Download or read book Lower Trophic Level and Climate Influences on Western Lake Erie Fish Recruitment 1988 2005 written by Valerie C. Crane and published by . This book was released on 2007 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The recruitment of yellow perch and walleye in the western basin of Lake Erie is highly variable, both spatially and from year-to-year. For this reason, we examined the impact of weather and lower trophic level factors on the year--class formation of these species for the period from 1988 to 2005. We hypothesized that the temporal and spatial match/mismatch of the age-0 fish with their zooplankton prey would influence year-class strength (YCS). We split our YCS and plankton data into four western basin habitat areas (island area, west of island area, Maumee Bay, and the Sandusky subbasin) and used multiple regression analysis with Akaike's information criterion for model selection to identify the most important factors influencing recruitment. We found that the relative influence of lower trophic level factors differed by area, with zooplankton variables being more important in the less productive areas. Weather factors, however, were important in all areas. Previous winter temperature was found to be very important in shaping the year-classes of both of these percids. Of the lower trophic level variables, the date of the midseason crustacean zooplankton decline and May copepod productivity (u/L/day) were the most important factors in yellow perch recruitment, while May cladoceran productivity and May percent Daphnia were most important in walleye recruitment. We also found that there was often a switch from a positive relationship with zooplankton productivity in May to a negative relationship in June, suggesting that YCS is set early and large numbers of YOY fish can exert top-down control over the zooplankton community, depressing productivity early in the season. Our results show that even within the same system, spatial differences in habitat can lead to different recruitment mechanisms. Because little is known about the recruitment of forage fish in Lake Erie, we also attempted to identify factors that are influential to the recruitment of several forage species (white bass, white perch, freshwater drum, emerald and spottail shiners, gizzard shad, trout perch, and rainbow smelt). We constructed regression models for the whole western basin and attempted to identify factors that influence recruitment on a basin-wide scale rather than identifying spatial differences as we did for yellow perch and walleye. All variables were, however, averaged by area to account for area-specific differences in our models. We found that forage fish recruitment, while less variable than yellow perch and walleye recruitment, did show large amounts of interannual variation. In addition, some species such as white perch showed trends in recruitment, with YCS decreasing and then leveling off over our time series. As with yellow perch and walleye, lower trophic level and weather factors were important to the recruitment of forage fish. For example, early season zooplankton productivity and wind speed and direction were important to several forage species. However, we found that while previous winter air temperature influenced yellow perch and walleye recruitment, spring and summer air temperatures were more influential in the recruitment of forage species. We also found that adult population size was positively related to white perch recruitment and predation by age-O walleyes was negatively related to shiner recruitment. We uncovered several similarities and differences in the recruitment mechanisms of forage species and some species exhibited year-to-year recruitment synchrony, which we attributed to similarities in habitat use. However, these similarities were not always captured in our models and we suggest that more research on forage fish recruitment is necessary in the Great Lakes.
Download or read book Canadian Journal of Fisheries and Aquatic Sciences written by and published by . This book was released on 2014-05 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book EcoLE FisH written by Aparna Sathyanarayan and published by . This book was released on 2007 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: EcoLE-Fish, an ecological model of Lake Erie with fish and human interactions, was constructed on top of EcoLE (Zhang 2006 [60]), which, in turn, was based on the Boegman et al. 2001 [4] adaptation of the U.S. Army Corps of Engineers' CE-QUAL-W2. EcoLE-FisH is a two-dimensional hydrodynamic model of Lake Erie that incorporates the dynamics of the physcial, chemical, and lower trophic level components, in addition to those of adult and young-of-year walleye, sport and commercial fishing, and the management of the walleye fishery. All sub-models (except recruitment) were calibrated against observed data for 1.997 and verified for 1998 and 1999; the recruitment sub- model was calibrated against the recruitment in 1999, and verified against that in 2000. Once the model was tailored to Lake Erie, the model framework was used to explore the recruitment process. Average daily mortality of lake-spawned eggs was 5.36-6.21%, that of river-spawned eggs was 4.47-6.44%, that of lake larvae was 1.86-10.04%, that of river larvae was 0.78-3.45% and that of juveniles was 0.41-0.81%. While eggs typically experienced lowest survival, the larval stage was crucial in determining year-class strength in some years, while the juvenile stage was pivotal in other years. Low pre-spawning temperatures increased recruitment by 65% in 1999 and by 23% in 2000; there was a greater impact on the western basin stocks than on the eastern basin stock, the larval stage was the most responsive to thermal change, and there was evidence of a delayed effect on the recruitment of the successive year class. Faster warming rates, associated with low pre-spawning temperatures, were correlated with the increased survival of young-of-year. High pre-spawning temperatures increased the recruitment by 6% in 1999 reduced it by 10% in 2000; the impact on the eastern basin stock was much larger than on the western basin stocks, though this should be viewed with caution as the spawning grounds of the eastern basin stock are located in the deep waters of the eastern basin (as necessitated by the two-dimensional nature of the model), where small changes in temperature can have tremendous impacts. Food availability did not influence the recruitment process, and the absence of hydrodynamic transport of eggs and larvae reduced recruitment by 8% in 1999 and increased it by 2% in 2000, indicating that hydrodynamics can have both positive and negative effects, depending on prevailing physical conditions.
