Improving Fish Stock Assessments

Improving Fish Stock Assessments PDF Author: National Research Council
Publisher: National Academies Press
ISBN: 0309174406
Category : Technology & Engineering
Languages : en
Pages : 194

Get Book Here

Book Description
Ocean harvests have plateaued worldwide and many important commercial stocks have been depleted. This has caused great concern among scientists, fishery managers, the fishing community, and the public. This book evaluates the major models used for estimating the size and structure of marine fish populations (stock assessments) and changes in populations over time. It demonstrates how problems that may occur in fisheries dataâ€"for example underreporting or changes in the likelihood that fish can be caught with a given type of gearâ€"can seriously degrade the quality of stock assessments. The volume makes recommendations for means to improve stock assessments and their use in fishery management.

Improving Fish Stock Assessments

Improving Fish Stock Assessments PDF Author: National Research Council
Publisher: National Academies Press
ISBN: 0309174406
Category : Technology & Engineering
Languages : en
Pages : 194

Get Book Here

Book Description
Ocean harvests have plateaued worldwide and many important commercial stocks have been depleted. This has caused great concern among scientists, fishery managers, the fishing community, and the public. This book evaluates the major models used for estimating the size and structure of marine fish populations (stock assessments) and changes in populations over time. It demonstrates how problems that may occur in fisheries dataâ€"for example underreporting or changes in the likelihood that fish can be caught with a given type of gearâ€"can seriously degrade the quality of stock assessments. The volume makes recommendations for means to improve stock assessments and their use in fishery management.

Risk Evaluation and Biological Reference Points for Fisheries Management

Risk Evaluation and Biological Reference Points for Fisheries Management PDF Author: National Research Council Canada
Publisher: NRC Research Press
ISBN: 9780660149561
Category : Nature
Languages : en
Pages : 456

Get Book Here

Book Description
Papers presented: 1) Reference points for fisheries management: the western Canadian experience; 2) Reference points for fisheries management: the eastern Canadian experience; 3) Reference points for fisheries management: the ICES experience; 4) Spawning stock biomass per recruit in fisheries management: foundation and current use; 5) The development of a management procedure for the South African anchovy resource; 6) How much spawning per recruit is enough?; 7) The behaviour of Flow, Fmed and Fhigh in response to variation in parameters used for their estimation; 8) The Barents Sea capelin stock collapse: a lesson to learn; 9) Variance estimates for fisheries assessment: their importance and how best to evaluate them; 10) Evaluating the accuracy of projected catch estimates from sequential population analysis and trawl survey abundance estimates; 11) Bootstrap estimates of ADAPT parameters, their projection in risk analysis and their retrospective patterns; 12) Analytical estimates of reliability for the projected yield from commercial fisheries; 13) Risk evaluation of the 10% harvest rate procedure for capelin in NAFO Division 3L; 14) Using jackknife and Monte Carlo simulation techniques to evaluate forecast models for Atlantic salmon; 15) Monte Carlo evaluation of risks for biological reference points used in New Zealand fishery assessments; 16) A comparison of event free risk analysis to Ricker spawner-recruit simulation: an example with Atlantic menhaden; 17) Choosing a management strategy for stock rebuilding when control is uncertain; 18) Risks and uncertainties in the management of a single-cohort squid fishery: the Falkland Islands Illex fishery as an example; 19) Risks of over- and under-fishing new resources; 20) Estimation of density-dependent natural mortality in British Columbia herring stocks through SSPA and its impact on sustainable harvesting strategies; 21) The comparative performance of production-model and ad hoc tuned VPA based feedback-control management procedures for the stock of Cape hake off the west coast of Africa; 22) A proposal for a threshold stock size and maximum fishing mortality rate; 23) Biological reference points for Canadian Atlantic gadoid stocks; 24) Stochastic locally-optimal harvesting; 25) ITQ based fisheries management; 26) Bioeconomic methods for determining TACs; 27) Management strategies: fixed or variable catch quotas; 28) Bioeconomic impacts of TAC adjustment strategies: a model applied to northern cod; 29) Experimental management programs for two rockfish stocks off British Columbia; 30)A brief overview of the experimental approach to reducing uncertainty in fisheries management; 31) Fisheries management organizations: a study of uncertainty.

