Length-at-age and Size-Selective Mortality of the Western Basin Lake Erie Walleye (Sander Vitreus) Population, 2000--2008

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ISBN 13 : 9780494762790
Total Pages : pages
Book Rating : 4.7/5 (627 download)

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Book Synopsis Length-at-age and Size-Selective Mortality of the Western Basin Lake Erie Walleye (Sander Vitreus) Population, 2000--2008 by : Emily Crisovan

Download or read book Length-at-age and Size-Selective Mortality of the Western Basin Lake Erie Walleye (Sander Vitreus) Population, 2000--2008 written by Emily Crisovan and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Fluctuations in Growth and Year-class Strength of the Walleye in Saginaw Bay

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ISBN 13 :
Total Pages : 60 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Fluctuations in Growth and Year-class Strength of the Walleye in Saginaw Bay by : Ralph Oscar Hile

Download or read book Fluctuations in Growth and Year-class Strength of the Walleye in Saginaw Bay written by Ralph Oscar Hile and published by . This book was released on 1954 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Genetic Differentiation of Walleye Stocks in Lake St. Clair and Western Lake Erie

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ISBN 13 :
Total Pages : 26 pages
Book Rating : 4.3/5 ( download)

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Book Synopsis Genetic Differentiation of Walleye Stocks in Lake St. Clair and Western Lake Erie by : Thomas N. Todd

Download or read book Genetic Differentiation of Walleye Stocks in Lake St. Clair and Western Lake Erie written by Thomas N. Todd and published by . This book was released on 1990 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Estimation of Regional Mortality Rates for Lake Erie Walleye Sander Vitreus Using Spatial Tag-recovery Modeling

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ISBN 13 : 9781303874659
Total Pages : 172 pages
Book Rating : 4.8/5 (746 download)

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Book Synopsis Estimation of Regional Mortality Rates for Lake Erie Walleye Sander Vitreus Using Spatial Tag-recovery Modeling by : Christopher S. Vandergoot

Download or read book Estimation of Regional Mortality Rates for Lake Erie Walleye Sander Vitreus Using Spatial Tag-recovery Modeling written by Christopher S. Vandergoot and published by . This book was released on 2014 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Climate and Dynamics of Walleye (Sander Vitreus, Formerly Stizostedion Vitreum Vitreum) Populations in North America [microform]

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Publisher : Library and Archives Canada = Bibliothèque et Archives Canada
ISBN 13 : 9780494078679
Total Pages : 394 pages
Book Rating : 4.0/5 (786 download)

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Book Synopsis Climate and Dynamics of Walleye (Sander Vitreus, Formerly Stizostedion Vitreum Vitreum) Populations in North America [microform] by : Zhao, Yingming

Download or read book Climate and Dynamics of Walleye (Sander Vitreus, Formerly Stizostedion Vitreum Vitreum) Populations in North America [microform] written by Zhao, Yingming and published by Library and Archives Canada = Bibliothèque et Archives Canada. This book was released on 2005 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climatic conditions significantly influenced growth of walleye in North America. Genetically distinct walleye populations appear to have developed their own adaptation strategies to respond to their regional climatic conditions. Walleye early growth rate showed a significant latitudinal trend: the populations at low latitudes, experiencing high thermal input, had a high early growth rate (o) and a high value for k, the rate of approaching asymptotic length (Linfinity) as defined in the von Bertalanffy growth model. However, the impact of climatic conditions on walleye growth in later life, as characterized by L infinity was not significant. In Lake Erie, three walleye sub-populations (i.e. the western basin, Van Buren Bay, and Grand River) showed distinct demographic characteristics. The western basin walleye had a lower early growth rate than the eastern basin walleye. The differences in early growth rate among these walleye subpopulations were associated with the differences in thermal regimes experienced by each sub-population during the growing season. The overheated western basin provided the worst growth habitat for walleye during summer/fall. Younger fish cannot avoid these overheated conditions and thus may be exhibiting reduced growth rates because of the unsuitable growth habitat in the western basin. The survival rates of adult walleye in the eastern basin were higher than the lakewide average, but the abundance was less than one percent of the lakewide adult walleye abundance. The warmer and clearer water conditions in 1998 created more walleye habitat than in 1993. The increases in water temperature and decreases in water level that may result from climate change will have different impacts on the habitat suitable for walleye among the three basins, with the greatest effect in the western basin. A simulation study showed that density-dependent early survival and density-dependent adult growth and egg production significantly affect the dynamics of the walleye metapopulation in Lake Erie. Walleye early survival (i.e. recruitment) could be a bottleneck, setting the overall sizes of the western basin and eastern basin sub-populations. This bottleneck would be sensitive to the changes in habitat expected from climate change.