Download or read book Impacts of climate change on fisheries and aquaculture written by Food and Agriculture Organization of the United Nations and published by Food & Agriculture Org.. This book was released on 2019-01-06 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report indicates that climate change will significantly affect the availability and trade of fish products, especially for those countries most dependent on the sector, and calls for effective adaptation and mitigation actions encompassing food production.
Download or read book Lipids in Freshwater Ecosystems written by Michael T. Arts and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fundamental purpose of this book is to synthesise the divergent literature on aquatic lipids into a co-ordinated, digestible form. A large part of the book addresses lipid composition and production in freshwater organisms, with chapters on phytoplankton, zooplankton and benthic invertebrates. A common theme throughout the book is the function of lipids in aquatic food webs, with a chapter devoted exclusively to lipids as indicators of health in fish populations. A complementary chapter highlights the role of lipids and essential fatty acids in mariculture. Methodologies to determine the lipid content of aquatic samples and suggestions as to the utility of fatty acids as trophic markers are included, as is one chapter on the role of lipids in the bioaccumulation and bioconcentration of toxicants and another on the relationships between lipids and surface films and foams. The final chapter highlights the similarities and differences between lipids of marine and freshwater origin. Students and researchers in ecology, phycology, aquatic toxicology, physiological ecology and limnology will find this an invaluable guide and reference.
Download or read book Global Change and River Ecosystems Implications for Structure Function and Ecosystem Services written by R. Jan Stevenson and published by Springer. This book was released on 2015-03-21 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rivers around the world are threatened by changes in land use, climate, hydrologic cycles, and biodiversity. Global changes in rivers include, but are not restricted to water flow interruptions, temperature increases, loss of hydrological connectivity, altered water residence times, changes in nutrient loads, increasing arrival of new chemicals, simplification of the physical structure of the systems, occurrence of invasive species, and biodiversity losses. All of them affect the structure and functioning of the river ecosystem, and thereby, their ecosystem services. Understanding the responses of river ecosystems and their services to global change is essential for protecting human well being in all corners of the planet. Rivers provide critical benefits by providing food from fisheries and irrigation, regulating biogeochemical balances, and enriching our aesthetic and cultural experience. Predicting responses of rivers to global change is challenged by the complexity of interactions among these man-made drivers across a mosaic of natural hydrogeomorphic and climatic settings. This book explores the broad range of determinants defining global change and their effects on river ecosystems. Authors have provided thoughtful and insightful treatments of specific topics that relate to the broader theme of global change regulation of river ecosystems.
Download or read book Ecological Effects of Water level Fluctuations in Lakes written by Karl M. Wantzen and published by Springer Science & Business Media. This book was released on 2009-05-06 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most aquatic ecosystems have variable water levels. These water-level fluctuations (WLF) have multiple effects on the organisms above and below the waterline. Natural WLF patterns in lakes guarantee both productivity and biodiversity, while untimely floods and droughts may have negative effects. Human impacts on WLF have led to a stabilization of the water levels of many lakes by hydraulic regulation, untimely drawdown due to water use, or floods due to water release from hydropower plants in the catchments. This book provides a first review in this field. It presents selected papers on the ecological effects of WLF in lakes, resulting from a workshop at the University of Konstanz in winter 2005. Issues addressed here include the extent of WLF, and analyses of their effects on different groups of biota from microorganisms to vertebrates. Applied issues include recommendations for the hydrological management of regulated lakes to reduce negative impacts, and a conceptual framework is delivered by an extension of the floodpulse concept for lakes. Current impacts on water use, including increasing demands on drinking and irrigation water, hydropower etc., and climate change effects on WLF make this book an essential resource for aquatic ecologists, engineers, and decision-makers dealing with the management of lake ecosystems and their catchments.