Stock Assessment for Fishery Management

Stock Assessment for Fishery Management PDF Author: Daniel D. Hoggarth
Publisher: Food & Agriculture Org.
ISBN: 9789251055038
Category : Business & Economics
Languages : en
Pages : 284

Get Book Here

Book Description
This publication contains guidelines for fish stock assessment and fishery management using the software tools and other outputs developed by the UK Department for International Development's Fisheries Management Science Programme (FMSP) from 1992 to 2004. It includes a CD-ROM with the installation files for each of the four FMSP software tools: LFDA (Length Frequency Data Analysis), CEDA (Catch Effort Data Analysis), YIELD and ParFish (Participatory Fisheries Stock Assessment).

On the Dynamics of Exploited Fish Populations

On the Dynamics of Exploited Fish Populations PDF Author: Raymond J.H. Beverton
Publisher: Springer Science & Business Media
ISBN: 9401121060
Category : Science
Languages : en
Pages : 541

Get Book Here

Book Description
Among the fishes, a remarkably wide range of biological adaptations to diverse habitats has evolved. As well as living in the conventional habitats of lakes, ponds, rivers, rock pools and the open sea, fish have solved the problems of life in deserts, in the deep sea, in the cold antarctic, and in warm waters of high alkalinity or of low oxygen. Along with these adaptations, we find the most impressive specializations of morphology, physiology and behaviour. For example we can marvel at the high-speed swimming of the marlins, sailfish and warm-blooded tunas, air-breathing in catfish and lungfish, parental care in the mouth-brooding cichlids, and viviparity in many sharks and toothcarps. Moreover, fish are of considerable importance to the survival of the human species in the form of nutritious, delicious and diverse food. Rational exploitation and management of our global stocks of fishes must rely upon a detailed and precise insight of their biology. The Chapman & Hall Fish and Fisheries Series aims to present timely volumes reviewing important aspects of fish biology. Most volumes will be of interest to research workers in biology, zoology, ecology and physiology but an additional aim is for the books to be accessible to a wide spectrum of non-specialist readers ranging from undergraduates and postgraduates to those with an interest in industrial and commercial aspects of fish and fisheries.

The State of World Fisheries and Aquaculture 2020

The State of World Fisheries and Aquaculture 2020 PDF Author: FAO
Publisher: Food and Agriculture Organization of the United Nations
ISBN: 9251326924
Category : Technology & Engineering
Languages : en
Pages : 224

Get Book Here

Book Description
The 2020 edition of The State of World Fisheries and Aquaculture has a particular focus on sustainability. This reflects a number of specific considerations. First, 2020 marks the twenty-fifth anniversary of the Code of Conduct for Responsible Fisheries (the Code). Second, several Sustainable Development Goal indicators mature in 2020. Third, FAO hosted the International Symposium on Fisheries Sustainability in late 2019, and fourth, 2020 sees the finalization of specific FAO guidelines on sustainable aquaculture growth, and on social sustainability along value chains. While Part 1 retains the format of previous editions, the structure of the rest of the publication has been revised. Part 2 opens with a special section marking the twenty fifth anniversary of the Code. It also focuses on issues coming to the fore, in particular, those related to Sustainable Development Goal 14 and its indicators for which FAO is the “custodian” agency. In addition, Part 2 covers various aspects of fisheries and aquaculture sustainability. The topics discussed range widely, from data and information systems to ocean pollution, product legality, user rights and climate change adaptation. Part 3 now forms the final part of the publication, covering projections and emerging issues such as new technologies and aquaculture biosecurity. It concludes by outlining steps towards a new vision for capture fisheries. The State of World Fisheries and Aquaculture aims to provide objective, reliable and up-to-date information to a wide audience – policymakers, managers, scientists, stakeholders and indeed everyone interested in the fisheries and aquaculture sector.

Data preparation to inform assessment and management approaches in data-limited fisheries

Data preparation to inform assessment and management approaches in data-limited fisheries PDF Author: Amoroso, R.
Publisher: Food & Agriculture Org. [Author]
ISBN: 9251387095
Category : Technology & Engineering
Languages : en
Pages : 124

Get Book Here

Book Description
In fisheries science and management, it is not uncommon that fishery data are used at “face value”, as inputs into data-limited assessments or empirical indicator-based frameworks for management, without first conducting a thorough exploration and critical review of the data. [Author] This practice may lead to biases in results and misdirected fishery management actions. [Author] To address intermediate steps between data collection and any analysis used to inform stock status, this manual provides guidance on how to prepare, explore and critically review fishery data in data-limited situations. [Author] Throughout the manual, guidance and sample data are provided primarily in Microsoft Excel or in comma separated value (CSV) file formats, as well as through FishualizeR, a publicly available, web-based, R Shiny app that was developed to support the manual. [Author] Instructions in this manual are not intended to present a single, prescriptive path, but rather to provide guidance that may be further tailored to each individual context. [Author] It is the authors’ hope and intent that the guidance contained in this manual will allow users to better understand their data, make corrections, and gain a deeper understanding of the data’s utility in assessment and management of data-limited fisheries. [Author]

