Download or read book Defining Genetic Population Structure and Historical Connectivity of Snow Crab Chionoecetes Opilio written by Gregory T. Albrecht and published by . This book was released on 2011 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: The snow crab (Chionoecetes opilio) is a valuable commercial resource within the Bering Sea, as well as other areas in the North Pacific and Atlantic Oceans. Large populations are known to exist within the Chukchi and Beaufort Seas, including recently discovered commercial sized individuals (Beaufort). However, genetic connectivity throughout these regions has not been examined until now. Based on seven polymorphic microsatellite loci, relatively low population genetic structuring occurs throughout the Alaskan region (Gst = 0.001). This homogeneity is likely due to long-distance larval dispersal, adult migrations, and a possible recent population expansion following the last glacial maximum. Furthermore, meta-population analysis was conducted for Alaskan and Northwest Atlantic stocks. Although significant genetic divergence characterizes the West Greenland stock in relation to all other populations, low divergence (Gst = 0.005) was found between Atlantic Canada crabs and those from the Alaska region. Larval dispersal between regions is highly unlikely due to the transit distance. Therefore, low divergence is likely the result of a recent population expansion into the Northwest Atlantic

Download or read book Defining Genetic Structure in Alaskan Populations of the Snow Crab Chionoecetes Opilio written by Sarah Mincks Hardy and published by . This book was released on 2011 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reproduction and Population Structure of the Snow Crab Chionoecetes Opilio in the Far Eastern Seas written by and published by . This book was released on 1995 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes the reproductive process in the snow crab, an important commercial species in the Far East. The authors conducted studies at the cellular, organic, organismic, and populational levels, taking into account the ecological factors of the crab's habitat. The authors subjected crabs of different size groups to histological analysis, studied the spawning process and the productivity of gametogenesis in crabs of different age groups, and studied the distribution of larvae, young, and adult crabs during expeditions to the Bering Sea, Sea of Okhotsk, and Sea of Japan. They also discuss the spatial distribution of the snow crab in the north Pacific and the factors that determine the boundaries of that distribution.

Download or read book Reproduction and Population Structure of the Snow Crab Chionoecetes Opilio in the Far Eastern Seas written by and published by . This book was released on 1988 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Population Structure Reproductive Status and Diet of Snow Crabs Chionoecetes Opilio in the Northern Bering Sea written by Jason M. Kolts and published by . This book was released on 2012 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the Bering Sea, snow crabs (Chionoecetes opilio) are both an important commercial shellfish and a dominant benthic predator. However, few data exist for snow crabs in the area between the troubled commercial fishery in the southeast Bering Sea and the Chukchi Sea. I collected extensive data on the abundance and distributions of snow crabs of varying life stages between St. Matthew Island and Bering Strait (60-66° N). I found that snow crabs were extremely abundant in that region despite bottom-water temperatures that cause negative energy balance for much or all of the year. This dissertation focuses on the following questions: (1) by what demographic mechanisms do very cold temperatures limit the local productivity of snow crabs, (2) what oceanographic and demographic mechanisms can sustain their populations in cold areas, (3) could populations in cold areas contribute to production of harvestable crabs at larger scales, (4) to what extent do diets of snow crabs of different sexes and sizes correlate to abundance and biomass of available prey over this large region, and (5) how effective are stomach content, fatty acid, and stable isotope analyses in indicating the diets of snow crabs in this area?

