Download or read book Movement of Atlantic Cod Gadus Morhua in and Among the Western Gulf of Maine Rolling Closures as Determined Through Mark and Recapture written by Michael Morin and published by . This book was released on 2003 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spawning Dynamics Seasonal Movements and Population Structure of Atlantic Cod Gadus Morhua in the Gulf of Maine written by Douglas Robert Zemeckis and published by . This book was released on 2016 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atlantic cod (Gadus morhua) have been a principal target species in New England's ground fish fishery since the 17th century. In recent decades, the Gulf of Maine cod stock has experienced substantial declines in abundance, and many historical spawning components have been depleted, reducing stock productivity and stability. Managing stock rebuilding has been difficult because of many uncertainties in population dynamics. Therefore, to support stock rebuilding efforts, the objective of this dissertation was to improve our understanding of the spawning dynamics, seasonal movements, and population structure of Atlantic cod in the Gulf of Maine. An interdisciplinary review of the scientific literature demonstrated that the cod population off New England can be described as a metapopulation that includes genetically-distinct spring- and winter spawning subpopulations which are comprised of many finer-scale spawning components. Available information indicates that current management unit boundaries do not accurately represent the biological population structure. Therefore, a modification of current management units is recommended to provide a more accurate representation of the underlying biological population processes. Review of the cod spawning literature indicated that cod spawn in multiple locations and seasons, and the complex cod mating system can be described as a "lek". The aspects of cod spawning dynamics most important for consideration by fishery managers are the spatial and temporal extent ofspawning, the behavior of spawners, and the reproductive contributions of older age-classes. The application of spawning closures as part of a multidisciplinary approach to fisheries management is recommended to prevent disruption of spawning and extirpation of semi-discrete spawning components. Spawning site fidelity contributes to the formation and maintenance of the observed metapopulation structure and delays the recolonization of abandoned spawning sites by limiting reproductive connectivity. Acoustic telemetry was used to document prevalent, fine-scale spawning site fidelity with respect to an inshore spawning site in the western Gulf of Maine. Movements away from the inshore spawning site were studied using conventional tags, acoustic telemetry, and geolocation utilizing data from archival data storage tags. Connectivity was documented among multiple inshore spawning sites, which is apparently sufficient to promote gene flow within the western subpopulation. Cod were primarily residential within the western Gulf of Maine. After spawning inshore, cod moved to offshore feeding grounds from summer to early winter. Deep offshore basins served as overwintering habitat before initiation of an inshore spring spawning migration. Results from this dissertation have been valuable for informing fishery managers in the development of regulations to protect cod spawning aggregations. Findings are contributing to ongoing processes to investigate cod population structure and reevaluate current management units. This dissertation provides a more holistic understanding of cod population dynamics, which is expected to contribute to the development of future fishery management plans and stock assessment models that work towards achieving stock rebuilding.
Download or read book Movements of Atlantic Cod Gadus Morhua in NAFO Subdiv 3Ps and Updated Estimates of Exploitation from Tagging Experiments in 1997 2002 written by and published by . This book was released on 2002 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A mark-recapture study of Atlantic cod, initiated off southern Newfoundland in 1997, was continued in 2002. The purpose of the study was to provide information on movement patterns of inshore & offshore cod and to obtain estimates of exploitation rates on different components of the stock. This report presents annual estimates of exploitation for each tagging experiment during 1997-2002 and summarizes the spatial & temporal distribution of recaptures of tagged cod released in various regions of the south coast during 1997-2002 and reported as recaptured up to the end of September 2002. The report also illustrates the distribution of recaptures from tagging.
Download or read book Environmental Assessment for an Interim Action to Implement Gulf of Maine Atlantic Cod Mortality reduction Area Closures and Other Conservation Management Measures written by Brett Michael Alger and published by . This book was released on 2014 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This Environmental Assessment evaluates the impacts on the human environment for an action that would: Replace the Gulf of Maine Rolling Closures with several seasonal 30-minute grids in the Gulf of Maine (GOM) Broad Stock Area (BSA). These Seasonal Interim Closure Areas would be closed to federally permitted vessels using commercial and recreational gear capable of catching cod (see Figure 4). Implement a GOM cod trip limit of 200 lb for sector vessels fishing in the remaining open areas of the broad stock area. The common pool trip limit would be reduced to 200 lb per trip. Prohibit possession of recreationally caught GOM cod. Restrict commercial limited access groundfish vessels that fish in the GOM BSA to fishing only in that broad stock area for the duration of the declared trip"--Executive summary (page 1).