Evaluation of the Intraspecific Effects of a 15-inch Minimum Size Limit on Walleye (Sander Vitreus) Populations in Northern Wisconsin

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ISBN 13 :
Total Pages : 232 pages
Book Rating : 4.:/5 (319 download)

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Book Synopsis Evaluation of the Intraspecific Effects of a 15-inch Minimum Size Limit on Walleye (Sander Vitreus) Populations in Northern Wisconsin by : Michelle Lee LeBeau

Download or read book Evaluation of the Intraspecific Effects of a 15-inch Minimum Size Limit on Walleye (Sander Vitreus) Populations in Northern Wisconsin written by Michelle Lee LeBeau and published by . This book was released on 2004 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Growth and Population Evaluation of Walleye (Sander Vitreus Mitchill) Using Scales and Otoliths as the Aging Structure in Norfork Lake and Bull Shoals Lake

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Publisher :
ISBN 13 :
Total Pages : 88 pages
Book Rating : 4.:/5 (526 download)

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Book Synopsis Growth and Population Evaluation of Walleye (Sander Vitreus Mitchill) Using Scales and Otoliths as the Aging Structure in Norfork Lake and Bull Shoals Lake by : Stephen Christopher Canter

Download or read book Growth and Population Evaluation of Walleye (Sander Vitreus Mitchill) Using Scales and Otoliths as the Aging Structure in Norfork Lake and Bull Shoals Lake written by Stephen Christopher Canter and published by . This book was released on 2009 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: Growth estimations and age frequencies of walleyes (Sander vitreus) were compared using scales and otoliths as the aging structures from Bull Shoals Lake, Missouri and Norfork Lake, Arkansas and Missouri. Aging structures were collected from fish sampled by electro-fishing during the spring of 2008. Each age structure was independently examined by three people without prior knowledge of the fish age, length, weight, gender, or site. Age distributions and growth models were obtained based on scale and otolith age data. Comparisons were made between distributions obtained using each aging structure and between lakes. It was found that scales consistently underestimate the age of fish from both lakes, assuming that otolith age data was accurate. The oldest fish age by scales from both lakes was 6 years, while the oldest fish age using otoliths was 11 years. Growth rates were compared to determine differences between aging structures and lake populations. Power growth models were created to compare growth between Lake Norfork and Bull Shoals Lake. It was found there were significantly different slopes and intercepts, for power growth models using scales and otoliths. Von Bertalanffy growth curves were created to compare growth rates between Lake Norfork and Bull Shoals Lake. Using otoliths as the aging structure it was found that growth rates in Bull Shoals Lake were slightly higher than Lake Norfork.

Estimates of Some Vital Statistics of Northern Pike, Walleye, and Sauger Populations in Lake Sharpe, South Dakota

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ISBN 13 :
Total Pages : 20 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Estimates of Some Vital Statistics of Northern Pike, Walleye, and Sauger Populations in Lake Sharpe, South Dakota by : Joseph H. Elrod

Download or read book Estimates of Some Vital Statistics of Northern Pike, Walleye, and Sauger Populations in Lake Sharpe, South Dakota written by Joseph H. Elrod and published by . This book was released on 1969 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catch-effort data derived from gill net samples were used to estimate relative abundance, age composition, sex ratio, growth rate, survival rate, and relative year-class strength of northern pike, walleye, and sauger populations in Lake Sharpe, Missouri, S.D., during the first three years of impoundment (1964-1966.). Catches were generally highest in Oahe Dam tailwaters. Females were more numerous and larger at most ages than males.

