysis of scales from juvenile coho indicated that some reabsorption of scales occurs during the winter. The possibility of reabsorption of circuli makes back-calculation of the length of younger age-groups of coho from scale measurements unreliable. Diptera were represented more often than any other order of insects in the stomachs of juvenile coho. Hemiptera were important as food items to juvenile coho in a tributary stream. The estimated survival from egg deposition to immediately prior to emergence varied between 17.5 and. 34.9 percent for the three brood years, and averaged 27. 8 percent. Early summer populations of fry were variable in size and dependent on the size of the egg deposition of the brood. Populations of fry declined rapidly during July and early August. Instantaneous mortality rates were much higher for this period than during any other time in the fresh-water life of coho salmon in Sashin Creek. Mortality dropped to a low level during the following winter period.

Download or read book Environmental Biological and Genetic Factors Influencing Local Adaptation of Pink Salmon Oncorhynchus Gorbuscha in Auke Creek Alaska written by Christopher V. Manhard and published by . This book was released on 2016 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pacific salmon form distinct, locally adapted populations because of the spatial and temporal precision with which they home to their natal streams. Local adaptation is recognized as an important component underlying the productivity and sustainability of salmonid populations, yet there remains uncertainty of the scale at which it occurs. This uncertainty was addressed by analysis of demographic, genetic, and experimental data collected from seasonally structured brood lines of Pink Salmon that spawn in Auke Creek, Alaska. An extensive background of research on this system has indicated that the timing of the adult and juvenile migrations is closely aligned with fitness and productivity in this stream; this background provided a framework for synthesizing the results of the analyses to address these questions: (1) What ecological factors influence productivity of the freshwater and marine life history stages; (2) Do these factors suggest a mechanism for evolution of migration time; (3) What are the consequences of disrupting fine-scale local adaptation of migration time? Freshwater productivity appeared to be influenced primarily by competition for spawning habitat, rather than variability in environmental conditions. Marine productivity, conversely, was associated with physical processes that influence survival of juveniles in the nearshore environment. Consistent with these findings, genetic evolution of earlier migration time, which was observed in both adults and juveniles over two generations, appeared to be driven by earlier vernal warming of the nearshore environment. Despite these environmental changes and resulting selection against late migrating fish, recruitment to Auke Creek has remained stable, thereby indicating that seasonal structure of migration time has supported sustained productivity in a changing climate. Experimental relaxation of natural barriers to gene flow that maintain the seasonal structure resulted in intermediate adult migration times in two generations of hybrid fish. These patterns were consistent with an additive genetic basis for migration time and suggest that ecological outbreeding depression is a post-zygotic mechanism that maintains adaptive variation of migration time in Auke Creek. Collectively, these results provide evidence that fine-scale local adaptation can enhance productivity of salmonid populations while providing resilience to climate change.

Download or read book Gale Environmental Sourcebook written by and published by . This book was released on 1994 with total page 968 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pacific Salmon Life Histories written by Cornelis Groot and published by UBC Press. This book was released on 1991 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pacific salmon are an important biological and economic resource of countries of the North Pacific rim. They are also a unique group of fish possessing unusually complex life histories. There are seven species of Pacific salmon, five occurring on both the North American and Asian continents (sockeye, pink, chum, chinook, and coho) and two (masu and amago) only in Asia. The life cycle of the Pacific salmon begins in the autumn when the adult female deposits eggs that are fertilized in gravel beds in rivers or lakes. The young emerge from the gravel the following spring and will either migrate immediately to salt water or spend one or more years in a river or lake before migrating. Migrations in the ocean are extensive during the feeding and growing phase, covering thousands of kilometres. After one or more years the maturing adults find their way back to their home river, returning to their ancestral breeding grounds to spawn. They die after spawning and the eggs in the gravel signify a new cycle. Upon this theme Pacific salmon have developed many variations, both between as well as within species. Pacific Salmon Life Histories provides detailed descriptions of the different life phases through which each of the seven species passes. Each chapter is written by a scientist who has spent years studying and observing a particular species of salmon. Some of the topics covered are geographic distribution, transplants, freshwater life, ocean life, development, growth, feeding, diet, migration, and spawning behaviour. The text is richly supplemented by numerous maps, illustrations, colour plates, and tables and there is a detailed general index, as well as a useful geographical index.

Download or read book The Behavior and Ecology of Pacific Salmon and Trout written by Thomas P. Quinn and published by UBC Press. This book was released on 2011-11-01 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Behavior and Ecology of Pacific Salmon and Trout explains the patterns of mate choice, the competition for nest sites, and the fate of the salmon after their death. It describes the lives of offspring during the months they spend incubating in gravel, growing in fresh water, and migrating out to sea to mature. This thorough, up-to-date survey should be on the shelf of everyone with a professional or personal interest in Pacific salmon and trout. Written in a technically accurate but engaging style, it will appeal to a wide range of readers, including students, anglers, biologists, conservationists, legislators, and armchair naturalists.