Download or read book Genetic Diversity and Population Genetic Structure of Tanner Crab Chionoecetes Bairdi in Alaskan Waters written by Genevieve M. Johnson and published by . This book was released on 2019 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tanner crab (Chionoecetes bairdi) is a large-bodied species of crab harvested in commercial, personal use, and subsistence fisheries across Alaska. The commercial fisheries were highly productive until the 1980s, when most stocks faced major declines and were closed to harvest. The recovery success of stocks throughout the state has been variable throughout the subsequent decades, leading managers to question whether there are aspects of the population dynamics that are not accounted for. There is limited information on the genetic population structure of C. bairdi in Alaskan waters, which has caused uncertainty about whether established management areas align well with distribution and migration patterns for this species. I applied novel high throughput sequencing methods to measure genetic diversity and investigate the genetic population structure of C. bairdi in Alaskan waters. Genomic DNA was isolated from samples collected from Southeast Alaska, Prince William Sound, and the Eastern Bering Sea, both east and west of 166°W longitude, and processed according to a Double-Digest Restriction-Associated DNA Sequencing protocol. The final genotype assembly included 89 individuals that were genotyped at 2,740 independent, neutral single-nucleotide polymorphism (SNP) sites, and contained 3.06% missing data. The average observed heterozygosity across SNP sites within regions was significantly lower than the average heterozygosity expected for populations in Hardy-Weinberg equilibrium. An analysis of molecular variance indicated that genetic variability was mostly found within individuals (90%), 10% of variability was observed between individuals within sampling regions, and no significant amount of variation was detected between sampling regions. Furthermore, pairwise FST estimates between sampling regions were low, and thus the null model of panmixia could not be rejected. Principal components analysis was also congruent with a model of no differentiation among regions. Bayesian analysis implemented in the program STRUCTURE did not support any population partitioning above K = 1 clusters, again indicating that there is not substantial genetic differentiation among the regions sampled from across the state of Alaska. These results indicate high gene flow throughout the distribution of Tanner crab across the Alaska continental shelf. Recognized stocks are genetically indistinguishable from each other. This may indicate that stocks exchange a substantial number of migrants, and may not operate independently. This new information can provide insights as management plans are evaluated and refined.

Download or read book Genetic Connectivity of Dungeness Crab Cancer Magister in the California Current System and Puget Sound written by Tyler M. Jackson and published by . This book was released on 2016 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding connectivity among exploited populations is critical to their sustainable management and long-term viability. In the marine environment, estimates of connectivity often rely on the use of genetic markers, as dispersal primarily occurs during a planktonic larval phase which is difficult to track using direct methods. In this thesis, we investigated the population genetic structure of the most valuable commercially harvested species on the west coast of the United States, the Dungeness crab (Cancer magister). We utilized both population- and individual-based genetic analyses to establish baseline knowledge of genetic connectivity of Dungeness crab throughout ~1,200 km of the California Current System (CCS) in 2012, and tested for inter-annual variability in our estimates by sampling again in 2014. In 2012, we observed a pattern of isolation by distance despite there being little genetic population structure throughout our study range. In addition, several sites had significant evidence of kin aggregation, which was correlated with genetic differentiation as measured by pairwise FST. In 2014, pairwise FST estimates were noticeably lower, there was no spatial autocorrelation, and fewer sights had significant evidence of kin aggregation. We attributed these findings to increased migrant exchange during potential larval dispersal years, which was mediated by variation in physical oceanographic conditions (i.e. Pacific Decadal Oscillation phase, timing of the spring transition, amount of upwelling during the spring and summer). Dispersal trajectory, and thus gene flow, is likely influenced by variation in physical oceanographic conditions, thereby affecting genetic population structure. Estimates of effective population size (N[subscript E]) indicated that N[subscript E] was large in both 2012 and 2014, but we were unable to discern any change between years. Together, these findings suggest that Dungeness crab in the CCS may constitute a single evolutionary population, though geographically limited dispersal results in isolation by distance. We also evaluated genetic connectivity among Dungeness crab inhabiting a partially enclosed water body, Puget Sound, in comparison to those residing in the coastal ocean. With the exception of Hood Canal, we observed genetic homogeneity within both Puget Sound and coastal Washington. Genetic differentiation between Puget Sound and coastal Washington was variable among sites, therefore genetic connectivity is stronger within either area than between them. Overall, our results suggest that Dungeness crab exemplify characteristics of a ‘high gene flow’ species, despite evidence supporting geographically limited gene flow. Our findings did not indicate that altering the management strategy to reflect discrete genetic subunits or conversation needs (i.e. low genetic diversity) is necessary at this time. In addition, our findings highlight the need for future research to investigate demographic processes that influence gene flow (i.e. dispersal trajectory).