Download or read book The 2008 Assessment of the Gulf of Maine Atlantic Cod Gadus Morhua Stock written by Ralph K. Mayo and published by . This book was released on 2009 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Between patch Movement Behaviour of Juvenile Atlantic Cod gadus Morhua written by Mary R. Ryan and published by . This book was released on 2009 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Behaviors Habitat Preferences and Ecology of Distinct Atlantic Cod Phenotypes in the Gulf of Maine written by Christian W. Conroy and published by . This book was released on 2016 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diversity in spatial behaviors and associated divergence of phenotypes are common across fish taxa. Behavior and phenotype are shaped by geology, oceanography, climate, prey availability, predation, competition, and the cumulative effects of these factors on past generations. In stochastic natural systems, diversity may enhance stability, resilience, and even productivity of populations and population complexes. Among the behaviors of fish that vary between and within populations is migration. Migration is most often related to travel between spawning and feeding grounds and is integral to population productivity. However, members of the same species and even population may adopt vastly different migratory strategies, including long-distance migration and strict site residence. Across taxa, these strategies are often correlated with metabolism, growth, fecundity, and productivity. In the context of fisheries management, the spatial and physiological variance associated with different migratory strategies may lead to complicated or unexpected responses by managed stocks to disturbance. Understanding the processes that lead to the adoption and maintenance of migratory strategies, how these behaviors affect habitat use, and how behavior and habitat are related to phenotype, are necessary to the development of effective fisheries management policies and regulations. Atlantic cod (Gadus morhua) adopt a range of spatial behaviors across the North Atlantic, with effects on productivity and growth. As in other fish taxa, resident cod have lower growth rates and fecundity than conspecific migrants. Many identified groups of cod residents are physically isolated from nearby migrants, offering little insight to many of the important questions surrounding these behavioral strategies. In the Gulf of Maine, sympatric resident and migrant cod have been identified from a number of locations. This research focused on the interactions between behavior, habitat use, and phenotype of cod in the Gulf of Maine. A visually distinct cod phenotype found at several locations throughout the region features red pigmentation and a deeper body than the familiar form of cod. As is observed elsewhere in the species range, this red phenotype remains in relatively shallow, structured habitats and grows at lower rates compared to the familiar migrant olive phenotype. The connection between low growth, resident behavioral strategy, and body morphology (deep vs. fusiform) has been observed in a number of salmonids and may be common among fishes that occupy diverse environments. Red phenotypes were highly selective of certain habitats, and the spatial behaviors of all cod regardless of phenotype changed seasonally, possibly due to the influence of seasonal changes in environmental conditions like temperature. Phenotype-specific behaviors were consistent both inshore and offshore, generally following resident and migrant strategies. Offshore red phenotypes expressed strict site fidelity, but this may in part be due to habitat limitation, as nearshore red phenotypes adhered to shallow depths but moved up and down the coast. Regardless of phenotype, cod utilize shallow, structured habitats at an offshore site, Cashes Ledge, during the warm periods of the summer and fall. Habitat use is focused on the most complex habitats in the shallowest peaks of the ledge, which often are covered in thick macroalgal stands. The shallow structured habitats preferred by red phenotypes and utilized by all cod are not available to widely used groundfishing gear, thus limiting fishing pressure on these important habitats. At the same time, shallow coasts and ledges will be affected by warming surface waters and increased storm activities associated with ongoing climate change. The importance of these habitats and their utilization by cod relative to their adopted migratory strategies may impact population-scale responses of cod to future management activities.
Download or read book Effects of Fluctuations in Stock Abundance Upon Life History Parameters of Atlantic Cod Gadus Morhua L for the 1970 1987 Year Classes from Georges Bank and the Gulf of Maine written by Loretta O'Brien and published by . This book was released on 1990 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fishers Knowledge in Fisheries Science and Management written by Nigel Haggan and published by United Nations Educational, Scientific & Cultural Organization. This book was released on 2007 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drawing on a number of case studies from around the world, this publication considers how the local knowledge and practices of indigenous fishing communities are being used in collaboration with scientists, government managers and non-governmental organisations to establish effective frameworks for sustainable fisheries science and management. It seeks to contribute towards achieving the goal of establishing international responsibility for the ethical collection, preservation, dissemination and application of fishers' knowledge.