Age and Growth of Saginaw Bay Walleye with Observations on Trap Net Mortality and Population Size

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ISBN 13 :
Total Pages : 72 pages
Book Rating : 4.3/5 (129 download)

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Book Synopsis Age and Growth of Saginaw Bay Walleye with Observations on Trap Net Mortality and Population Size by : David Jon Borgeson

Download or read book Age and Growth of Saginaw Bay Walleye with Observations on Trap Net Mortality and Population Size written by David Jon Borgeson and published by . This book was released on 1990 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Synchronous Recruitment of Walleye in the Great Lakes and the Influence of Climate on Recruitment

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ISBN 13 :
Total Pages : 166 pages
Book Rating : 4.:/5 (426 download)

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Book Synopsis Synchronous Recruitment of Walleye in the Great Lakes and the Influence of Climate on Recruitment by : Samantha Lee Fedor

Download or read book Synchronous Recruitment of Walleye in the Great Lakes and the Influence of Climate on Recruitment written by Samantha Lee Fedor and published by . This book was released on 2008 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Current concerns about the repercussions of global climate change have stimulated efforts to understand how changing abiotic conditions influence natural populations. Walleye (Sander vitreus) populations have shown marked annual variability that can not be predicted by the size of the spawning population. Previous research has associated this variability with environmental factors such as spring warming rate, river discharge, and storm frequency and intensity. Frequently, however, the predictability of models developed from these studies falters as new data points are added and previous relationships are weakened. Relationships between recruitment and abiotic variables may disintegrate because of the interaction between local and large-scale variables that may not be detected in short time series but become more apparent when many more years are added. By comparing multiple populations within a region, the effects of large-scale variables and local variables should be possible to distinguish, with years of covariation representing years in which climate (or other large-scale factors) is influencing recruitment. We examined the effects of climate on recruitment of walleye by comparing four populations of walleye in the Great Lakes (west basin, Lake Erie, Saginaw Bay, Lake Huron, Green Bay, Lake Michigan, and Bay of Quinte, Lake Ontario) for synchrony of recruitment. Synchrony in recruitment among populations was determined using Pearson's product moment coefficient, and both single site and multi site models were created to test a set of a priori hypotheses regarding various local and large-scale factors influencing recruitment. Synchrony of recruitment occurred between three sites: west basin, Lake Erie, Green Bay, Lake Michigan, and Bay of Quinte, Lake Ontario during 2000-2004. El Niño-Southen Oscillation and the North Atlantic Oscillation were the best predictors of recruitment during 2000-2004. These results suggest that in addition to local weather conditions, large-scale factors influence walleye recruitment in the Great Lakes, and were the dominant variables influencing recruitment during this time. Understanding whether future changes in climate will cause overall increases or decreases in recruitment may help managers choose between more conservative and more liberal management strategies.

Population Dynamics of Age-0 Walleye in Western Lake Erie

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Publisher :
ISBN 13 :
Total Pages : 230 pages
Book Rating : 4.:/5 (18 download)

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Book Synopsis Population Dynamics of Age-0 Walleye in Western Lake Erie by : Sarah E. H. Bartnik

Download or read book Population Dynamics of Age-0 Walleye in Western Lake Erie written by Sarah E. H. Bartnik and published by . This book was released on 2005 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Legacies of Early-life Experiences on Individual, Cohort, and Population Performance of Lake Erie Walleye

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ISBN 13 :
Total Pages : 279 pages
Book Rating : 4.:/5 (129 download)

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Book Synopsis Legacies of Early-life Experiences on Individual, Cohort, and Population Performance of Lake Erie Walleye by : Leah Zoe Almeida