Download or read book The Potential Effects of Global Climate Change on the United States written by and published by . This book was released on 1989 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Circulation in the Coastal Ocean written by G.T. Csanady and published by Springer Science & Business Media. This book was released on 1982-09-30 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: For some time there has existed an extensive theoretical literature relating to tides on continental shelves and also to the behavior of estuaries. Much less attention was traditionally paid to the dynamics of longer term, larger scale motions (those which are usually described as circulation') over continental shelves or in enclosed shallow seas such as the North American Great Lakes. This is no longer the case: spurred on by other disciplines, notably biological oceanography, and by public concern with the environment, the physical science of the coastal ocean has made giant strides during the last two decades or so. Today, it is probably fair to say that coastal ocean physics has come of age as a deduc tive quantitative science. A well developed body of theoretical models exist, based on the equations of fluid motion, which have been related to observed currents, sea level variations, water properties, etc. Quantitative parameters required in using the models to predict e.g. the effects of wind or of freshwater influx on coastal currents can be estimated within reasonable bounds of error. While much remains to be learned, and many exciting discoveries presumably await us in the future, the time seems appropriate to summarize those aspects of coastal ocean dynamics relevant to 'circulation' or long term motion.
Download or read book Climate Change and Water written by Intergovernmental Panel on Climate Change / Working Group Technical Support Unit and published by . This book was released on 2008 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Technical Paper addresses the issue of freshwater. Sealevel rise is dealt with only insofar as it can lead to impacts on freshwater in coastal areas and beyond. Climate, freshwater, biophysical and socio-economic systems are interconnected in complex ways. Hence, a change in any one of these can induce a change in any other. Freshwater-related issues are critical in determining key regional and sectoral vulnerabilities. Therefore, the relationship between climate change and freshwater resources is of primary concern to human society and also has implications for all living species. -- page vii.
Download or read book Lake Erie and Lake St Clair Handbook written by S. J. Bolsenga and published by Wayne State University Press. This book was released on 1993 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: Learn about the wonders of Lake Erie and Lake St. Clair in this fascinating and readable book. The most comprehensive reference source available about the lakes, Lake Erie and Lake St. Clair Handbook is an ideal guide for anglers, boaters, swimmers, beach walkers—anyone who uses and enjoys the lakes. The handbook explains, in simple terms, the reasons for the scenic beauty and the natural events that occur in the coastal and offshore waters of Lake Erie and Lake St. Clair, including the St. Clair, Detroit, and Niagara rivers extending from Sarnia, Ontario, to Niagara-on-the-Lake, New York. Individual chapters focus on the land, air, water, and life forms that comprise the natural history and environment of the region—the shoreline topography, wind and weather patterns, water temperature cycles and water level changes, the ecology, and indigenous animal life. Lake Erie and Lake St. Clair Handbook enhances our understanding and appreciation of the lakes and their surroundings by addressing fundamental questions about the Lake Erie region: • how Lake Erie was formed through glacial processes • why daily and seasonal weather patterns occur • causes of the water currents and waves • causes of temperature patterns in the lakes • the location of productive reef features • the species of fish and birds found in the area • the importance of the wetlands • the effect of current and past pollution on the aquatic life in the lakes
Download or read book Facing Marine Deoxygenation written by Arthur Capet and published by Frontiers Media SA. This book was released on 2020-03-09 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book UV Effects in Aquatic Organisms and Ecosystems written by E Walter Helbling and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers extensive coverage of the most important aspects of UVR effects on all aquatic (not just freshwater and marine) ecosystems, encompassing UV physics, chemistry, biology and ecology. Comprehensive and up-to-date, UV Effects in Aquatic Organisms and Ecosystems aims to bridge the gap between environmental studies of UVR effects and the broader, traditional fields of ecology, oceanography and limnology. Adopting a synthetic approach, the different sections cover: the physical factors controlling UVR intensity in the atmosphere; the penetration and distribution of solar radiation in natural waters; the main photochemical process affecting natural and anthropogenic substances; and direct and indirect effects on organisms (from viruses, bacteria and algae to invertebrate and vertebrate consumers). Researchers and professionals in environmental chemistry, photochemistry, photobiology and cell and molecular biology will value this book, as will those looking at ozone depletion and global change.