Quantitative Fisheries Stock Assessment

Quantitative Fisheries Stock Assessment PDF Author: R. Hilborn
Publisher: Springer Science & Business Media
ISBN: 1461535980
Category : Science
Languages : en
Pages : 575

Get Book Here

Book Description
This book really began in 1980 with our first microcomputer, an Apple II +. The great value of the Apple II + was that we could take the computer programs we had been building on mainframe and mini-computers, and make them available to the many fisheries biologists who also had Apple II + 's. About 6 months after we got our first Apple, John Glaister came through Vancouver and saw what we were doing and realized that his agency (New South Wales State Fisheries) had the same equipment and could run the same programs. John organized a training course in Australia where we showed about 25 Australian fisheries biologists how to use microcomputers to do many standard fisheries analyses. In the process of organizing this and sub sequent courses we developed a series of lecture notes. Over the last 10 years these notes have evolved into the chapters of this book.

Fish Population Dynamics, Monitoring, and Management

Fish Population Dynamics, Monitoring, and Management PDF Author: Ichiro Aoki
Publisher: Springer
ISBN: 443156621X
Category : Science
Languages : en
Pages : 248

Get Book Here

Book Description
This book explores how we can solve the urgent problem of optimizing the use of variable, uncertain but finite fisheries resources while maintaining sustainability from a marine-ecosystem conservation perspective. It offers readers a broad understanding of the current methods and theory for sustainable exploitation of fisheries resources, and introduces recent findings and technological developments. The book is divided into three parts: Part I discusses fish stock dynamics, and illustrates how ecological processes affecting life cycles and biological interactions in marine environments lead to fish stock variability in space and time in major fish groups; small pelagic fish, demersal fish and large predatory fish. These insights shed light on the mechanisms underlying the variability in fish stocks and form the essential biological basis for fisheries management. Part II addresses the technologies and systems that monitor changes in fisheries resources and marine ecosystems using two approaches: fishery-dependent and fishery-independent data. It also describes acoustic surveys and biological sampling, as well as stock assessment methods. Part III examines management models for effectively assessing the natural variability in fisheries resources. The authors explore ways of determining the allowable catch in response to changes in stock abundance and how to incorporate ecological processes and monitoring procedures into management models. This book offers readers a broad understanding of sustainable exploitation as well as insights into fisheries management for the next generation.

Virtual Population Analysis

Virtual Population Analysis PDF Author: Hans Lassen
Publisher: Food & Agriculture Org.
ISBN: 9789251045336
Category : Fish populations
Languages : en
Pages : 144

Get Book Here

Book Description
Virtual population analysis (VPA) is a widely used model for the analysis of fished populations. While there are many VPA techniques, they vary in the way they use data and fit the model rather than in the form of the model itself. This manual describes the common VPA model and the assumptions on which it is based, together with descriptions of associated diagnostic procedures and common reference points

Guidelines for the Routine Collection of Capture Fishery Data

Guidelines for the Routine Collection of Capture Fishery Data PDF Author: Food and Agriculture Organization of the United Nations
Publisher: Food & Agriculture Org.
ISBN: 9789251043042
Category : Electronic books
Languages : en
Pages : 128

Get Book Here

Book Description
"These guidelines aim to help those who design routine data collection programmes, focusing on the relationship between typical questions asked by policy-makers and managers, and the data required for providing reliable answers. Fisheries policy and management objectives, particularly under the precautionary approach, need to be based upon analyses of reliable data. Data are needed to make rational decisions, evaluate the fisheries performance in relation to management activities and fulfil regional requirements. These objectives are achieved using fishery performance indicators. Indicators are used to measure the state of the resource, the performance of fishing controls, economic efficiency, socio-economic performance and social continuity. The primary factor in choosing what data to collect is the link between the necessary operational, biological, economic and socio-cultural indicators and their associated variables. The way in which different data variables are collected needs tobe tailored to the structure of the fishery. The strategy will be strongly influenced by the budget and personnel available, and the degree to which fishers and others co-operate. The programme must identify which variables should be collected through complete enumeration and which can be sampled. Collection methods are influenced by the variable itself, the strategy, collection point and the skill of the enumerator. Once collected, fishery data must be stored securely, but made easily available for analysis, which is achieved through a computer-based data management system, following the basic data processing principles. The implementation of a data collection programme should follow a normal project cycle, developing a new legal and institutional framework as appropriate"--Abstract.