Download or read book Stock Enhancement and Sea Ranching written by Kenneth M. Leber and published by John Wiley & Sons. This book was released on 2008-04-15 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: The collapse of many of the World’s fisheries continues to be of major concern and the enhancement of fish stocks through techniques such as ranching is of huge importance and interest across the globe. This important book, which contains fully peer reviewed and carefully edited papers from the 2nd International Symposium in Stock Enhancement and Sea Ranching is broadly divided into sections covering the following areas: The present situation of stock enhancement Seed quality and techniques for effective stocking Health management of hatchery stocks Methods for evaluating stocking effectiveness Population management in stock enhancement and sea ranching Management of stocked populations Ecological interactions with wild stocks Genetic management of hatchery and wild stocks Socio-economics of stock enhancement Case studies Stock Enhancement and Sea Ranching has been written and edited by some of the world’s foremost authorities in fisheries science and related areas and is essential reading for all fisheries scientists throughout the World. Fish biologists, marine and aquatic scientists, environmental biologists, ecologists, conservationists, aquaculture personnel and oceanographers will all find much of use and interest within this book. All libraries within universities and research establishments where these subjects are studied and taught should have copies of this book on their shelves.

Download or read book Wildlife Disease Ecology written by Kenneth Wilson and published by Cambridge University Press. This book was released on 2019-11-14 with total page 693 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduces readers to key case studies that illustrate how theory and data can be integrated to understand wildlife disease ecology.

Download or read book Preseason Report written by and published by . This book was released on 2002 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Physiological Ecology of Pacific Salmon written by Cornelis Groot and published by UBC Press. This book was released on 2010-10-01 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: Every year, countless juvenile Pacific salmon leave streams and rivers on their migration to feeding grounds in the North Pacific Ocean and the Bering Sea. After periods ranging from a few months to several years, adult salmon enter rivers along the coasts of Asia and North America to spawn and complete their life cycle. Within this general outline, various life history patterns, both among and within species, involve diverse ways of exploiting freshwater, estuarine, and marine habitats. There are seven species of Pacific salmon. Five (coho, chinook chum, pink, and sockeye) occur in both North America and Asia. Their complex life histories and spectacular migrations have long fascinated biologists and amateurs alike. Physiological Ecology of Pacific Salmon provides comprehensive reviews by leading researchers of the physiological adaptations that allow Pacific Salmon to sustain themselves in the diverse environments in which they live. It begins with an analysis of energy expenditure and continues with reviews of locomotion, growth, feeding, and nutrition. Subsequent chapters deal with osmotic adjustments enabling the passage between fresh and salt water, nitrogen excretion and regulation of acid-base balance, circulation and gas transfer, and finally, responses to stress. This thorough and authoritative volume will be a valuable reference for students and researchers of biology and fisheries science as they seek to understand the environmental requirements for the perpetuation of these unique and valuable species.

Download or read book Synopsis of Biological Data on the Chum Salmon Oncorhynchus Keta Walbaum 1792 written by Richard G. Bakkala and published by . This book was released on 1970 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Information Report written by and published by . This book was released on 1985 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Atlantic Salmon Ecology written by Øystein Aas and published by John Wiley & Sons. This book was released on 2011-07-05 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Atlantic salmon is one of the most prized and exploited species worldwide, being at the centre of a massive sports fishing industry and increasingly as the major farmed species in many countries worldwide. Atlantic Salmon Ecology is a landmark publication, both scientifically important and visually attractive. Comprehensively covering all major aspects of the relationship of the Atlantic salmon with its environment, chapters include details of migration and dispersal, reproduction, habitat requirements, feeding, growth rates, competition, predation, parasitsm, population dynamics, effects of landscape use, hydro power development, climate change, and exploitation. The book closes with a summary and look at possible future research directions. Backed by the Norwegian Research Council and with editors and contributors widely known and respected, Atlantic Salmon Ecology is an essential purchase for all those working with this species, including fisheries scientists and managers, fish biologists, ecologists, physiologists, environmental biologists and aquatic scientists, fish and wildlife department personnel and regulatory bodies. Libraries in all universities and research establishments where these subjects are studied and taught should have copies of this important publication. Comprehensive and up-to-date coverage of Atlantic Salmon Atlantic Salmon is one of the world's most commercially important species Backed by the Norwegian Research Council Experienced editor and internationally respected contributors