Download or read book Ecosystems of California written by Harold Mooney and published by Univ of California Press. This book was released on 2016-01-19 with total page 1008 pages. Available in PDF, EPUB and Kindle. Book excerpt: This long-anticipated reference and sourcebook for CaliforniaÕs remarkable ecological abundance provides an integrated assessment of each major ecosystem typeÑits distribution, structure, function, and management. A comprehensive synthesis of our knowledge about this biologically diverse state, Ecosystems of California covers the state from oceans to mountaintops using multiple lenses: past and present, flora and fauna, aquatic and terrestrial, natural and managed. Each chapter evaluates natural processes for a specific ecosystem, describes drivers of change, and discusses how that ecosystem may be altered in the future. This book also explores the drivers of CaliforniaÕs ecological patterns and the history of the stateÕs various ecosystems, outlining how the challenges of climate change and invasive species and opportunities for regulation and stewardship could potentially affect the stateÕs ecosystems. The text explicitly incorporates both human impacts and conservation and restoration efforts and shows how ecosystems support human well-being. Edited by two esteemed ecosystem ecologists and with overviews by leading experts on each ecosystem, this definitive work will be indispensable for natural resource management and conservation professionals as well as for undergraduate or graduate students of CaliforniaÕs environment and curious naturalists.
Download or read book Centrarchid Fishes written by Steven Cooke and published by John Wiley & Sons. This book was released on 2009-09-08 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt: Centrarchid fishes, also known as freshwater sunfishes, include such prominent species as the Largemouth Bass, Smallmouth Bass and Bluegill. They are endemic to Eastern North America where they form part of a multi-million dollar sports fishing industry, but they have also been widely introduced around the globe by recreational anglers, in aquaculture programs and by government fisheries agencies. Centrarchid Fishes provides comprehensive coverage of all major aspects of this ecologically and commercially important group of fishes. Coverage includes diversity, ecomorphology, phylogeny and genetics, hybridization, reproduction, early life history and recruitment, feeding and growth, ecology, migrations, bioenergetics, physiology, diseases, aquaculture, fisheries management and conservation. Chapters have been written by well-known and respected scientists and the whole has been drawn together by Professors Cooke and Philipp, themselves extremely well respected in the area of fisheries management and conservation. Centrarchid Fishes is an essential purchase for all fish biologists, ecologists, fisheries managers and fish farm personnel who work with centrarchid species across the globe.
Download or read book Assessing the Hypoxia Threat in U S Coastal Waters written by William Jacobs and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The occurrence of hypoxia, or low dissolved oxygen, is increasing in coastal waters world-wide and represents a significant threat to the health and economy of our Nation's coasts and Great Lakes. This trend is exemplified most dramatically off the coast of Louisiana and Texas, where the second largest eutrophication-related hypoxic zone in the world is associated with the nutrient pollutant load discharged by the Mississippi and Atchafalaya Rivers. Aquatic organisms require adequate dissolved oxygen to survive. The term "dead zone" is often used in reference to the absence of life from habitats that are devoid of oxygen. The inability to escape low oxygen areas makes immobile species, such as oysters and mussels, particularly vulnerable to hypoxia. This book examines the progress in understanding the dynamics of hypoxia where it occurs; understanding monitoring nutrient fluxes in watersheds; and how to reduce nutrient transport across the landscape.
Download or read book A Handbook of Global Freshwater Invasive Species written by Robert A. Francis and published by Routledge. This book was released on 2012-03-12 with total page 918 pages. Available in PDF, EPUB and Kindle. Book excerpt: Invasive non-native species are a major threat to global biodiversity. Often introduced accidentally through international travel or trade, they invade and colonize new habitats, often with devastating consequences for the local flora and fauna. Their environmental impacts can range from damage to resource production (e.g. agriculture and forestry) and infrastructure (e.g. buildings, road and water supply), to human health. They consequently can have major economic impacts. It is a priority to prevent their introduction and spread, as well as to control them. Freshwater ecosystems are particularly at risk from invasions and are landscape corridors that facilitate the spread of invasives. This book reviews the current state of knowledge of the most notable global invasive freshwater species or groups, based on their severity of economic impact, geographic distribution outside of their native range, extent of research, and recognition of the ecological severity of the impact of the species by the IUCN. As well as some of the very well-known species, the book also covers some invasives that are emerging as serious threats. Examples covered include a range of aquatic and riparian plants, insects, molluscs, crustacea, fish, amphibians, reptiles and mammals, as well as some major pathogens of aquatic organisms. The book also includes overview chapters synthesizing the ecological impact of invasive species in fresh water and summarizing practical implications for the management of rivers and other freshwater habitats.