Download or read book Dynamics of Marine Ecosystems written by K. H. Mann and published by John Wiley & Sons. This book was released on 2013-04-16 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: The new edition of this widely respected text providescomprehensive and up-to-date coverage of the effects ofbiological–physical interactions in the oceans from themicroscopic to the global scale. considers the influence of physical forcing on biologicalprocesses in a wide range of marine habitats including coastalestuaries, shelf-break fronts, major ocean gyres, coral reefs,coastal upwelling areas, and the equatorial upwelling system investigates recent significant developments in this rapidlyadvancing field includes new research suggesting that long-term variability inthe global atmospheric circulation affects the circulation of oceanbasins, which in turn brings about major changes in fish stocks.This discovery opens up the exciting possibility of being able topredict major changes in global fish stocks written in an accessible, lucid style, this textbook isessential reading for upper-level undergraduates and graduatestudents studying marine ecology and biological oceanography
Download or read book Development of Fishery Statistics in the North Atlantic written by George Armytage Rounsefell and published by . This book was released on 1948 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book North Pacific Workshop on Stock Assessment and Management of Invertebrates written by Canada. Department of Fisheries and Oceans. Pacific Region and published by Department of Fisheries and Oceans, Information and Publications Branch. This book was released on 1986 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: Various papers are presented on the topics of invertebrate management ingeneral; the sampling of adults, juveniles and larval forms;population dynamics and models; exploration and multispecies interactions;and management strategies. An overall workshop summary is included.
Download or read book Marine Genetics written by Antonio M. Solé-Cava and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our current knowledge of marine organisms and the factors affecting their ecology, distribution and evolution has been revolutionised by the use, in the last 20 years, of molecular population genetics tools. This book is the result of a meeting of world-leading experts, in Rio de Janeiro, where the state of the art of this field was reviewed. Topics covered include the molecular analysis of bio-invasions, the recent developments in marine biotechnology, the factors affecting levels of genetic variation and population structure in marine organisms and their application to conservation biology, fisheries and aquaculture. This is the first book dedicated to the genetic study of marine organisms. It will be very useful to biology students, scientists and anyone working or simply interested in areas such as marine biology, zoology, ecology, and population and molecular genetics.
Download or read book The European Landing Obligation written by Sven Sebastian Uhlmann and published by Springer. This book was released on 2018-12-19 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book provides a comprehensive examination of the European Landing Obligation policy from many relevant perspectives. It includes evaluations of its impacts at economical, socio-cultural, ecological and institutional levels. It also discusses the feasibility and benefits of several potential mitigation strategies. The book was timely published, exactly at the time where the Landing Obligation was planned to be fully implemented. This book is of significant interest to all stakeholders involved, but also to the general public of Europe and to other jurisdictions throughout the world that are also searching for ways to deal with by-catch and discard issues.
Download or read book A Century of Maritime Science written by Jennifer Hubbard and published by University of Toronto Press. This book was released on 2016-01-01 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Century of Maritime Science reviews the fisheries, environmental, oceanographic, and aquaculture research conducted over the last hundred years at St. Andrews from the perspective of the participating scientists.
Download or read book Harp Seals Man and Ice written by David E. Sergeant and published by Fisheries and Oceans, Communications Directorate. This book was released on 1991 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reviews the biology and population dynamics of the harp seal, Phoca groenlandica Erxleben, the history of its hunting over several centuries and its eventual conservation.
Download or read book Evolution of Marine Coastal Ecosystems under the Pressure of Global Changes written by Hubert-Jean Ceccaldi and published by Springer Nature. This book was released on 2020-06-15 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coastal and estuarine environments at the interface of terrestrial and marine areas are among the most productive in the world. However, since the beginning of the industrial era, these ecosystems have been subjected to strong anthropogenic pressures intensified from the second half of the 20th century, when there was a marked acceleration in the warming (climate change) of the continents, particularly at high latitudes. Coastal ecosystems are highly vulnerable to alteration of their physical, chemical and biological characteristics (marine intrusion, acidification of marine environments, changes in ecosystems, evolution and artificialization of the coastline, etc.).In contact with heavily populated areas, these environments are often the receptacle of a lot of chemical and biological pollution sources that significantly diminish their resilience. In this context of accelerated evolution and degradation of these areas important for food security of many populations around the world, it is necessary to better identify the factors of pressure and understand, at different scales of observation, their effects and impacts on the biodiversity and on the socio-eco-systems, in order to determine the degree of vulnerability of these coastal ecosystems and the risks they face. A transdisciplinary and integrated approach is required to prevent risks. Within this framework, operational coastal oceanography occupies an important place but also the implementation of a true socio-eco-system approach in order to set up an environmentally friendly development.
