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MeetingMeeting documentStock assessment of bigeye tuna (Thunnus obesus) in the Indian Ocean based on a tuned VPA analysis 2013
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DocumentOther documentInvestigating the influence of length-frequency data on the stock assessment of Indian Ocean bigeye tuna 2013
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No results found.Most integrated stock assessment models are fit to altertive sources of data like indices of abundance and length/age composition of catches in specific fisheries. While indices of abundance are often standardized over time, not much attention is paid to the temporal stability of the length/age data. A sequential approach to fitting model outputs to all sources of data, varying the weight given to the length composition data, for Indian Ocean bigeye tu (Thunnus obesus) is examined in this paper. The sensitivity of the bigeye tu stock assessment to assumptions regarding the size-selectivity of key fisheries and the relative weight of size frequency data in the stock assessment is examined. Logistic, double normal, and cubic spline selectivity functions are used to model the size composition of catches in the main industrial fisheries (longline and purse seine). Overall, there is a poor fit of stock assessment models to the individual length frequency observations collected from these fi sheries, although margil improvements of fit were made when temporally variable selectivity was implemented in the SS-III framework using the above described functions. The most influential factor in the assessment was the weighting of the length composition data relative to the indices of stock abundance. Contradictory sigls between these two data sources have a large effect on spawning biomass dymics, and inference based on these weightings can produce different magement conclusions. We examin ed altertive hypotheses and discuss the merits of fitting to all sources of data, or discounting some information if it has been unreliably collected over time. We emphasize that understanding the data is key to performing a well-calibrated stock assessment, and further refinements to the approach pursued here are discussed. -
MeetingMeeting documentStock and risk assessments on bigeye tuna (Thunnus obesus) in the Indian Ocean based on AD Model Builder implemented Age-Structured Production Model (ASPM) 2013
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BookletCorporate general interestEmissions due to agriculture
Global, regional and country trends 2000–2018
2021Also available in:
No results found.The FAOSTAT emissions database is composed of several data domains covering the categories of the IPCC Agriculture, Forestry and Other Land Use (AFOLU) sector of the national GHG inventory. Energy use in agriculture is additionally included as relevant to emissions from agriculture as an economic production sector under the ISIC A statistical classification, though recognizing that, in terms of IPCC, they are instead part of the Energy sector of the national GHG inventory. FAO emissions estimates are available over the period 1961–2018 for agriculture production processes from crop and livestock activities. Land use emissions and removals are generally available only for the period 1990–2019. This analytical brief focuses on overall trends over the period 2000–2018. -
Book (series)FlagshipThe State of Food Security and Nutrition in the World 2021
Transforming food systems for food security, improved nutrition and affordable healthy diets for all
2021In recent years, several major drivers have put the world off track to ending world hunger and malnutrition in all its forms by 2030. The challenges have grown with the COVID-19 pandemic and related containment measures. This report presents the first global assessment of food insecurity and malnutrition for 2020 and offers some indication of what hunger might look like by 2030 in a scenario further complicated by the enduring effects of the COVID-19 pandemic. It also includes new estimates of the cost and affordability of healthy diets, which provide an important link between the food security and nutrition indicators and the analysis of their trends. Altogether, the report highlights the need for a deeper reflection on how to better address the global food security and nutrition situation.To understand how hunger and malnutrition have reached these critical levels, this report draws on the analyses of the past four editions, which have produced a vast, evidence-based body of knowledge of the major drivers behind the recent changes in food security and nutrition. These drivers, which are increasing in frequency and intensity, include conflicts, climate variability and extremes, and economic slowdowns and downturns – all exacerbated by the underlying causes of poverty and very high and persistent levels of inequality. In addition, millions of people around the world suffer from food insecurity and different forms of malnutrition because they cannot afford the cost of healthy diets. From a synthesized understanding of this knowledge, updates and additional analyses are generated to create a holistic view of the combined effects of these drivers, both on each other and on food systems, and how they negatively affect food security and nutrition around the world.In turn, the evidence informs an in-depth look at how to move from silo solutions to integrated food systems solutions. In this regard, the report proposes transformative pathways that specifically address the challenges posed by the major drivers, also highlighting the types of policy and investment portfolios required to transform food systems for food security, improved nutrition, and affordable healthy diets for all. The report observes that, while the pandemic has caused major setbacks, there is much to be learned from the vulnerabilities and inequalities it has laid bare. If taken to heart, these new insights and wisdom can help get the world back on track towards the goal of ending hunger, food insecurity, and malnutrition in all its forms. -
Book (series)Technical reportReport of the Africa Regional Consultative Meeting on Securing sustainable small-scale fisheries: bringing together responsible fisheries and social development, Maputo, Mozambique, 12-14 October 2010. / Rapport de l’atelier consultatif régional africain sur les pêches artisanales pour une pêche artisanale durable: associer la pêche responsable au développement social, Maputo, Mozambique, 12-14 octobre 2010. 2011
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No results found.The African workshop was one of three regional consultative workshops carried out as a follow-up to the 2009 inception workshop of the FAO Extra-Budgetary Programme on Fisheries and Aquaculture for Poverty Alleviation and Food Security. The workshops built on the outcomes of the Global Conference on Small-Scale Fisheries held in Bangkok in October 2008 and referred to the recommendations made by the 26th Session of the FAO Committee on Fisheries (COFI) in March 2009 with regard to the potential development of an international instrument and programme for small-scale fisheries. The purpose of the workshops was to provide guidance on the scope and contents of such an international small-scale fisheries instrument and on the possible priorities and implementation modalities for a global assistance programme. It was organised around plenary presentations on key subjects and working group discussions. The workshop agreed that an international instrument on small-scale fisheries and a rela ted programme would be important tools for securing sustainable small-scale fisheries. It recommended that a small-scale fisheries international instrument and assistance programme should be informed by human rights principles and existing instruments relevant to good governance and sustainable development, comprise the ecosystem approach to fisheries (EAF) as a guiding principle for resource management and development and incorporate Disaster Risk Management (DRM) and Climate Change Adaption (C CA) as an integral part considering that DRM is a continuum process, before, during and after a disaster. The workshop recognised the value and worldwide acceptance of the Code of Conduct for Responsible Fisheries and strongly felt that a small-scale fisheries instrument should be closely aligned to the Code. The instrument should build on what already exists and use a similar language to the Code. In developing the instrument, reference should be made not only to States but also to other sta keholders, recognizing the shared responsibility with regard to resource sustainability and livelihood security. Local, national and regional ownership should be ensured. Implementation aspects should be considered already at the design stage, including the need for technical guidance and supportive mechanisms. Results monitoring should be based on well-defined impact indicators and be an integral part of the implementation modalities.