Download or read book Proceedings of the North Pacific Symposium on Invertebrate Stock Assessment and Management written by National Research Council Canada and published by NRC Research Press. This book was released on 1998 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a symposium that focused on new, innovative evaluation of the implications and needs for changing management approaches and demands in invertebrate fishery science. Species covered in the presentations include crustaceans, gastropods, echinoderms, and bivalves. Presentations are organized in the following subject areas: assessment of abundance and related parameters; growth, mortality, and yield per recruit; spatial pattern and its implications; the fishing process; population dynamics; the fishery as a selective force; invertebrate fisheries management; and regional perspectives from the north Pacific. The proceedings conclude with a symposium overview.

Download or read book Oceanic Abstracts written by and published by . This book was released on 1995-05 with total page 814 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Canadian Journal of Fisheries and Aquatic Sciences written by and published by . This book was released on 2008 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Early Life History and Recruitment in Fish Populations written by R.C. Chambers and published by Springer Science & Business Media. This book was released on 1997-07-31 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many of the processes influencing recruitment to an adult fish population or entry into a fishery occur very early in life. The variations in life histories and behaviours of young fish and the selective processes operating on this variation ultimately determine the identities and abundance of survivors. This important volume brings together contributions from many of the world's leading researchers from the field of fish ecology. The book focuses on three major themes of pressing importance in the analysis of the role that the early life history of fishes plays in the number and quality of recruits: the selective processes at play in their early life history; the contributions of early life history to the understanding of recruitment.

Download or read book Sexual Biology and Reproduction in Crustaceans written by Thanumalaya Subramoniam and published by Academic Press. This book was released on 2016-09-27 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sexual Biology and Reproduction in Crustaceans covers crustacean reproduction as it deals with the structural morphology of the gamete-producing primary sex organs, such as the testis and ovary, the formation and maturation of gametes, their fusion during fertilization, and embryonic development that lead to the release of larvae. Constituting a diverse assemblage of animals, crustaceans are best known by their common representatives, such as shrimps, lobsters, and crabs, but also include many more less familiar, but biologically important forms. This work covers the variety of ways in which both male and female gametes are produced by evolving different sexual systems in crustaceans, the range of reproductive systems, and the accordingly, and highly diverse, mechanistic modes of sex determination. In addition, the book features such topics as genetic and environmental determinants in sex determination pattern, variability of mechanisms of fertilization among different species, the origin of different mating systems, the associated mating and brooding behaviors, and the adaptive ability to different environmental conditions with discussion on the evolutionary ecology of social and sexual systems in certain species, which have shown eusocial tendencies, similar to social insects. Marine species occupying diversified ecological niches in tropical and temperate zones reproduce under definitive environmental conditions. Therefore, reproductive ecology of different crustaceans inhabiting different ecological niches also constitutes another important aspect of the work, along with yolk utilization and embryogenesis leading to release of different larval forms, which reflect on their aquatic adaptability. - Forms a valuable source of recent references on the current research in crustacean reproductive physiology - Covers various mating and breeding systems, providing illustrative examples for sexual selection, parental care of developing eggs and embryos, and the evolution of other reproductive behaviors - Features contributions written in the form of review articles, enabling readers to not only gain information in the respective subject, but also help them stimulate ideas in their chosen field of research - Includes a glossary created by the author to define technical terms - Demonstrates the ability of crustacean species to serve as useful model systems for other organisms, to investigate issues related to sexual conflict, mate choice, and sperm competition - Discusses techniques in endocrine research to help researchers in aquaculture develop protocols in the control of reproduction