Download or read book Legacies of Early-life Experiences on Individual, Cohort, and Population Performance of Lake Erie Walleye written by Leah Zoe Almeida and published by . This book was released on 2021 with total page 279 pages. Available in PDF, EPUB and Kindle. Book excerpt: The experiences an individual has during early development may have life-long effects (“experiential legacies”) which can also have population-level consequences. However, since experiential legacies are difficult to measure in populations, how experiential legacies of individuals affect cohort- and population-level outcomes (i.e., buffering or amplifying population responses) remains difficult to discern. The objective of my dissertation research is to evaluate the extent to which experiential legacies affect individual performance and alter population dynamics. By exploring the importance of individual life events to populations, we can better understand the interconnectedness of life stages and better anticipate how environmental change may alter population and community dynamics. Specifically, I examined individual experiential legacies across a range of animal species with the goal of identifying generalizable patterns in response to early-life nutritional stress (Chapter 2), and then I focused on experiential legacies within individuals (Chapter 3), cohorts of individuals (Chapter 4), and a population consisting of multiple cohorts (Chapter 5) in Lake Erie Walleye (Sander vitreus). Lake Erie Walleye present a population for which understanding the long-term impacts of early-life experiences may be particularly valuable due to current human-induced environmental changes within its ecosystem. Since experiential legacies can produce unanticipated changes in the kinds as well as proportions of subsequent (i.e., later in life) phenotypes, examining patterns across multiple species may expose underlying trends. Patterns in experiential legacies across 81 studies of 65 animal species demonstrated generally consistent negative or neutral impacts of early nutritional stress on later-life phenotypes, indicative of energy depletion as a mechanism for the long-term consequences of early-life conditions (Chapter 2). Yet, overall, my results emphasize the existence of complicated interactions among a suite of phenotypic responses in determining individual performance. Within Lake Erie Walleye, I found evidence of experiential legacies from early-life experiences using laboratory experiments, but I also observed indications of the strong influence of maternal legacies and of carryover effects from more recent experiences using long-term data on cohorts. Nutritional quality of food during early life (a 10-d period starting when Walleye could first feed) was positively correlated with Walleye juvenile sizes and this correlation with size continued even after all treatments were fed on a high-quality standardized diet for an additional 27-d (Chapter 3). Beyond the period examined in my laboratory experiments, though, in an analysis of field data, I found that maternal effects were more influential than sizes or densities achieved during the first few months of life to annual growth in Walleye cohorts at ages 3-5 (Chapter 4). Thus, early-life experiences can produce experiential legacies in Lake Erie Walleye, but those experiences may be overwhelmed by the lingering influence of other factors such as maternal effects. Additionally, at the cohort-level, growth in the previous year negatively affected recent growth at ages 3-5, which may be indicative of compensatory growth in Walleye and could reduce variation among cohorts in size-at-age over a longer period of time. At the population-level, I modeled how specific experiential legacies may be more or less beneficial under different environmental conditions for Lake Erie Walleye, which demonstrates characteristics of a periodic life history (i.e., high fecundity, low early-life survival, old age at maturity), as well as for populations representing equilibrium (low fecundity, low early-life survival, old age at maturity) and opportunistic (high fecundity, low early-life survival, young age at maturity) life histories (Chapter 5). Across experiential legacies and these three life history strategies, early-life environments were primarily responsible for differences in simulated population growth rates and demography, with more frequent “good” early-life environments increasing population growth rates, increasing variation in population growth rates, and decreasing the proportion of older ages in the populations. However, when early-life environments were likely to be good and later-life environments were likely to be poor, experiential legacies that create lifetime trajectories (i.e., early-life conditions establish phenotypes that persist throughout life) were beneficial to population growth for all life histories. While other modeled experiential legacies did not demonstrate any specific benefit to Walleye, experiential legacies that create environmental specialization (i.e., later-life phenotypes perform best when early-life and later-life environments are similar) and later stressor resilience (i.e., poor early-life environments allow later-life phenotypes to perform well in poor environments) were beneficial for the equilibrium population when early-life environments were frequently poor, potentially due to the importance of adult survival for the equilibrium population. Overall, these simulations indicated that variation in experiential legacies across populations could be due to combinations of life history characteristics and frequencies of specific environmental conditions in early and later life. My results at the individual, cohort, and population level demonstrate how exploring experiential legacies can provide a deeper understanding of population patterns. Across species, experiential legacies may be related to how energy is allocated in early life (Chapter 2). Within Lake Erie Walleye, I observed that early-life nutritional conditions continued to affect juvenile Walleye sizes after nutritional conditions became standardized, supporting the idea of early-life energy allocation driving later performance (Chapter 3). Despite these results in young Walleye, the early-life growth environment did not appear to be the most important factor driving later cohort-based Walleye growth, potentially due to compensatory growth maintaining stable size-at-age and maternal provisioning legacies (Chapter 4). Regardless of the experiential legacy that Lake Erie Walleye or other species experience, the early-life environment appears to be extremely influential in driving population growth; however, certain experiential legacies may be more common in specific environmental scenarios for species with specific life histories due to the potential advantages those experiential legacies provide (Chapter 5). While many questions remain, my research has improved our understanding of patterns and implications of experiential legacies in general, as well as the degree to which legacies of early life influence the response of Lake Erie Walleye to its environment.

