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MeetingMeeting documentReport of the IOTC CPUE Workshop 2013
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No results found.A Workshop developing assessing CPUE trends and techniques used by IOTC RFMO was held in AZTI Teclia in San Sebastian (Spain), from 21 to 22 October 2013. The following were the key issues and recommendations identified at the meeting: 1. Use of newer standardization techniques (GLMM, GEOSTATISTICAL APPROACHES and CORE AREA APPROACHES) using operatiol data to assess divergence in CPUE?s across fleets. 1.1. While standard approaches worked well in most cases, the CPUE WG recommended that newer ap proaches should be tested. The results of the workshop conducted over the two day period, indicated that the GLMM models tend to capture the trends better. In addition incorporating more vessel specifics and using geostatistical techniques is another approach to pursue over time. Filly, the use of core-area approaches may be informative for by-catch species. Moreover, the majority feeling of the group was that during CPUE standardization the use of operatiol data when they are available is recom mended as it will allow to capture the covariates that are important during the standardization process. 1.2. The strongest recommendation that came out of the workshop was that in areas where CPUE’s diverged the CPC’s were encouraged to meet inter-sessiolly to resolve the differences. In addition, the major CPC’s were encouraged to develop a combined CPUE from multiple fleets so it may capture the true abundance better. Approaches to possibly pursue are the following: i) Assess filtering approa ches on data and whether they have an effect, ii) examine spatial resolution on fleets operating and whether this is the primary reason for differences, and iii) examine fleet efficiencies by area, iv) use operatiol data for the standardization, and v) have a meeting amongst all operatiol level data across all fleets to assess an approach where we may look at catch rates across the broad areas. 1.3. Simulation studies could also be developed to assess which models work best (delta log-Normal, ze ro inflated versus standard GLM+constant, Tweedie). 1.4. Operatiol level data is useful if we want to quantify fishing fleet efficiency using fleet dymic covariates. More applications could be developed using the methods developed by Hoyle and Okamoto (2010), or Hoyle (2009), and prelimirily presented by Dr. Okamoto at the CPUE workshop. 1.5. Assess how core area Standardization works along with out of core or boundary area effects. 1.6. Environmental data would be useful to consider in relation to standardization approaches. However, the way it is usually performed in GLMs, where an environmental covariate is associated to each observation (in regular 1°, 5° or even 10° grids) , may not be the most pertinent as it does not allow to identify the ecological processes which may affect CPUE. Altertively, GLMs could be performed in sub-areas where the variability pattern of the environmental sigture is well identified (using spatial EOFs to delineate those sub-areas). In such sub-areas, GL Ms could be designed with and without environmental covariates to understand the potential effect of the environment. Environmental covariates should be in limited numbers (the lesser the better) and selected in order to test hypothesis on the ecological processes at stake. Develop robust CPUE series for other species and Working Parties. 2.1. The Working Group recommended to also focus the efforts in other species such as Temperate Tu. In addition the WG recommended, developing better CPUE data for Neritic Tu, and also improving the data and standardization on marlins and sharks. 2.2. Develop a reference manual for use in performing a CPUE standardization for any fleet in any working party (e.g. neritic tu WP or temperate tu WP). Criteria for inclusion of the data in a stock assessment should also be developed (possibly using ICCAT techniques as a baseline). With regard to Purse Seine data the following were recommended: 3.1. Approaches being pursued by EU scientist have some promise, and more work should be put in the development of an index of abundance for the PS fleet on Skipjack Tu, Yellowfin Tu and Bigeye Tu. 3.2. The availability of Vessel Monitoring System (VMS) data is a major requirement for the purse seine fishing fleet as it ebles to spatialize the nomil effort (i.e. fishing or searching time), which is key to appreciate the temporal changes in the spatial extent of the prospected areas. VMS data may also be used to alyze PS trajectories with the aim to discrimit e sets on FADs equipped with buoys from free school sets, log sets and foreign FADs sets (see after) 3.3. Purse seiners currently fish during the same trip on a combition of free-swimming and drifting FAD-associated schools. In addition, fishing on FADs results from both the detection of vessel-owned FADs through GPS geolocation systems as well as from the finding of 'foreign' FADs through bird detection for instance. Future alyses should focus on the separation of fishing time between searching and running towards FADs. Classification methods based on indicators describing spatial behaviour of vessels could eble to define typical fishing strategies and categorize trip components into such categories. 3.4. Data available on FAD activities collection have improved recently. Future alyses should focus on the definition of a fishing effort for purse seiners using FADs by (i) looking at the influence of the number of FADs owned by a vessel on individual CPUEs, (ii) by investigating the CPU Es in areas characterized by strong contrasts in FAD density. The influence of supply vessels on catch rates (e.g. the number of sets per day) and on the overall fishing capacity of the PS fleet should also be investigated at the vessel level through the information available from supply logbooks. 3.5. Alyses of temporal changes in individual and overall fleet catchability from CPUEs should be conducted to estimate fishing power creep and investigate how such changes are related with some major technological changes known for the PS fleet (e.g. bird radar). Including vessel effects into GLMs can reveal useful insights on vessel efficiency for such alyses. Attention should be paid also for change over time of fishery indicators which are part of the CPUE (e.g., number of set by day, % of successful set, catch size of the set). 4. The CPUE Workshop participants recommended that a thorough alysis of the history of the fishery would be useful for references for each species. In addition, t he Group agreed that a central body (the Secretariat) should undertake additiol activities in key areas (Neritic tus where they can develop/collate the existing data on catch and effort and alyse this for some key species (eg. Longtail and Kawakawa)). 5. The CPUE Standardization Working Group agreed that a reference document that IOTC could use in what criteria should be used in utilizing a dataset for CPUE Standardization for all WP would incorporate the specifics of the temporal and spatial co verage of the data, and useful covariates that could quantify the fishing activity and the environment in which the fish lived. -
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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. -
BookletHigh-profileFAO Strategy on Climate Change 2022–2031 2022The FAO Strategy on Climate Change 2022–2031 was endorsed by FAO Council in June 2022. This new strategy replaces the previous strategy from 2017 to better FAO's climate action with the Strategic Framework 2022-2031, and other FAO strategies that have been developed since then. The Strategy was elaborated following an inclusive process of consultation with FAO Members, FAO staff from headquarters and decentralized offices, as well as external partners. It articulates FAO's vision for agrifood systems by 2050, around three main pillars of action: at global and regional level, at country level, and at local level. The Strategy also encourages key guiding principles for action, such as science and innovation, inclusiveness, partnerships, and access to finance.
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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.