Download or read book In the Wrong Place Alien Marine Crustaceans Distribution Biology and Impacts written by Bella S. Galil and published by Springer Science & Business Media. This book was released on 2011-04-01 with total page 714 pages. Available in PDF, EPUB and Kindle. Book excerpt: In The Wrong Place: Alien Marine Crustaceans - Distribution, Biology And Impacts provides a unique view into the remarkable story of how shrimps, crabs, and lobsters – and their many relatives – have been distributed around the world by human activity, and the profound implications of this global reorganization of biodiversity for marine conservation biology. Many crustaceans form the base of marine food chains, and are often prominent predators and competitors acting as ecological engineers in marine ecosystems. Commencing in the 1800s global commerce began to move hundreds – perhaps thousands – of species of marine crustaceans across oceans and between continents, both intentionally and unintentionally. This book tells the story of these invasions from Arctic waters to tropical shores, highlighting not only the importance and impact of all prominent crustacean invasions in the world's oceans, but also the commercial exploitation of invasive crabs and shrimps. Topics explored for the first time in one volume include the historical roots of man's impact on crustacean biogeography, the global dispersal of crabs, barnacle invasions, insights into the potential scale of tropical invasions, the history of the world's most widely cultured shrimp, the invasive history and management of red king crabs in Norway, Chinese mitten crabs in England, and American blue crabs in Europe, the evolutionary ecology of green crabs, and many other subjects as well, touching upon all ocean shores.

Download or read book Fully protected Marine Reserves written by Callum M. Roberts and published by . This book was released on 2000 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biology of the Land Crabs written by Warren W. Burggren and published by Cambridge University Press. This book was released on 1988-04-29 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interest in land crabs has burgeoned as biologists have increasingly focused on the evolution of terrestriality. Before the publication of this volume in 1988, there had been no single comprehensive source of information to serve biologists interested in the diverse aspects of terrestrial decapod crustacean. Biology of the Land Crabs was the first synthesis of recent and long-established findings on brachyuran and anomuran crustaceans that have evolved varying degrees of adaptation for life on land. Chapters by leading researchers take a coordinated evolutionary and comparative approach to systematics and evolution, ecology, behaviour, reproduction, growth and molting, ion and water balance, respiration and circulation, and energetics and locomotion. Each discusses how terrestrial species have become adapted from ancestral freshwater or marine forms. With its extensive bibliography and comprehensive index, including the natural history of nearly eighty species of brachyuran and anomuran crabs, Biology of the Land Crabs will continue to be an invaluable reference for researchers and advanced students.

Download or read book Atlantic Cod written by George A. Rose and published by John Wiley & Sons. This book was released on 2019-02-26 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive handbook, covering all aspects of the Atlantic cod including the biology, ecology, life histories, behaviour, commercial exploitation and conservation Not only is Atlantic cod one of the most valuable food fish in the world’s oceans, it is an important component of North Atlantic ecosystems and has been subject to much research into its biology, ecology and exploitation. After hundreds of years of exploitation, overfishing in the last half of the 20th Century caused many stocks to collapse, most famously the Northern cod stock off Newfoundland and Labrador, Canada. Since then, most cod stocks have been better researched and managed, but remain in a variety of states, from fully recovered to continued decline. This book, written by world experts, describes that research and management, and the importance of cod and its fisheries on North Atlantic cultures and economies, with impacts well beyond the range of the species. Atlantic Cod: Bio-Ecology of the Fish offers insightful chapter coverage of cod nomenclature, taxonomy, phylogeny and morphology; physiology and ecophysiology; reproduction and spawning behavior; early life history and pre-recruitment processes; migrations, movements and stock identity; feeding, growth and energetics; the place of cod in the ecosystem; the exploitation of cod through history and present day commercial fisheries and precautionary management for sustainable fisheries; impacts of climate change on cod biology and ecology; and the future of the species and its fisheries. Discusses the major commercial importance of Atlantic cod through history Provides a comprehensive treatment of the bio-ecology of the most researched and highly exploited fully marine species Examines how the decline (and recovery) of cod stocks is of great political and scientific interest An essential purchase for marine fisheries scientists Atlantic Cod: Bio-Ecology of the Fish is a vital book for all fisheries scientists, managers and fish biologists.

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.