Responses of an Exploited Fish Population to Environmental Change

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Publisher :
ISBN 13 :
Total Pages : 398 pages
Book Rating : 4.:/5 (129 download)

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Book Synopsis Responses of an Exploited Fish Population to Environmental Change by : David Arthur Dippold

Download or read book Responses of an Exploited Fish Population to Environmental Change written by David Arthur Dippold and published by . This book was released on 2020 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dynamics of fish populations are determined by demographic processes such as growth, survival, mortality, and movement that are influenced directly and indirectly by a suite of biotic and abiotic factors. Human-induced environmental change (e.g., climate change, nutrient pollution) is altering these processes, influencing the ability of ecosystems to support their resident populations, as well as the valuable ecosystem services they provide. The impacts of human-induced environmental change are often negative, can occur at a variety of spatial and temporal scales, and can vary with ontogeny. Therefore, understanding the historical and anticipated effects of environmental change on the dynamics of fish populations is critical to maintaining them, including the valued services and fisheries that they support. My research has sought to better understand the factors that influence population-level responses of exploited fish populations to changing environmental conditions, and to anticipate what these responses may look like amidst future change. To help achieve this research goal, my collaborators and I developed and applied numerous quantitative approaches to economically and ecologically important Lake Erie fish populations. Specifically, we forecasted the recruitment dynamics of several fish populations (walleye Sander vitreus, yellow perch Perca flavescens, and white perch Morone americana) under future climate change scenarios (Chapter 2), investigated historical changes in walleye recruitment dynamics in response to environmental factors (Chapter 3), anticipated how environmental change might alter early-life growth and survival of walleye via changes in larval stage duration (Chapter 4), and identified the role of demographic and environmental factors on the spatial patterning of walleye recreational harvest rates in Lake Erie (Chapter 5). These studies demonstrate that the dynamics of Lake Erie’s fish populations have changed in the past, and that environmental change is likely to continue to alter the dynamics of Lake Erie’s fish populations in the future. In Chapter 2, our modeling showed that walleye and yellow perch recruitment were forecasted to decline under future climate change, owing to shorter and warmer winters. For yellow perch, these declines were projected to be exacerbated by the implementation of agricultural conservation practices that reduce nutrient inputs into the west basin of Lake Erie. By contrast, recruitment of invasive white perch was projected to remain stable or increase relative to the past. In Chapter 3, my colleagues and I developed a modeling framework to build more informative environment-recruitment models. By applying this framework to the Lake Erie walleye population, we determined that the timing and importance of environmental factors previously associated with walleye recruitment (e.g., winter severity, spring warming rate, river discharge) have likely changed in the recent past. In Chapter 4, we linked output from a physical model to a bioenergetics model to show that walleye larval stage duration has likely changed in the recent past, with significant differences in direction and magnitude among Lake Erie’s three basins. Using historical environmental variability, we anticipated how future climate change might affect early-life growth and survival. Finally, in Chapter 5, my colleagues and I demonstrated that the relationships between temperature and walleye population size and recreational harvest rates vary spatially, and we anticipated how future ecosystem change could necessitate changes to the management of walleye in Lake Erie, owing to this spatial dependency. Collectively, the results of my research have helped to understand how Lake Erie’s fish populations respond to environmental change, to the benefit of fisheries management.

Walleye Wisdom

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Publisher : Outdoor Sportsman Group
ISBN 13 : 9780960525416
Total Pages : 300 pages
Book Rating : 4.5/5 (254 download)

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Book Synopsis Walleye Wisdom by : Al Lindner

Download or read book Walleye Wisdom written by Al Lindner and published by Outdoor Sportsman Group. This book was released on 1983 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: A complete guide to fishing walleyes anywhere from St. Lawrence to the Columbia River, and from the Canadian north to the canyon reservoirs of the Southwest.

Lake Erie Walleye Population Structure and Stock Discrimination Methods

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ISBN 13 :
Total Pages : 150 pages
Book Rating : 4.:/5 (976 download)

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Book Synopsis Lake Erie Walleye Population Structure and Stock Discrimination Methods by : Kuan-Yu Chen

Download or read book Lake Erie Walleye Population Structure and Stock Discrimination Methods written by Kuan-Yu Chen and published by . This book was released on 2016 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Both natal philopatry and deviations from natal philopatry (i.e., straying) can play important roles in persistence of migratory populations. While natal philopatry allows for isolation among local breeding populations and the opportunity for local adaptation, straying may provide rescue effects to declining local populations or colonization of new habitats. However, quantification of natal philopatry can be challenging because the migratory behavior and variability therein itself makes tracking individual movement across years difficult. In turn, a key advance that could help narrow this knowledge gap is the development of “markers” that can reliably discriminate among local populations so that homing and straying behavior can be quantified. The central goal herein is to evaluate existing methods and develop appropriate markers for determining natal origins and measuring connectivity among local spawning populations (or spawning stocks) of walleye (Sander vitreus) in western Lake Erie. Toward this end, we selected two commonly-used natural markers, otolith microchemistry and genetics, to quantify natal philopatry and understand population structure and dynamics of the Lake Erie walleye. While otolith microchemistry records the elemental fingerprints of natal origins of individuals, genetic markers can ascertainpopulation membership of individuals owing to divergence of local populations. We expected that if walleye show strong natal philopatry (revealed by otolith microchemistry), population structure could exist among the spawning stocks because natal philopatry is a potential mechanism that drives reproductive isolation. If so, we could also use genetic markers to determine the source stocks of individuals among the stocks, particularly in which otolith elemental fingerprints are undistinguishable. In this study, we first evaluated whether otolith strontium concentration [Sr] can be used as a natural marker to discriminate individuals spawned between two river-spawning sites using both lab-reared and field-collected walleye larvae (Chapter 2). Next, we applied the marker, otolith [Sr], to quantify natal philopatry of adult walleye among the two river-spawning and one reef-spawning sites (Chapter 3). Toward developing genetic stock discrimination markers, we developed an analytical toolkit that allows us to perform assignment tests and evaluate how different factors (i.e., population differentiation, sample sizes of individual and loci) could influence assignment results (Chapter 4). It can help ascertain population membership of individuals and determine whether our data is sufficient to discriminate among populations. Our findings revealed that spawning walleye had high natal homing rates, with about 98% of individuals returning to the natal site to spawn based on the evidences of otolith microchemistry, but the genetic markers (i.e., thousands of SNP loci) did not have enough discriminatory power to ascertain population membership of individuals. The overall correct assignment rates estimated using sole genetic data were only better than random assignment, even though the rates can be improved by integrating genetic and otolith microchemistry data (Appendix A). These results suggested that the connectivity among the walleye spawning stocks might be weak, but the stocks still reflect a weakly differentiated population and hence we were unable to use the newly developed genetic loci as the stock discrimination marker. Despite its insignificant population structure, strong natal homing behavior indicated that they form reproductively isolated stocks and therefore should be managed as separated stocks.

Lake Erie Walleye

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Publisher :
ISBN 13 : 9780964330917
Total Pages : 0 pages
Book Rating : 4.3/5 (39 download)

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Book Synopsis Lake Erie Walleye by : Mark Hicks

Download or read book Lake Erie Walleye written by Mark Hicks and published by . This book was released on 1996-03 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Temporal and Spatial Genetic Consistency of Walleye (Sander Vitreus) Spawning Groups

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ISBN 13 :
Total Pages : 54 pages
Book Rating : 4.:/5 (786 download)

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Book Synopsis Temporal and Spatial Genetic Consistency of Walleye (Sander Vitreus) Spawning Groups by : Jo Ann Banda

Download or read book Temporal and Spatial Genetic Consistency of Walleye (Sander Vitreus) Spawning Groups written by Jo Ann Banda and published by . This book was released on 2011 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: The population genetic structure of three of the largest walleye spawning groups in Lake Erie is tested for consistency over time and space spanning 14 years, based on nine high-resolution nuclear DNA microsatellite loci. Previous genetic studies focused on a one-time genetic "snapshot", with an earlier study by our laboratory finding that the genetic structure of three Lake Erie spawning groups along the southern shore - Maumee River, Sandusky River, and Van Buren Bay reefs - appeared similar in 2003, whereas most other spawning groups across Lake Erie were genetically distinctive. The present study analyzes the stability of genetic similarity patterns within and among 726 walleye spawning at these three sites across years and age cohorts in 1995, 1998, 2003, 2007, and 2008. Genetic patterns are evaluated using pairwise FST analog and contingency tests, AMOVA partitioning, and Bayesian assignment tests. Results reveal overall year-to-year consistency in genetic structure of walleye spawning at the three sites, with some annual variation in the Van Buren Bay reef group. Greater genetic divergence from the other groups is detected in the Van Buren Bay spawning group, which reflects greater geographic separation. Walleye spawning in the Sandusky and Maumee Rivers are genetically distinguishable from each other when data from all years are combined, which suggests possible sample size effect (i.e., annual sample sizes likely were not large enough to detect their genetic differentiation). No significant differences occur among age cohorts, between the sexes, or among sampling dates within spawning runs. Results demonstrate the importance of sampling over several years of walleye spawning runs in order to resolve fine-scale genetic relationships within an open lake system.